MPA Literature Summaries

Addessi, L. 1994. Human disturbance and long-term changes on a rocky intertidal community. Ecological Applications. 4:768-797.

Abstract:

The effects of human recreational activities on a rocky intertidal habitat on the coast of San Diego, California, USA were investigated. Organisms susceptible to collection for food, bait, or aquaria were identified and served as key species for the study of biota disturbance. This study examined three major aspects: (1) Distribution and activities of people along the shoreline were documented. (2) Distribution and density of echinoderms and molluscs inhabiting the cryptic underrock surface were sampled along an identified gradient of disturbance. (3) Densities of conspicuous organisms inhabiting the underrock surface at the most disturbed location detected in the spring of 1971 were compared with those detected in the spring of 1991.

Surveys of human activity made during weekends with low tides exposing most of the intertidal zone (below 0 MLLW) during the daylight hours between December 1990 and August 1991 showed a definite pattern. People concentrated in an area with a 200 m radius centered on the primary accesses; areas farther from these points were less visited. The study site stood along a gradient of human disturbance, and the sampling of organisms along this indicated a gradient of biota disturbance as well. The density of all species was reduced in the more heavily visited intertidal area. The underrock community at the most heavily visited location changed substantially from spring 1971 to spring 1991. The density of most of the macroorganisms decreased between the two dates, with the exception of the density of small gastropods, which increased.

Even if more long-term studies are needed for determining the actual status of communities under the influence of human disturbance, the combination of spatial and longterm studies shows the importance of setting better policy and establishing more effective reserves in order to enhance and maintain species diversity and density.

Community structure; human disturbance; reserves; rocky intertidal.

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Airamé, S., J.E. Dugan, K.D. Lafferty, H. Leslie, D.A. McArdle, and R.R. Warner. 2003. Applying Ecological Criteria to Marine Reserve Design: A Case Study from the California Channel Islands. Ecological Applications 13(1) Supplement: S170-S184.

Abstract:

Using ecological criteria as a theoretical framework, we describe the steps involved in designing a network of marine reserves for conservation and fisheries management. Although we describe the case study of the Channel Islands, the approach to marine reserve design may be effective in other regions where traditional management alone does not sustain marine resources. A group of agencies, organizations, and individuals established clear goals for marine reserves in the Channel Islands, including conservation of ecosystem biodiversity, sustainable fisheries, economic viability, natural and cultural heritage, and education. Given the constraints of risk management, experimental design, monitoring, and enforcement, scientists recommended at least one, but no more than four, reserves in each biogeographic region. In general, the percentage of an area to be included in a reserve network depends on the goals. In the Channel Islands, after consideration of both conservation goals and the risk from human threats and natural catastrophes, scientists recommended reserving an area of 30-50% of all representative habitats in each biogeographic region. For most species of concern, except pinnipeds and seabirds, information about distributions, dispersal, and population growth was limited. As an alternative to species distribution information, suitable habitats for species of concern were used to locate potential reserve sites. We used a simulated annealing algorithm to identify potential reserve network scenarios that would represent all habitats within the smallest area possible. The analysis produced an array of potential reserve network scenarios that all met the established goals.

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Agardy, T., P. Bridgewater, M.P. Crosby, J. Day, P.K. Dayton, R. Kenchington, D. Laffoley, P. McConney, P.A. Murray, J.E. Parks, and L. Peau. 2003. Dangerous targets? Unresolved issues and ideological clashes around marine protected areas. Aquatic Conserv: Mar. Freshw. Ecosyst.

Abstract:

1. While conservationists, resource managers, scientists and coastal planners have recognized the broad applicability of marine protected areas (MPAs), they are often implemented without a firm understanding of the conservation science } both ecological and socio-economic } underlying marine protection. The rush to implement MPAs has set the stage for paradoxical differences of opinions in the marine conservation community.
2. The enthusiastic prescription of simplistic solutions to marine conservation problems risks polarization of interests and ultimately threatens bona fide progress in marine conservation. The blanket assignment and advocacy of empirically unsubstantiated rules of thumb in marine protection creates potentially dangerous targets for conservation science.
3. Clarity of definition, systematic testing of assumptions, and adaptive application of diverse MPA management approaches are needed so that the appropriate mix of various management tools can be utilized, depending upon specific goals and conditions. Scientists have a professional and ethical duty to map out those paths that are most likely to lead to improved resource management and understanding of the natural world, including the human element, whether or not they are convenient, politically correct or publicly magnetic.
4. The use of MPAs as a vehicle for promoting long-term conservation and sustainable use of marine biodiversity is in need of focus, and both philosophical and applied tune ups. A new paradigm arising out of integrated, multi-disciplinary science, management and education/outreach efforts must be adopted to help promote flexible, diverse and effective MPA management strategies. Given scientific uncertainties, MPAs should be designed so one can learn from their application and adjust their management strategies as needed, in the true spirit of adaptive management.
5. It is critical for the conservation community to examine why honest differences of opinion regarding MPAs have emerged, and recognize that inflexible attitudes and positions are potentially dangerous. We therefore discuss several questions } heretofore taken as implicit assumptions: (a) what are MPAs, (b) what purpose do MPAs serve, (c) are no-take MPAs the only legitimate MPAs, (d) should a single closed area target be set for all MPAs, and (e) how should policymakers and conservation communities deal with scientific uncertainty?

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Allison, G.W., S.D. Gaines, J. Lubencho, and H.P. Possingham. 2003. Ensuring Persistence of Marine Reserves: Catastrophes Require Adopting an Insurance Factor. Ecological Applications 13(1) Supplement: S8-S24.

Abstract:

When viewed across long temporal and large spatial scales, severe disturbances in marine ecosystems are not uncommon. Events such as hurricanes, oil spills, disease outbreaks, hypoxic events, harmful algal blooms, and coral bleaching can cause massive mortality and dramatic habitat effects on local or even regional scales. Although designers of marine reserves might assume low risk from such events over the short term, catastrophes are quite probable over the long term and must be considered for successful implementation of reserves. A simple way to increase performance of a reserve network is to incorporate into the reserve design a mechanism for calculating how much additional area would be required to buffer the reserve against effects of catastrophes. In this paper, we develop a method to determine this ''insurance factor'': a multiplier to calculate the additional reserve area necessary to ensure that functional goals of reserves will be met within a given ''catastrophe regime.'' We document and analyze the characteristics of two relatively well-studied types of disturbances: oil spills and hurricanes.We examine historical data to characterize catastrophe regimes within which reserves must function and use these regimes to illustrate the application of the insurance factor. This tool can be applied to any reserve design for which goals are defined by a quantifiable measure, such as a fraction of shoreline, that is necessary to accomplish a particular function. In the absence of such quantitative measures, the concept of additional area as insurance against catastrophes may still be useful.

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Allison, G. W., J. Lubchenco and M. H. Carr. 1998. Marine Reserves are Necessary but not Sufficient for Marine Conservation. Ecological Applications. 8:S79-S92.

The intensity of human pressure on marine systems has led to a push for stronger marine conservation efforts. Recently, marine reserves have become one highly advocated form of marine conservation, and the number of newly designated reserves has increased dramatically. Reserves will be essential for conservation efforts because they can provide unique protection for critical areas, they can provide a spatial escape for intensely exploited species, and they can potentially act as buffers against some management miscalculations and unforeseen or unusual conditions. Reserve design and effectiveness can be dramatically improved by better use of existing scientific understanding. Reserves are insufficient protection alone, however, because they are not isolated from all critical impacts. Communities residing within marine reserves are strongly influenced by the highly variable conditions of the water masses that continuously flow through them. To a much greater degree than in terrestrial systems, the scales of fundamental processes, such as population replenishment, are often much larger than reserves can encompass. Further, they offer no protection from some important threats, such as contamination by chemicals. Therefore, without adequate protection of species and ecosystems outside reserves, effectiveness of reserves will be severely compromised. We outline conditions under which reserves are likely to be effective, provide some guidelines for increasing their conservation potential, and suggest some research priorities to fill critical information gaps. We strongly support vastly increasing the number and size of marine reserves; at the same time, strong conservation efforts outside reserves must complement this effort. To date, most reserve design and site selection have involved little scientific justification. They must begin to do so to increase the likelihood of attaining conservation objectives.

Biodiversity; harvest refugia; marine parks; marine protected areas; open populations; population replenishment; Reserve design.

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Apostolaki, P., E.J. Milner-Gulland, M.K. McAllister, and G.P. Kirkwood. 2002. Modelling the effects of establishing a marine reserve for mobile fish species. Canadian Journal of Fisheries and Aquatic Sciences. 59: 405-415

Abstract:

We present a model of the effects of a marine reserve on spawning stock biomass (SSB) and short- and long-term yield for a size-structured species that exhibits seasonal movements. The model considers the effects of protecting nursery and (or) spawning grounds under a range of fishing mortalities and fish mobility rates. We consider two extremes of effort redistribution following reserve establishment and analyze the effects of a reserve when the fishery targets either mature or immature fish. We apply the model to the Mediterranean hake (Merluccius merluccius) and show that a marine reserve could be highly beneficial for this species. We demonstrate benefits from reserves not just for overexploited stocks of low-mobility species, but also (to a lesser extent) for underexploited stocks and high mobility species. Greatly increased resilience to overfishing is also found in the majority of cases. We show that a reserve provides benefits additional to those obtained from simple effort control. Benefits from reserves depend to a major extent on the amount of effort redistribution following reserve establishment and on fishing selectivity; hence, these factors should be key components of any evaluation of reserve effectiveness.

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Armstrong, C. W. and A. Skonhoft. 2006. Marine reserves: A bio-economic model with asymmetric density dependent migration. Ecological Economics. 57:466-476.

Abstract:

A static bioeconomic model of a marine reserve allowing asymmetric density  ependent migration between the reserve and the fishable area is introduced. This opens for habitat or ecosystem differences allowing different fish densities within and outside a reserve, not described in earlier studies. Four management scenarios are studied; (a) maximum harvest, (b) maximum current profit, (c) open access and (d) maximum sustainable yield (MSY) in the reserve. These are all analysed within the Induced Sustainable Yield Function (ISYF), giving the relationship between the fish abundance inside the reserve and the harvesting taking place outside. A numerical analysis shows that management focused on ensuring MSY within the reserve under the assumption of symmetric migration may be negative from an economic point of view, when the area outside the reserve is detrimental compared to the reserve. Furthermore, choice of management option may also have negative consequences for long run resource use if it is incorrectly assumed that density dependent migration is symmetric. The analysis also shows that the optimal area to close, either a more or a less attractive ecosystem for the resource in question, may differ depending on the management goal.

Bioeconomics; Marine reserves; Migration; Management.

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Babcock, R. C., E. K. Pikitch, M. K. McAllister, P. Apostolaki and C. Santora. 2005. A perspective on the use of spatialized indicators for ecosystem-based fishery management through spatial zoning. ICES Journal of Marine Science. 62:469-476.

Abstract:

Although much work has been done developing system-level indicators for ecosystembased fishery management (EBFM), few of those proposed include a spatial component. Even in single-species management, time and area closures have been applied without a clear understanding of what their effect might be on identifying overfishing thresholds and other reference points. For EBFM, spatial zoning of the marine environment, including no take marine reserves and areas where destructive fishing gears are prohibited, may become a prime management tool. Therefore, indicators of the effectiveness of spatial management will be required, along with an understanding of how indicators related to other objectives will be influenced. We review single-species models that have been used to model spatial zoning, including potential bias in assessment and current work on effort reallocation after area closure, as well as available ecosystem-based models and metrics and how they might account for spatial management. Metrics that can be derived from explicitly spatial approaches such as GIS-based ecosystem and fishery evaluations are also discussed.

CPUE; ecosystems; fishery management; GIS; spatial modelling.

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Babcock, R. C., S. Kelly, N. T. Shears, J. W. Walker and T. J. Willis. 1999. Changes in community structure in temperate marine reserves. Marine Ecology Progress Series. 189:125-134.

Abstract:

No-take' marine reserves provide a valuable tool for managing marine resources as well as for providing relatively undisturbed habitat with which to assess modifications to ecosystems. We studied 2 marine reserves in northeastern New Zealand, the Leigh Marine Reserve (established 1975) and Tawharanui Marine Park (established 1982) in order to assess whether changes in protected predator populations had resulted in other indirect changes to grazers and consequently to algal abundance. Estimates of abundance of the most common demersal predatory fish Pagrus auratus indicated that adults of this species (i.e. large enough to prey upon urchins) were at least 5.75 and 8.70 times more abundant inside reserves than in adjacent unprotected areas. Overall, P auratus were also much larger inside reserves with mean total lengths of 316 mm compared with 186 mm in fished areas. The spiny lobster Jasus edwardsii displayed similar trends, and was approximately 1.6 to 3.7 times more abundant inside the reserves than outside. Lobsters within the reserves had a mean carapace length of 109.9 mm, compared with 93.5 mm outside the reserves. In one of the reserves, densities of the sea urchin Evechinus chloroticus had declined from 4.9 to 1.4 m-2 since 1978 in areas formerly dominated by it. Consequently, kelp forests were more extensive in 1998 than they were at the time of reserve creation. Urchin-dominated barrens occupied only 14 % of available reef substratum in reserves as opposed to 40"4 in unprotected areas. These changes in community structure, which have persisted since at least 1994, demonstrate not only higher trophic complexity than anticipated in Australasian ecosystems but also increased primary and secondary productivity in marine reserves as a consequence of protection. Trends inside reserves indicate large-scale reduction of benthic primary production as an indirect result of fishing activity in unprotected areas.

Marine reserves; Habitat change; Trophic structure - Fishing effects; Urchins; Kelp; Fish; Spiny lobsters.

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Barrett, N. S., G. J. Edgar, C. D. Buxton and M. Haddon. 2007. Changes in fish assemblages following 10 years of protection in Tasmanian marine protected areas. Journal of Experimental Marine Biology and Ecology. 345:141-157.

Abstract:

Most studies examining effects of marine protected areas (MPAs) on fish assemblages are potentially confounded, either because they are once off comparisons between fished and unfished locations, or because they are snapshot studies over a fixed period. Here we compare long-term changes within fully protected Tasmanian marine reserves with changes at external reference sites on an annual basis over the first ten years of protection. The results highlight the importance of long-term datasets for differentiating changes occurring over differing time scales. Notable results include a statistically significant increase in abundance of Latridopsis forsteri and large fish (N300 mm) when examined across all reserves relative to controls, and a 10-fold increase in the abundance of large fish and a doubling of per site species richness of large fish within the Tinderbox Marine Reserve relative to controls. Short-term resident species that recruit sporadically show very different patterns in reserves compared to those that recruit regularly and have long-term age-class storage. While several recent reviews have suggested size of MPAs and duration of protection has little influence on the extent of recovery, our results suggest this is not the case and that responses can be slow, complex and species-specific. The extent of localised fishing pressure appeared to have a substantial influence on the degree of change detected, potentially confounding meta-analyses of recovery rates in MPAs if overlooked as a relevant parameter.

Effects of fishing; Long-term analysis; Marine reserve; Reserve size.

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Baskett, M. L., F. Micheli and S. A. Levin. 2007. Designing marine reserves for interacting species: Insights from theory. Biological Conservation. 137:163-179.

Abstract:

The primary goals of marine reserves include protecting biodiversity and ecosystem structure. Therefore, a multispecies approach to designing and monitoring reserve networks is necessary. To gain insight into how the interactions between species in marine communities may affect reserve design, we synthesize marine reserve community models and community models with habitat destruction and fragmentation, and we develop new extensions of existing models. This synthesis highlights the potential for species interactions to alter reserve design criteria; in particular, accounting for species interactions often leads to an increase in reserve size necessary to protect populations. Accounting for species interactions also indicates the need to base reserve design and monitoring on a variety of species, especially long-distance dispersers, inferior colonizers, and specialists. Finally, the new model extensions highlight how, given dispersal, source populations outside reserves as well as increases in fished populations after reserve establishment may negatively affect reserve populations of competitors or prey. Therefore, multispecies harvest dynamics outside reserves and before reserve establishment are critical to determining the appropriate reserve size, spacing, and expectations after establishment. These models highlight the importance of species interactions to reserve design and provide guidelines for how this complexity can begin to be incorporated into conservation planning.

Marine protected areas; Habitat loss; Predation; Competition; Mutualism; Community models.

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Becker, B. J., L. A. Levin, F. J. Fodrie and P. A. McMillan. 2007. Complex larval connectivity patterns among marine invertebrate populations. Proceedings of the National Academy of Sciences. 104:3267-3272.

Abstract:

Based on the belief that marine larvae, which can spend days to months in the planktonic stage, could be transported considerable distances by ocean currents, it has long been assumed that populations of coastal species with a planktonic larval stage are demographically open and highly ‘‘connected.’’ Such assumptions about the connectivity of coastal populations govern approaches to managing marine resources and shape our fundamental understanding of population dynamics and evolution, yet are rarely tested directly due to the small size and high mortality of marine larvae in a physically complex environment. Here, we document a successful application of elemental fingerprinting as a tracking tool to determine sources of settled invertebrates and show that coastal mussel larvae, previously thought to be highly dispersed, can be retained within 20–30 km of their natal origin. We compare two closely related and co-occurring species, Mytilus californianus and Mytilus galloprovincialis, and determine that, despite expected similarities, they exhibit substantially different connectivity patterns. Our use of an in situ larval culturing technique overcomes the previous challenge of applying microchemical tracking methods to species with completely planktonic development. The exchange of larvae and resulting connectivities among marine populations have fundamental consequences for the evolution and ecology of species and for the management of coastal resources.

Elemental fingerprinting; in situ larval culturing; larval retention; larval transport; Mytilus.

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Bell, J. 1983. Effects of depth and marine reserve fishing restrictions on the structure of a rocky reef fish assemblage in the North-Western Mediterranean Sea. The Journal of Applied Ecology. 20:357-369.

Abstract:

1. A visual scuba diving census, in which abundance and size class structure of conspicuous fish species were determined, was used to assess the effects of depth and marine reserve fishing restrictions on the structure of a Mediterranean rocky reef fish assemblage by comparing communities at sites from two depth ranges inside and outside a marine reserve.
2. The total assemblage had thirty-five conspicuous species and was dominated by Labridae (thirteen spp.) and Sparidae (nine spp.).
3. Mean species richness (number of species) and diversity (Shannon) did not differ significantly between sites.
4. Ordination of abundance data showed that occurrence and relative abundance of species was affected by depth (deep samples separated completely from shallow samples) and marine reserve status (samples from the marine reserve were significantly separated from those taken at the same depth outside the reserve).
5. Samples from the same depth were similar, because the majority of species showed a preference for either deep or shallow areas. The known biology of several species indicated that feeding requirements may be responsible for depth preferences.
6. Samples from reserve sites had signficantly higher densities of fish species sought after and/or vulnerable to local fishing methods, than those from non-reserve sites of similar depth.
7. Size frequency distributions of vulnerable species at reserve sites generally had a larger modal size class than distributions from non-reserve sites.
8. The data suggest that reduced fishing pressure in the reserve has provided effective protection for species vulnerable to fishing.

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Bellquist, L. F., C. G. Lowe and J. E. Caselle. 2008. Fine-scale movement patterns, site fidelity, and habitat selection of ocean whitefish (Caulolatilus princeps). Fisheries Research. 91:325-335.

The fishery for California groundfishes is managed using broad species complexes, although some non-groundfish species are managed similarly due to the perception of shared behavioral characteristics. This study integrates acoustic telemetry and a GIS to quantify movement patterns of one such species, the ocean whitefish (Caulolatilus princeps) in a marine protected area. Seventeen ocean whitefish were tagged and actively tracked over multiple 24-h periods to measure fine-scale movement patterns. Home ranges based on 95% kernel utilization distributions averaged 20,439±28,492 (±S.D.)m2. Fish were active during the day, foraging over sand habitat at depths averaging 21±8m, but were inactive at night, taking refuge near rocky reefs at depths averaging 15±7m. Seventeen additional fish were tagged with coded acoustic transmitters and passively tracked using automated underwater acoustic receivers for up to 1 year. Approximately 75% of these fish exhibited long-term (1 year) fidelity to home ranges in the study area. Results suggest that MPAs can be an effective means of protecting populations of ocean whitefish and based on their habitat associations, ocean whitefish can be managed separately from other reef associated groundfishes.

Movement patterns; Home range; Site fidelity; Habitat selection; Marine protected area; Acoustic telemetry; Ocean whitefish.

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Benedetti-Cecchi, L., F. Pannacciulli, F. Bulleri, P. S. Moschella, L. Airoldi, G. Relini and F. Cinelli. 2001. Predicting the consequences of anthropogenic disturbance: large-scale effects of loss of canopy algae on rocky shores. Marine Ecology Progress Series. 214:137-150.

Anthropogenic disturbances affect natural populations and assemblages by interacting with fundamental ecological processes. Field experiments simulating the effects of human activities at the appropriate spatial and temporal scales are useful to understand these interactions and eventually to predict their ecological consequences. In the Mediterranean, low-shore habitats of rocky coasts are often dominated by canopy algae Cystoseira spp., but these species are frequently replaced by assemblages of turf-forming algae and mussel beds. We propose that anthropogenic disturbance is the proximate cause of loss of Cystoseira in the Mediterranean, and that the disappearance of canopy algae causes an increase in cover of turf-forming species in disturbed habitats. Two hypotheses were investigated to test this proposition: (1) canopy algae will be dominant in relatively pristine habitats while turf-forming algae will be more abundant in urban areas, and (2) removal of canopy algae in unpolluted areas will result in the development of assemblages similar to those found in urban areas. We tested the first hypothesis by comparing patterns in abundance of Cystoseira and turf-forming algae at a number of locations in urban areas and in areas far from distinct sources of anthropogenic disturbance in the northwest Mediterranean. The second hypothesis was tested by conducting a largescale manipulative experiment, involving the experimental removal of Cystoseira and several spatial and temporal repetitions of the manipulation. Turf-forming algae were always dominant in urban areas where Cystoseira was nearly absent. In contrast, canopy algae often dominated rocky shores in relatively pristine areas of the northwest Mediterranean. The removal of Cystoseira generally caused an increase in the percentage cover of turf-forming algae and a decrease in the abundance of invertebrates. These changes were already evident 4 mo after manipulation and were consistent at the spatial and temporal scales examined in the study. Assemblages in cleared patches were qualitatively similar to those occurring where Cystoseira was naturally absent, but quantitative differences in the relative abundance of several taxa were still evident by the end of the study. These results support a cause effect relationship between anthropogenic disturbance and loss of Cystoseira in the northwest Mediterranean and allow for quantitative predictions of the indirect consequences of disturbing canopy algae for the whole understory assemblage. Management options aimed at conserving these plants should simultaneously preserve other components of the assemblage.

Anthropogenic disturbance; Canopy algae; Cystoseira; Habitat formers; Indirect effects; Large-scale experiments; Prediction; Rocky shores; Turf-forming algae.

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Bennett, B. A. and C. G. Attwood. 1991. Evidence for recovery of a surf-zone fish assemblage following the establishment of a marine reserve on the southern coast of South Africa. Marine Ecology Progress Series. 75:173-181.

Abstract:

This study was designed to establish whether populations of fish species important in the catches of rock and surf anglers increased following the proclamation of the De Hoop Marine Reserve on the southern coast of South Africa Catch per unit effort (CPUE) and size frequency distributions of angling species were monitored approximately monthly by angling from the shore at 2 sites in the reserve. At one site sampling commenced 2 yr before the reserve was established and continued 4.5 yr thereafter, allowing comparisons of periods of exploitation and protection. The other site had a long history of minimal exploitation and data collected there 2.5 to 4.5 yr after complete protection was considered to represent an unexplolted condition. Ten species accounted for 99% of the catch. Following establishment of the reserve. CPUE increased for 6 of these (galjoen Coracinus capensis, dassie Diplodus sargus, wildeperd D. cervinus, white steenbras Lithognathus lithognathus, Cape stumpnose Rhabdosargus holubi and musselcracker Sparodon durbanensis) The catch rates of 2 species (C. capensis and D. sargus) improved 4 to 5 fold within 2 yr of protection and remained at these high levels, which were similar to the unexploited catch rates. Recoveries were slower amongst the other 4 species, their catch rates reaching 30 to 60% of the unexploited level after 2.5 to 4.5 yr of protection This study provides evidence of general stock recoveries of exploited fish species in a shallow marine habitat following protection within a marine reserve.

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Berkeley, S. A., C. Chapman and S.M. Sogard. 2004. Maternal Age as a Determinant of Larval Growth and Survival in a Marine Fish, Sebastes Melanops. Ecology. 85(5): 1258-1264.

Abstract:

Relative body size has long been recognized as a factor influencing reproductive success in fishes, but maternal age has only recently been considered. We monitored growth and starvation resistance in larvae from 20 female black rockfish (Sebastes melanops), ranging in age from five to 17 years. Larvae from the oldest females in our experiments had growth rates more than three times as fast and survived starvation more than twice as long as larvae from the youngest females. Female age was a far better predictor of larval performance than female size. The apparent underlying mechanism is a greater provisioning of larvae with energy-rich triacylglycerol (TAG) lipids as female age increases. The volume of the oil globule (composed primarily of TAG) present in larvae at parturition increases with maternal age and is correlated with subsequent growth and survival. These results suggest that progeny from older females can survive under a broader range of environmental conditions compared to progeny from younger females. Age truncation commonly induced by fisheries may, therefore, have severe consequences for long-term sustainability of fish populations.

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Berkeley, S. A., M. A. Hixon, R. J. Larson and M. S. Love. 2004. Fisheries Sustainability via Protection of Age Structure and Spatial Distribution of Fish Populations. Fisheries 29(8): 23-32.

Abstract:

Numerous groundfish stocks in both the Atlantic and Pacific are considered overfished, resulting in large-scale fishery closures. Fishing, in addition to simply removing biomass, also truncates the age and size structure of fish populations and often results in localized depletions. We summarize recent research suggesting that an old-growth age structure, combined with a broad spatial distribution of spawning and recruitment, is at least as important as spawning biomass in maintaining long-term sustainable population levels. In particular, there is evidence that older, larger female rockfishes produce larvae that withstand starvation longer and grow faster than the offspring of younger fish, that stocks may actually consist of several reproductively isolated units, and that recruitment may come from only a small and different fraction of the spawning population each year. None of these phenomena is accounted for in current management programs. We examine alternative management measures that address these specific issues and conclude that the best and perhaps only way to ensure old-growth age structure and complex spatial structure in populations of groundfish is through interconnected networks of marine reserves.

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Blanchette, C. A., B. R. Broitman and S. D. Gaines. 2006. Intertidal community structure and oceanographic patterns around Santa Cruz Island, CA, USA. Marine Biology. 149:689-701.

Abstract:

Recent studies suggest that nearshore oceanographic conditions can have important effects on the structure of benthic communities. On Santa Cruz Island (SCI), CA, USA there is a persistent difference in mean annual sea surface temperature (SST) around the island due to its location at the confluence of opposing cold and warm ocean current systems. Over the course of a 4-year study (1997–2001) seawater nutrient and chl-a concentrations, algal tissue C:N ratios, recruitment and growth of filter-feeders (barnacles and mussels), and intertidal community structure were measured at six intertidal sites around the island. There were strong associations between remotely sensed SST and patterns of community structure. Macrophyte abundance was highest at sites with persistently low SST, while recruitment, abundance, and growth of filter-feeding invertebrates were strongly, positively correlated with SST. The cold-water sites were associated with higher nutrient concentrations and lower algal C:N ratios, particularly in the winter months. Values of chl-a were generally low and variable among sites, and were not correlated with the predominant SST gradient. Recruitment of barnacles and mussels was positively correlated with adult abundance across all sites. While detailed experimental studies are needed to further evaluate the mechanisms underlying community dynamics, these results indicate that the confluence of cold- and warm-water masses around SCI may determine the contrasting patterns of intertidal community structure.

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Blyth-Skyrme, R. E., P. J. Hart, M. J. Kaiser, G. Edwards-Jones and D. Palmer. 2007. Evidence for greater reproductive output per unit area in areas protected from fishing. Canadian Journal of Fisheries and Aquatic Sciences. 64:1284-1289.

Abstract:

Marine protected areas are advocated as an essential management tool to ensure the sustainable use of marine resources by providing insurance against over-exploitation and through the provision of refuge for a large biomass of sexually mature adults. Using a unique fishing gear-restriction, voluntary management system as a large-scale experiment, we found that adult scallops (Pecten maximus) within areas protected from towed bottom-fishing gear had heavier adductor muscle tissue and gonads that were 19%-24% heavier than those of scallops in fished areas, while other body and age characteristics were similar in both areas. The scallops within the protected area also occurred at a much higher abundance than adjacent, chronically fished (× 12.83) and wider commercially exploited (× 2.18) areas. These results provide evidence that the use of towed bottom-fishing gear can further exacerbate the effects of overfishing through the suppression of the reproductive potential of individuals of similar body size. These findings underline the utility of using closed areas as tools for fisheries conservation of sedentary species of commercial importance.

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Blyth-Skyrme, R. E., M. J. Kaiser, J. G. Hiddink, G. Edwards-Jones and P. J. B. Hart. 2006. Conservation benefits of temperate marine protected areas: variation among fish species. Conservation Biology. 20:811-820.

Abstract:

Marine protected areas, and other fishery management systems that impart partial or total protection from fishing, are increasingly advocated as an essential management tool to ensure the sustainable use of marine resources. Beneficial effects for fish species are well documented for tropical and reef systems, but the effects of marine protected areas remain largely untested in temperate waters. We compared trends in sport-fishing catches of nine fish species in an area influenced by a large (500-km2) towed-fishing-gear restriction zone and in adjacent areas under conventional fishery management controls. Over the period 1973-2002 the mean reported weight of above-average-sized (trophy) fish of species with early age at maturity and limited home range was greatest within the area influenced by the fishing-gear restriction zone. The reported weight of trophy fish of species that mature early also declined less and more slowly over time within the area influenced by the fishing-gear restriction zone. Importantly, the mean reported weight of trophy fish of species that mature late and those that undertake extensive spatial movements declined at the same rate in all areas. Hence these species are likely to require protected areas >500 km2 for effective protection. Our results also indicated that fish species with a localized distribution or high site fidelity may require additional protection from sport fishing to prevent declines in the number or size of fish within the local population.

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Bobko, S.J. and S.A. Berkeley. 2004. Maturity, ovarian cycle, fecundity, and age-specific parturition of black rockfish (Sebastes melanops). Fisheries Bulletin 102:418-429.

Abstract:

From 1995 to 1998, we collected female black rockfish (Sebastes melanops) off Oregon in order to describe their basic reproductive life history and determine age-specific fecundity and temporal patterns in parturition. Female black rockfish had a 50% probability of being mature at 394 mm fork length and 7.5 years-of-age. The proportion of mature fish age 10 or older significantly decreased each year of this study, from 0.511 in 1996 to 0.145 in 1998. Parturition occurred between mid-January and mid-March, and peaked in February. We observed a trend of older females extruding larvae earlier in the spawning season and of younger fish primarily responsible for larval production during the later part of the season. There were differences in absolute fecundity at age between female black rockfish with prefertilization oocytes and female black rockfish with fertilized eggs; fertilized-egg fecundity estimates were considered superior. The likelihood of yolked oocytes reaching the developing embryo stage increased with maternal age. Absolute fecundity estimates (based on fertilized eggs) ranged from 299,302 embryos for a 6-year-old female to 948,152 embryos for a 16-year-old female. Relative fecundity (based on fertilized eggs) increased with age from 374 eggs/g for fish age 6 to 549 eggs/g for fish age 16.

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Bohnsack, J. A.. 2000. A comparison of the short-term impacts of no-take marine reserves and minimum size limits. Bulletin of Marine Science 66(3): 635-650.

Abstract:

Establishing no-take marine reserves (NTRs) displaces fishing effort to surrounding areas, creating concerns about short-term impacts on resources and fishers before long-term benefits can accrue. Models were developed to compare the effects of short-term displacement caused by of NTRs to effects of minimum size limits (MSLs), one of the most widely applied management measures in the southeastern U.S. Projected impacts on resource protection and fishers were assessed on the basis of the portion of a population either protected or legally available to fishing. In all cases, existing MSLs had greater impact on total numbers of fish landed (reduced by 38 to 70%) than on the weight of total landings (reduced by 14 to 26%). NTRs protected sedentary species in approximate proportion to the total habitat closed to fishing but provided less protection as species mobility increased. These differences in protection due to mobility were greater for reserves covering small percentages of total habitat. Predicted short-term displacement impacts on fishers were low for reserves covering small percentages of the total habitat, but they increased exponentially as the percentage of total habitat closed increased. Displacement impacts were predicted to be highest for fishers pursuing sedentary species and decreased for more mobile species. Detrimental impacts to surrounding habitat from displacement depended on initial fishery conditions, gear type, and the total proportion of habitat closed. Although more fishers are affected by the no-take rule, concerns about short-term displacement impacts appear to be exaggerated. Some opposition to establishing NTRs may result in part because the no-take provision is more difficult to circumvent than other regulations. When combined with traditional management tools, no-take reserves offer increased flexibility for supporting fisheries and protecting resources.

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Botsford, L. W. 2001. Physical influences on recruitment to California Current invertebrate populations on multiple scales. ICES Journal of Marine Science. 58:1081-1091.

Studies of recruitment to Dungeness crab (Cancer magister) and red sea urchin (Strongylocentrotus franciscanus) populations have focused on recruitment variability on interannual, 1000-km scales. These studies have identified correlations between recruitment and variables indicating ENSO conditions and wind-forced larval transport. On longer scales, our understanding of biologically important physical variability in the California Current has recently been enhanced by an appreciation of semi-basin, decadal changes. Intensification of the Aleutian low-pressure zone in the mid-1970s had a clear positive effect of biological productivity in the Gulf of Alaska, and less obvious negative effects on productivity in the California Current. On shorter scales, an increasing appreciation of the effect of dispersal patterns on population dynamics and the potential of spatially explicit management schemes provide the impetus for studying processes such as alongshore spatial variability in recruitment and the underlying daily variability in circulation over 100-km distances. In the 1980s, physical studies of coastal circulation in response to daily fluctuations in upwelling winds identified brief periods of northward, onshore flow interrupting the offshore, southward flows associated with active upwelling. In the 1990s, concurrent monitoring of biological and physical conditions revealed that these flows transport late-stage invertebrate larvae from a retention zone in the lee of a local promontory to settlement locations, producing specific spatial patterns of recruitment. Variability in recruitment of both crabs and sea urchins is thus driven by daily temporal variability in upwelling winds and 100-km spatial variability in coastal topography. Interannual recruitment variability appears to depend on ENSO-related biological productivity and larval transport in ways that vary among species, but are not completely understood. Observations are consistent with coastwide, interannual variability being driven by biological productivity (i.e. ENSO/non-ENSO conditions), while the upwelling relaxation mechanism sets the spatial scale, and decadal, semi-basin variability modulates the frequency of ENSO conditions.

Dungeness crab; ENSO; marine reserves; red sea urchin; regime shift; scales; settlement; upwelling relaxation.

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Botsford, L.W., F. Micheli, and A. Hastings. 2003. Principles for the Design of Marine Reserves. Ecological Applications 13(1) Supplement: S25-S31

Abstract:

The theory underlying the design of marine reserves, whether the goal is to preserve biodiversity or to manage fisheries, is still in its infancy. For both of these goals, there is a need for general principles on which to base marine reserve design, and because of the paucity of empirical experience, these principles must be based on models. However, most of the theoretical studies to date have been specific to a single situation, with few attempts to deduce general principles. Here we attempt to distill existing results into general principles useful to designers of marine reserves. To answer the question of how fishery management using reserves compares to conventional management, we provide two principles: (1) the effect of reserves on yield per recruit is similar to increasing the age of first capture, and (2) the effect of reserves on yield is similar to reducing effort. Another two principles answer the question of how to design reserve configurations so that species with movement in various stages will be sustainable: (3) higher juvenile and adult movement lowers sustainability of reserves for biodiversity, but an intermediate level of adult movement is required for reserves for fishery management, and (4) longer larval dispersal distance requires larger reserves for sustainability. These principles provide general guidelines for design, and attention to them will allow more rapid progress in future modeling studies. Whether populations or communities will persist under any specific reserve design is uncertain, and we suggest ways of dealing with that uncertainty.

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Brown, P. J. and R. B. Taylor. 1999. Effects of trampling by humans on animals inhabiting coralline algal turf in the rocky intertidal. Journal of Experimental Marine Biology and Ecology. 235:45-53.

Abstract:

This paper investigates the effects of trampling by humans on the fauna associated with articulated coralline algal turf. Patches of intertidal turf in a low-use area of the Cape Rodney to Okakari Point Marine Reserve (in north-eastern New Zealand) were experimentally trampled over 5 days at three levels that fell within those measured in a part of the reserve subject to heavy 5 visitor use. Two days after trampling ended there were ~ 2 * 105 individual macrofauna (.500 2 mm) per m in control plots, but densities declined with increasing trampling intensity in the treatment plots, and were reduced to 50% of control values at the highest trampling intensity. Densities of five of the eight commonest taxa were negatively correlated with trampling intensity, with polychaetes being particularly susceptible to low levels of trampling. Three months after trampling ended densities of all taxa had returned to control values, with the exception of polychaetes. Reductions in animal densities are tentatively attributed to the loss of turf and associated sand caused by trampling, rather than direct destruction of the organisms. Given the likely importance of these abundant and productive animals in the rocky reef ecosystem, and their vulnerability to low levels of trampling by humans, we conclude that the effective management of marine protected areas may necessitate total exclusion of humans in some cases.

Algae; Coralline turf; Epifauna; Human impact; Intertidal; New Zealand; Marine reserve; Trampling.

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Byers, J. E. 2005. Marine reserves enhance abundance but not competitive impacts of a harvested nonindigenous species. Ecology. 86:487-500.

Marine reserves are being increasingly used to protect exploited marine species. However, blanket protection of species within a reserve may shelter nonindigenous species that are normally affected by harvesting, intensifying their impacts on native species. I studied a system of marine reserves in the San Juan Islands, Washington, USA, to examine the extent to which marine reserves are invaded by nonindigenous species and the consequences of these invasions on native species. I surveyed three reserves and eight non-reserves to quantify the abundance of intertidal suspension-feeding clam species, three of which are regionally widespread nonindigenous species (Nuttallia obscurata, Mya arenaria, and Venerupis philippinarum). Neither total nonindigenous nor native species' abundance was significantly greater on reserves. However, the most heavily harvested species, V. philippinarum, was significantly more abundant on reserves, with the three reserves ranking highest in Venerupis biomass of all 11 sites. In contrast, a similar, harvested native species (Protothaca staminea) did not differ between reserves and non-reserves.

I followed these surveys with a year-long field experiment replicated at six sites (the three reserves and three of the surveyed non-reserve sites). The experiment examined the effects of high Venerupis densities on mortality, growth, and fecundity of the confamilial Protothaca, and whether differences in predator abundance mitigate density-dependent effects. Even at densities 50% higher than measured in the field survey, Venerupis had no direct effect on itself or Protothaca; only site, predator exposure, and their interaction had significant effects. Analyses incorporating environmental variables tracked at each site indicated that crab biomass most heavily influenced clam responses, causing lower growth of both species and higher mortality of Venerupis, whose annualized loss rate was 50% when exposed to predators. A laboratory prey choice experiment indicated that Cancer productus, an influential intertidal crab predator, favored small adult Venerupis at least 1.7 times over Protothaca. Venerupis' high susceptibility to excavating crab and human predators, as well as its faster growth compared to Protothaca can be explained by its shallower burial depth. By growing quickly and residing near the surface, Venerupis apparently absorbs the brunt of harvest pressure while Protothaca maintains high biomass even outside of reserves.

apparent competition; clams; exotic species; fisheries; marine protected areas; mixed effects models; Nuttallia obscurata; Protothaca staminea; San Juan Islands; Washington (USA); spatially replicated experiments; Tapes japonica; Venerupis philippinarum.

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Carr, M.H., J.E. Neigel, J.A. Estes, S. Andelman, R.R. Warner, and J.L. Largier. 2003. Comparing Marine and Terrestrial Ecosystems: Implications for the Design of Coastal Marine Reserves. Ecological Applications 13(1) Supplement: S90-S107.

Abstract:

Concepts and theory for the design and application of terrestrial reserves is based on our understanding of environmental, ecological, and evolutionary processes responsible for biological diversity and sustainability of terrestrial ecosystems and how humans have influenced these processes. How well this terrestrial-based theory can be applied toward the design and application of reserves in the coastal marine environment depends, in part, on the degree of similarity between these systems. Several marked differences in ecological and evolutionary processes exist between marine and terrestrial ecosystems as ramifications of fundamental differences in their physical environments (i.e., the relative prevalence of air and water) and contemporary patterns of human impacts. Most notably, the great extent and rate of dispersal of nutrients, materials, holoplanktonic organisms, and reproductive propagules of benthic organisms expand scales of connectivity among nearshore communities and ecosystems. Consequently, the ''openness'' of marine populations, communities, and ecosystems probably has marked influences on their spatial, genetic, and trophic structures and dynamics in ways experienced by only some terrestrial species. Such differences appear to be particularly significant for the kinds of organisms most exploited and targeted for protection in coastal marine ecosystems (fishes and macroinvertebrates). These and other differences imply some unique design criteria and application of reserves in the marine environment. In explaining the implications of these differences for marine reserve design and application, we identify many of the environmental and ecological processes and design criteria necessary for consideration in the development of the analytical approaches developed elsewhere in this Special Issue.

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Carson, H. S. and B. T. Hentschel. 2006. Estimating the dispersal potential of polychaete species in the Southern California Bight: implications for designing marine reserves. Marine Ecology Progress Series. 316:105-113.

Using known and inferred life-history information, we estimated the dispersal potential of 501 polychaete species sampled during a 1998 monitoring study in the Southern California Bight. We tested the hypothesis that species having life-history traits that suggest long-distance dispersal will be encountered more frequently throughout the region than will species having life histories that suggest limited dispersal. When all 501 species and all 200 sampling sites were analyzed, occurrence frequency (percentage of sites at which a species was collected) was not significantly related to dispersal potential. When data from 53 shelf sites in the Channel Islands were analyzed separately from collections at 147 mainland-shelf sites, there was a significant positive relationship between dispersal potential and occurrence frequency at the island sites but not at the mainland sites. Of the 501 species, 119 were collected only at island sites, 98 were found only at mainland sites, and 284 were found at both island and mainland sites. The majority of the 'island only' species had life-history traits indicating low dispersal potential. In contrast, only 13% of the 'mainland only' species were categorized as having low dispersal potential. The 'cosmopolitan' species had a broad range of dispersal potential. Models indicate that efforts to conserve biodiversity by establishing Marine Protected Areas (MPAs) must consider species' dispersal. In the shelf communities of the Southern California Bight, networks of small reserves that are located in existing areas of high diversity should succeed in the Channel Islands, where the majority of polychaete species tend to have limited dispersal potential. On the mainland shelf, however, designing effective MPAs will be more challenging due to the prevalence of species that have a greater potential for long-distance dispersal to or from unprotected sites.

Dispersal; Larval ecology; Life history; Marine Protected Area; Marine reserve; Polychaete.

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Castilla, J. C. 1999. Coastal marine communities: trends and perspectives from human-exclusion experiments. Trends in Ecology and Evolution. 14:280-283.

The ecological roles of humans in marine communities have been poorly studied. Humans have special characteristics, such as culture, and are perceived as complex ecological actors. Observations and experiments conducted in coastal (rocky intertidal and nearshore) 'no-take' areas or reserves in Chile and around the world have permitted a better understanding of the role played by humans as top predators and the resulting trophic-cascade effects along the food-webs. These studies have revealed an urgent need to incorporate humans into ecological studies and have helped to promote links between ecology and social sciences.

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Casu, D., G. Ceccherelli , M. Curini-Galletti and A. Castelli. 2006. Human exclusion from rocky shores in a mediterranean marine protected area (MPA): An opportunity to investigate the effects of trampling. Environmental Research. 62:15-32.

Abstract:

The effect of human trampling on the abundance of small invertebrates inhabiting rocky shallow bottoms was studied at Asinara Island MPA. To this aim we have conducted two experiments. The first was a quantitative study and tested the hypothesis that small invertebrates are more abundant at no-entry locations than at the location visited by tourists through time (before, during and after tourist season). The second was a manipulative experiment and tested the hypothesis that the abundance of small invertebrates is indirectly related to experimental trampling intensities. The effect due to tourist visitation was not highlighted on overall assemblages, suggesting that present seasonal tourist load at the MPA does not cause a significantly negative effect on the zoobenthic community studied. Although tourists exhibited trampling activity at the visited location, none of taxa examined showed a significant lower abundance during and strictly after the end of seasonal tourism peak in the visited location, rather than at control locations. However, results obtained with the second experiment suggested that the effects of different experimental trampling intensities on small invertebrates were variable among taxa. The experimental trampling caused immediate declines in the density of tanaids, nematodes, acari, bivalves, gammarids, echinoderms, isopods, and harpacticoids. For some of these taxa a recovery in abundance was observed within one month.

Asinara island; Benthic invertebrates; Marine protected area; Mediterranean sea; Rocky shore; Trampling.

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Claudet, J., C. W. Osenberg, L. Benedetti-Cecchi, P. Domenici, J. A. Garcia-Charton, A. Perez-Ruzafa, F. Badalamenti, J. Bayle-Sempere, A. Brito, F. Bulleri, J. M. Culioli, M. Dimech, J. M. Falcon, I. Guala, M. Milazzo, J. Sanchez-Meca, P. J. Somerfield, B. Stobart, F. Vandeperre, C. Valle and S. Planes. 2008. Marine reserves: size and age do matter. Ecology Letters. 11:481-489.

Marine reserves are widely used throughout the world to prevent overfishing and conserve biodiversity, but uncertainties remain about their optimal design. The effects of marine reserves are heterogeneous. Despite theoretical findings, empirical studies have previously found no effect of size on the effectiveness of marine reserves in protecting commercial fish stocks. Using 58 datasets from 19 European marine reserves, we show that reserve size and age do matter: Increasing the size of the no-take zone increases the density of commercial fishes within the reserve compared with outside; whereas the size of the buffer zone has the opposite effect. Moreover, positive effects of marine reserve on commercial fish species and species richness are linked to the time elapsed since the establishment of the protection scheme. The reserve size-dependency of the response to protection has strong implications for the spatial management of coastal areas because marine reserves are used for spatial zoning.

Asymmetrical analysis of variance; coastal marine ecosystems; commercial species; fish assemblages; heterogeneity; marine protected area; marine reserve age; marine reserve design; marine reserve network; marine reserve size; weighted meta-analysis.

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Cole, R. G., T. M. Ayling and R. G. Creese. 1990. Effects of marine reserve protection at Goat Island, northern New Zealand. New Zealand Journal of Marine and Freshwater Research. 24:197-210.

Abstract:

The possible effects that marine reserve protection has had on densities of some reef fish and large invertebrates were investigated near Leigh (north-eastern New Zealand) by a series of sampling programmes between 1976 and 1988. Fish counts at intervals during the 6 years after the initial establishment of the Cape Rodney to Okakari Point Marine Reserve in 1975 suggested that red moki (Cheilodactylus spectabilis) had increased in abundance whereas five others had remained at approximately constant densities. A comparison of data between 1978 and 1988 also revealed few consistent differences in fish abundances. A detailed survey in 1988 between sites inside and outside the marine reserve showed no clear patterns for sea urchins (Evechinus chloroticus) and several fish; trends for increased abundances in the marine reserve of fish such as snapper Pagrus (=Chrysophrys) auratus, blue cod (Parapercis colias), and red moki; a very striking increase in numbers of rock lobsters (Jasus edwardsii) within the marine reserve; and an obvious trend for increased size of snapper in the marine reserve. Most of the trends, however, were not statistically significant, owing largely to the low power of the tests used. Although it is now generally accepted that the creation of marine reserves such as the one at Leigh results in increased abundances of certain organisms, our study highlights the difficulty of rigorously demonstrating this, especially for patchily distributed and mobile fish species.

Marine reserve; fish; abundance; rock lobster, sea urchin.

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Coleman, F.C. , W.F. Figueira, J.S. Ueland and L.B. Crowder. 2004. The Impact of United States Recreational Fisheries on Marine Fish Populations. Scienceexpress. 3pp.

Abstract:

We evaluate the commercial and recreational fishery landings over the past 22 years, first at the national level, second for populations of concern (those that are overfished or experiencing overfishing), and finally by region. Recreational landings in 2002 account for 4% of total marine fish landed in the USA. With large industrial fisheries excluded (e.g., menhaden and pollock), the recreational component rises to 10%. Among populations of concern, recreational landings in 2002 account for 23% of the total nationwide, rising to 38% in the South Atlantic and 64% in the Gulf of Mexico. Moreover, it affects many of the most valued overfished species, including red drum, bocaccio, and red snapper, all of which are taken primarily in the recreational fishery.

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Collins, M.R., T.I.J. Smith, W.E. Jenkins, M.R. Denson. 2002. Small Marine Reserves May Increase Escapement of Red Drum. Fisheries 27(2): 20-24.

Abstract:

An experimental stock enhancement program was conducted in Port Royal Sound estuary, South Carolina, in which cultured juvenile red drum (Sciaenops ocellatus, 2-3 cm TL, ~40 days old) were released into a system of shallow tidal creeks that flow into the Colleton River. All fish were immersed in oxytetracycline (OTC) prior to release to produce an identifiable, chemical mark on the otoliths. The release area was typical of primary nursery habitat in this region. For four years post-stocking, fish were collected throughout the sound using hook and line, spear, and trammel net. Otoliths were examined for OTC marks to determine which fish were of hatchery origin. It was found that while dispersal was substantial, many stocked fish stayed in the general area of release (1.8 x 3.2 km) until reaching the age of maturity (~age 3) when they left the estuary, and at all ages they were mixed with wild fish. This suggests that relatively small areas containing the appropriate suite of habitat types could be designated as marine reserves (no-take zones) in order to increase escapement of red drum, thus enhancing recruitment to the spawning stock. Establishing a system of these very small reserves in a number of estuaries would minimize interference with anglers while assisting recovery of red drum stocks, and perhaps enhancing stocks of other estuarine species as well.

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Compas, E., B. Clarke, C. Cutler and K. Daish. 2007. Murky waters: Media reporting of marine protected areas in South Australia. Marine Policy. 31:691-697.

Abstract:

Given the public’s limited knowledge of marine environments, informing the public about marine protection presents a unique challenge. Studies have shown a well-informed public is more likely to support environmental issues and that newspapers, in particular, are considered a credible media source. This research investigates media representations of current South Australian efforts to establish a marine protected area (MPA). Articles from five newspapers between 1999 and 2006 were examined for content in the following areas: local marine ecology, the policy process of MPA establishment and stakeholder views. The research found that newspapers concentrated their reporting on opposing stakeholders, opinions and were largely ineffective in conveying the significance of the local marine ecology, the economic benefits of the MPA, and the delayed establishment process. These information gaps have left the public poorly informed, and therefore, there is unlikely to be significant pressure to overcome the continued delays in the establishment process.

 Marine protected areas; Media; Content analysis; South Australia.

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Cooke, S. J., A. J. Danylchuck, S. E. Danylchuck, C. D. Suski and T. L. Goldberg. 2006. Is catch-and-release recreational angling compatible with no-take marine protected areas? Ocean and Coastal Management. 49:342-354.

Abstract:

Marine protected areas (MPAs) have become a common conservation and management tool for reducing exploitation from the commercial and recreational fisheries sectors. However, the recreational fisheries sector has the potential to be compatible with no-take MPAs when catchand- release angling is practiced because, in theory, no fish are actually harvested. This presumes that the effects of catch-and-release angling and related activities do not cause appreciable declines in fish populations as a result of direct mortality, sub-lethal effects, or indirect effects on fish habitats, or other problems contrary to the goal of a given MPA. Here, we explore the idea that recreational catch-and-release angling may be compatible with some no-take MPAs provided there are no substantive negative ecological consequences. We argue that it is not currently possible to answer definitively the question of whether recreational catch-and-release fisheries can be compatible with no-take MPAs. Mortality rates of released fish vary extensively (between zero and near 100%) and are influenced by a number of factors including environmental conditions, fishing gear, angler behavior, and species-specific characteristics. Nevertheless, research in the field of catch-and-release is beginning to show that certain handling techniques can significantly reduce post-release mortality in fish. With appropriate regulation and angler education, catch-and-release could help enhance conservation and management goals associated with MPAs while maintaining public support and providing alternative tourism-based revenues for displaced fishers. Until sufficient data are available, research should focus on contrasting the fish community characteristics in regions with no fishing and those that permit catch-and-release fishing (i.e., opportunistic observations and controlled manipulations) as well as population-level mathematical modeling to assess the effects of angling on long-term population viability and ecosystem dynamics. Additional efforts should focus on education and outreach that provide anglers and fishing guides with the best available information to reduce catch-and-release mortality, sublethal angling-induced impairments, and broader effects on aquatic environments.

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Cooke, S.J. and I.G. Cowx. 2004. The Role of Recreational Fishing in Global Fish Crises. Bioscience 54(9): 857-859.

Abstract:

Exploitation of fishery resources has become a major conservation issue on a global scale. Commercial fisheries have been repeatedly blamed for the worldwide declines in fish populations. However, we contend that the recreational fishing sector also has the potential to negatively affect fish and fisheries. Here we present evidence to show that both recreational and commercial fishing sectors deserve consideration as contributors to the exploitation of fish in marine and inland waters. The lack of global monitoring and compiling of statistics on recreational fishing participation, harvest, and catch-and-release has retarded our ability to understand the magnitude of this fishing sector. Using data from Canada, we estimate that the potential contribution of recreational fish harvest around the world may represent approximately 12 percent of the global fish harvest. Failure to recognize the potential contribution of recreational fishing to fishery declines, environmental degradation, and ecosystem alterations places ecologically and economically important resources at risk. Elevating recreational fishing to a global conservation concern would facilitate the development of strategies to increase the sustainability of this activity.

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Costello, C. and S. Polasky. In Press. Optimal harvesting of stochastic spatial resources. Journal of Environmental Economics and Management.

We characterize the optimal harvest of a renewable resource in a generalized stochastic spatially explicit model. Despite the complexity of the model, we are able to obtain sharp analytical results. We find that the optimal harvest rule in general depends upon dispersal patterns of the resource across space, and only in special circumstances do we find a modified golden rule of growth that is independent of dispersal patterns. We also find that the optimal harvest rule may include closure of some areas to harvest, either on a temporary or permanent basis (biological reserves). Reserves alone cannot correct open access, but may, under sufficient spatial heterogeneity and connectivity, increase profits if appropriate harvest controls are in place outside of reserves.

Marine reserves; Spatial externalities; Stochastic dynamic programming; Renewable resources; Bioeconomic modeling.

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Cote, I.M., I. Mosqueira, and J.D. Reynolds. 2001. Effects of marine reserve characteristics on the protection of fish populations: a meta-analysis. Journal of Fish Biology 59(A): 178-189.

Abstract:

Meta-analyses of published data for 19 marine reserves reveal that marine protected areas enhance species richness consistently, but their effect on fish abundance is more variable. Overall, there was a slight (11%) but significant increase in fish species number inside marine reserves, with all reserves sharing a common effect. There was a substantial but non-significant increase in overall fish abundance inside marine reserves compared to adjacent, non-reserve areas. When only species that are the target of fisheries were considered, fish abundance was significantly higher (by 28%) within reserve boundaries. Marine reserves vary significantly in the extent and direction of their response. This variability in relative abundance was not attributable to differences in survey methodology among studies, nor correlated with reserve characteristics such as reserve area, years since protection, latitude nor species diversity. The effectiveness of marine reserves in enhancing fish abundance may be largely related to the intensity of exploitation outside reserve boundaries and to the composition of the fish community within boundaries. It is recommended that studies of marine reserve effectiveness should routinely report fishing intensity, effectiveness of enforcement and habitat characteristics.

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Dalton, T. M. 2005. Beyond biogeography: a framework for involving the public in planning of U.S. marine protected areas. Conservation Biology. 19:1392-1401.

Abstract:

Planning of marine protected areas (MPAs) is highlighted in the conservation literature but is not explored in much detail. Many researchers acknowledge the importance of involving the public in MPA planning, but there is limited guidance on how to do this in an effective manner. I present a framework for involving the public in planning of U.S. MPAs. Derived from empirically and theoretically based research on public participation in U.S. natural resource management, this framework is composed of factors that influence the success of participatory processes: active participant involvement, complete information exchange, fair decision making, efficient administration, and positive participant interactions. Processes incorporating these factors will produce decisions that are more likely to be supported by stakeholders, meet management objectives, and fulfill conservation goals. This framework contributes to the MPA social science literature and responds to calls in the conservation literature to increase the use of social science research to inform conservation decision making.

 Ecosystem-based management; governance of marine protected areas; public participation; stakeholder involvement.

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Dalton, M.T. 2004. An approach for integrating economic impact analysis into the evaluation of potential marine protected area sites. Journal of Environmental Management 70(3): 333-349.

Abstract:

Marine protected areas (MPAs) are one tool that can be used in the comprehensive management of human activities in areas of the ocean. Although researchers have supported using MPAs as an ecosystem management tool, scientific research on MPAs in areas other than fisheries and fisheries management is limited. This paper presents a model for designing marine protected areas that protect important components of the ecosystem while minimizing economic impacts on local communities. This model combines conservation principles derived specifically for the marine environment with economic impact assessment. This integrated model allows for consideration of both fishery and non-fishery resources and activities such as shipping and recreational boating. An illustration of the model is presented that estimates the total economic impacts on Massachusetts' coastal counties of restricting fishing and shipping at certain sites in an area in the southern Gulf of Maine. The results suggest that the economic impacts on the region would differ according to the site in which shipping and fishing were restricted. Restricting activities in certain sites may have considerable impacts on local communities. The use of the model for evaluating and comparing potential MPA sites is illustrated through an evaluation of three different policy scenarios. The scenarios demonstrate how the model could be used to achieve different goals for managing resources in the region: protecting important components of the ecosystem, minimizing economic impacts on the local region, or a combination of the two.

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Dayton, P.K., E. Sala, M.J. Tegner and S. Thrush. 2000. Marine reserves: Parks, baselines, and fishery enhancement. Bulletin of Marine Science 66(3): 617-634.

Abstract:

Coastal zones are usually managed with two main objectives: (1) conservation/maintenance of biodiversity and intrinsic ecosystem services and (2) maintenance of sustainable fisheries. The management needs that can be met with marine protected areas fall into corresponding categories. First, fully protected (that is, no-take) reserves--parks--offer banchmarks and protect ecosystem integrity while encouraging research, education, and aesthetic appreciation of nature. Second, by allowing focused local control of human impacts, marine protected areas can be used to focus more intense local management designed to increase yield and allow research to help define sustainability and protect against uncertainty by using carefully managed fisheries as a research tool. We have been gambling with the future by establishing a poor balance between short-term profit and long-term risks. The absence of meaningful, fully protected reserves has produced a situation in which there are virtually no areas north of the Antarctic in the world's oceans that have exploitable resources where scientists can study natural marine systems. In most areas the higher-order predators and many other important species have been virtually eliminated; many benthic habitats have been much changed by fishing activities. Without solid data documenting changes through time, the relative merits of various causes and effects that operate in complex ecological systems can always be argued. Without natural systems important questions cannot be studied--for example, how the ecosystem roles of various species can be assessed, how they can be managed in a sustainable manner, and how we can evaluate resilience or relative rates of recovery.

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Denny, C. M. and R. C. Babcock. 2004. Do partial marine reserves protect reef fish assemblages? Biological Conservation. 116:119-129.

Abstract:

Fish assemblages in the Mimiwhangata Marine Park, an area closed to commercial fishing but open to most forms of recreational fishing, were compared with adjacent fished areas. Two survey methodologies were used; baited underwater video and underwater visual census. Snapper (Pagrus auratus), the most heavily targeted fish species in the region, showed no difference in abundance or size between the Marine Park and adjacent control areas. When compared to the fully no-take Poor Knights Island Marine Reserve and two other reference areas open to all kinds of fishing (Cape Brett and the Mokohinau Islands), the abundance and size of snapper at the Marine Park were most similar to fished reference areas. In fact, the Marine Park had the lowest mean numbers and sizes of snapper of all areas, no-take or open to fishing. Baited underwater video found that pigfish (Bodianus unimaculatus), leatherjackets (Parika scaber) and trevally (Pseudocaranx dentex) were significantly more common in the Marine Park, than in the adjacent control areas. However, none of these species are heavily targeted by fishers. Underwater visual census found similar results with five species significantly more abundant in the Marine Park and five species more abundant outside the Marine Park. The lack of any recovery by snapper within the Marine Park, despite the exclusion of commercial fishers and restrictions on recreational fishing, indicates that partial closures are ineffective as conservation tools. The data suggest fishing pressure within the Marine Park is at least as high as at other ‘fished’ sites.

 Marine protected area; Mimiwhangata Marine Park; Pagrus auratus; Snapper; New Zealand; Gear restrictions.

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Diaz, D., M. Zabala, C. Linares, B. Hereu and P. Abello. 2005. Increased predation of juvenile European spiny lobster (Palinurus elephas) in a marine protected area. New Zealand Journal of Marine and Freshwater Research. 39:447-453.

Abstract:

One of the aims of Mediterranean marine protected areas (MPAs) is to increase populations of exploited species, such as the European spiny lobster (Palinurus elephas), which is considered a key species for its commercial and ecological value. Monitoring of temporal patterns in abundance of early benthic stages of P. elephas indicated that predation may be higher inside the Medes Islands MPA relative to adjacent control sites. Tethering experiments were performed to test whether predation rates actually differed within and outside the MPA. Relative mortality of recently-settled juveniles inside the MPA was much higher than in control sites in adjacent non-protected areas. Treatments with and without shelter indicated that predation on recently-settled juvenile spiny lobsters was moderated by the availability of suitable shelter. The decline or absence of fish predators in the fished area may be the reason why juvenile lobsters outside the MPA experience lower predation than within the MPA.

Predation; Palinurus elephas; marine protected areas; spiny lobster; shelter; Mediterranean Sea

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Fanshawe, S., G. R. Vanblaricom and A. A. Shelly. 2003. Restored top carnivores as detriments to the performance of marine protected areas intended for fishery sustainability: a case study with red abalones and sea otters. Conservation Biology. 17:273-283.

Abstract:

Marine protected areas are possible solutions to the problems of protecting the integrity of marine ecosystems and of sustaining harvested marine populations. We report demographic data for red abalones (Haliotis rufescens) at nine sites along the California coast. Six of our sites are within marine protected areas, and four of those six sites are occupied by sea otters (Enhydra lutris). Sea otters are known abalone predators and are believed to have an important role in facilitating biodiversity within coastal kelp forest communities along the North Pacific Rim. We asked whether marine protected areas intended to conserve ecosystems are compatible with use of marine protected areas for abalone fishery sustainability. We found that both sea otters and recreational harvest alter the density, size distribution, and microhabitat distribution of red abalones in qualitatively similar ways. Red abalone populations in marine protected areas outside the current sea otter range have higher density, are composed of larger individuals, and occur in moreopen microhabitats compared with populations in locations lacking sea otters but subject to harvest and with populations in locations with sea otters. The effects of sea otters are stronger than the effects of harvest. Characterization of harvest effects on density may be confounded by other uncontrolled factors. We conclude that coastal marine protected areas off California cannot enhance abalone fisheries if, in the interest of ecosystem integrity, they also contain sea otters. Where restored top carnivores limit the sustainability of commodity harvest, it may be possible to resolve conflicts with two categories of spatially segregated, single-use marine protected areas, one focusing on ecosystem restoration and the other on fishery development.

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Fernandez, M. and J. C. Castilla. 2005. Marine conservation in Chile: historical perspective, lessons, and challenges. Conservation Biology. 19.

Abstract:

Chile is one of the world’s leading countries in landings (catch) of marine resources. The pioneer studies of human impacts on coastal marine communities provided the scientific basis on which to establish novel resource management strategies for exploited wild populations but were not used to develop a comprehensive marine conservation plan that would also include no-take areas. We reviewed the development of marine conservation actions since approximately 1970 to date, focusing on the (1) complex legal framework for establishment of marine protected areas, (2) scientific grounds that provided the impetus to establish areas where exploitation is regulated, (3) private efforts that were critical to creating the first marine protected areas, and (4) lessons and constraints derived from this process as well as the challenges ahead. The existing legal tools for the protection of the ocean include natural sanctuaries, marine reserves, marine parks, national monuments, and management and exploitation areas for benthic resources. These instruments may be applied in coastal marine protected areas. It is remarkable that most of the existing marine protected areas in Chile are sponsored and administered by private organizations. We think the sequence in which the development of the different conservation instruments occurred, with a high priority reserved for initiatives tending to promote exploitation of the ocean (aquaculture and fisheries), poses challenges and constraints for establishing a network of marine protected areas that combine such apparently diametrically opposing goals as exploitation and preservation of marine species. More recently, the value of preserving biodiversity became evident with the creation of the first marine parks. We encourage more scientific information on patterns of biodiversity, biological processes, and assessment of human impact to be incorporated in the process to reach the goal of preserving 10% of the representative marine habitats along Chile’s coast.

 Management areas; marine parks; marine protected areas.

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Field, J. C., A. E. Punt, R. D. Methot and C. J. Thomson. 2006. Does MPA mean 'Major Problem for Assessments'? Considering the consequences of place-based management systems. Fish and Fisheries. 7:284-302.

Abstract:

Marine protected areas (MPAs) have been increasingly proposed, evaluated and implemented as management tools for achieving both fisheries and conservation objectives in aquatic ecosystems. However, there is a challenge associated with the application of MPAs in marine resource management with respect to the consequences to traditional systems of monitoring and managing fisheries resources. The place-based paradigm of MPAs can complicate the population-based paradigm of most fisheries stock assessments. In this review, we identify the potential complications that could result from both existing and future MPAs to the science and management systems currently in place for meeting conventional fisheries management objectives. The intent is not to evaluate the effects of implementing MPAs on fisheries yields, or even to consider the extent to which MPAs may achieve conservation oriented objectives, but rather to evaluate the consequences of MPA implementation on the ability to monitor and assess fishery resources consistent with existing methods and legislative mandates. Although examples are drawn primarily from groundfish fisheries on the West Coast of the USA, the lessons are broadly applicable to management systems worldwide, particularly those in which there exists the institutional infrastructure for managing resources based on quantitative assessments of resource status and productivity.

Fisheries assessment; fisheries management; fish stock; marine protected area; spatial model.

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Fisher, J. A. and K. T. Frank. 2004. Abundance-distribution relationships and conservation of exploited marine fishes. Marine Ecology Progress Series. 279:201-213.

Abstract:

The effects of human exploitation on macroecological patterns have received little attention, although such investigations may highlight unique spatial and temporal changes characteristic of species and assemblages subject to persistent disturbance. In unexploited systems (mainly among temperate avifauna) positive relationships between local abundance and geographic distribution are prevalent for individual species through time (intraspecific pattern) and among species during fixed time periods (interspecific pattern). We investigated intraspecific and interspecific relationships for 24 common marine fishes on the Scotian Shelf and Bay of Fundy, Canada, some of which have been commercially exploited for several decades. Based on extensive fisheries-independent trawl survey data from 1970 to 2001, 16 of the 34 stocks, comprising 13 species, exhibited significant positive intraspecific relationships. Significant relationships were associated mainly with those stocks that demonstrated significant temporal trends in both abundance and geographic distribution. The time-averaged (32 yr) interspecific relationship was positive and significant at the largest scale examined. Significant annual interspecific relationships were also detected over 26 yr. Surprisingly, the slopes of the annual relationships increased systematically and doubled through time, probably due to size-selective exploitation, shifting target species, and associated species interactions. In contrast to previous studies, our results indicate that the contributions of individual species to the interspecific relationship can change through time, and these changes dramatically alter the interspecific  abundance–distribution relationship. Temporal trends in the interspecific relationship have not previously been reported, and appear to be due to the large spatial- and temporal-scale effects of exploitation.

Exploited fisheries; Geographical range; Macroecology; Management; Marine protected area; MPA; Marine reserve; Range contraction; Scotian Shelf.

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Fisher, R., S. M. Sogard and S. A. Berkeley. 2007. Trade-offs between size and energy reserves reflect alternative strategies for optimizing larval survival potential in rockfish. Marine Ecology Progress Series. 344:2657-270.

Abstract:

Reproductive strategies balancing offspring size and offspring number have been well documented in empirical tests of life-history theory. Here we found an additional trade-off between offspring size and offspring condition. Among 5 species of live-bearing rockfishes (Sebastes spp.) from central Californian populations, we observed a negative relationship between larval length at parturition and the size of their oil globule (a triacylglycerol-rich energy reserve). When compared with a variety of performance variables (resistance to starvation, growth, startle-escape performance and routine activity levels), it appears that this trade-off leads to a conflict when trying to optimize survival potential, with differing benefits to each trait. A large oil globule greatly increases resistance to starvation, whereas larger body size is associated with numerous performance benefits likely to synergistically decrease predation-based mortality and increase success at capturing prey (increased startle speeds and distances, as well as more rapid onset of growth and larger size at age). The tradeoff between energy reserves and body size is further reflected in the seasonal patterns of parturition of the 5 species, with larvae having large oil globules and small body size being released in winter, when productivity in the California Current is low but transport is generally onshore, and those with small oil globule reserves and large body size released in late spring, when productivity is high but transport is generally offshore. These 2 apparent reproductive strategies also reflect subgeneric phylogenetic relationships, suggesting a potential lineage-specific basis for the contrast in larval traits. The results highlight the importance of measuring both physical and performance traits of larvae, as well as considering multiple attributes of both, when evaluating progeny quality.

Life history trade-offs; Offspring size; Larval performance traits; Sebastes.

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Follesa, M., D. Cuccu, R. Cannas, A. Sabatini and A. Cau. 2007. Emigration and retention of Palinurus elephas (Fabricius, 1787) in a central western Mediterranean marine protected area. Scientia Marina. 71:279-285.

This study describes the results obtained by applying the Arnason Schwartz multistate mark-recapture model to eight years of data collected in and around a small no-fishing marine protected area (MPA; 4 km2) in the central western Mediterranean. From 1997 to 2004, a total of 4044 specimens of Palinurus elephas (Fabr., 1787) were tagged and 317 recaptured. The most parsimonious model which best explained the data variability was that of a temporally constant rate of apparent survival and movement in each of the two strata. The absence of any temporal influence in the apparent survival rate inside the no-take area suggested that spillover and mortality are constant for each period of the study. The lower apparent survival rate in surrounding zones than inside the MPA (0.26 ± 0.04 (SE) vs 0.94 ± 0.03 (SE)) is presumed to be a function of fishing effort. A continuous movement of P. elephas across the boundary of the small MPA was also tested. This information on retention of lobsters in the MPA contributes to our understanding of the effect of introducing MPAs into a managed commercial fishery system.

multistate models; survival estimation; movements; spiny lobster; central western Mediterranean.

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Follesa, M. C., D. Cuccu, R. Cannas, S. Cabiddu, M. Murenu, A. Sabatini and A. Cau. 2008. Effects of marine reserve protection on spiny lobster (Palinurus elephas Fabr., 1787) in a central western Mediterranean area. Hydrobiologica. 606:63-68.

The contribution that a small restocking area (central western Mediterranean) has made to the Palinurus elephas (Fabr., 1787) population was examined by comparing the abundances recorded inside and outside the area before (1997) and after the establishment of the reserve (1998-2005). From 1998 to 2002 a progressive percentage increase of P. elephas biomass values was recorded both inside the area and in the surrounding zones. The total mean abundance within the reserve (CPUE = 0.23 ± 0.10 kg/50 m/boat) was 7.5 times greater than that for the neighbouring zone (CPUE = 0.03 ± 0.07 kg/50 m/boat). The inter-annual analysis of lobster size inside the area also showed a progressive increase of adults and juveniles. The results highlighted the effectiveness of fishing restrictions in rebuilding the lobsters population and suggest that small MPAs should be set up.

Spiny lobster; Palinurus elephas; Marine reserve area; Central western Mediterranean.

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Forde, S. E. 2002. Modelling the effects of an oil spill on open populations of intertidal invertebrates. Journal of Applied Ecology. 39:595-604.

Abstract:

1. Knowledge of the impact of oil spills on coastal communities, in California and elsewhere, is currently limited by a lack of long-term data, the inability to infer causality from monitoring studies, and the necessarily limited spatial and temporal scales of experimental studies.
2. This study therefore used a modelling approach to investigate the combined effects of different intensities of an oil spill and recruitment variation on a barnacle Chthamalus fissus population. The methodology and results are likely to apply to any similarly open marine populations with dispersive larval forms.
3. The model consisted of a source population comprising individuals that reproduced based on size and probability of mortality. Larvae from the source population entered a larval pool. A proportion of the larvae from the larval pool recruited to a focal population within the region.
4. The model was used to assess the effects on recruitment to the focal population of (i) the size structure of the source population, (ii) the intensity of oil spills in the source population, and (iii) recruitment intensity to the focal population.
5. Differences in the size structure of the source population had little effect on the reproductive output of the population relative to the intensity of the oil spill. Similarly, the intensity of the oil spill had a stronger influence on recruitment to the focal population than the size structure of the source population. Size structure of the source population was important, however, when evaluating the seasonal trajectory of the focal population.
6. Modelling provides a format in which questions about the effects of human impacts can be addressed that would be intractable using experiments. The results of this model suggest that recruitment variation, along with the processes underlying recruitment variation, are critical to predicting the effects of disturbance on open marine populations.

Barnacle; Chthamalus fissus; disturbance; individual-based model; life history; population model; rocky intertidal.

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Francis, R. C., M. A. Hixon, M. E. Clarke, S. A. Murawski and S. Ralston. 2007. Ten commandments for ecosystem-based fisheries scientists. Fisheries. 32:217-233.

Abstract:

In an effort to accelerate the ongoing paradigm shift in fisheries science from the traditional single-species mindset toward more ecosystem-based approaches, we offer the following “commandments” as action items for bridging the gap between general principles and specific methodologies.

1. Keep a perspective that is holistic, risk-averse, and adaptive.
2. Question key assumptions, no matter how basic.
3. Maintain old-growth age structure in fish populations.
4. Characterize and maintain the natural spatial structure of fi sh stocks.
5. Characterize and maintain viable fish habitats.
6. Characterize and maintain ecosystem resilience.
7. Identify and maintain critical food web connections.
8. Account for ecosystem change through time.
9. Account for evolutionary change caused by fishing.
10. Implement an approach that is integrated, interdisciplinary, and inclusive.

Although the shift in worldview embodied in these commandments can occur immediately without additional funding, full implementation of ecosystem-based fisheries science will require an expanded empirical basis as well as novel approaches to modeling. We believe that pursuing these action items is essential for productive marine fisheries to become truly sustainable for present and future generations.

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Frank, K.T., N.L. Shackell, and J.E. Simon. 2000. An evaluation of the Emerald/Western Bank juvenile haddock closed area. ICES Journal of Marine Science. 57: 1023-1034.

Abstract:

A juvenile haddock (Melanogrammus aeglefinus) closed area was established on the offshore banks (Emerald and Western) of the central Scotian Shelf (NAFO Div. 4W) in 1987. The management objective associated with this meausre was to protect incoming recruits and thereby allow the stock to rebuild. Our evaluation of the effectiveness of the closed area revealed that the management objective was not fully met. The expected trend of declining juvenile mortality after, and high mortality preceding its imposition, was not readily apparent. The lack of response may have been due to several factors: (i) the proportion of juveniles within the closed area steadily declined and a majority of year classes during the post-closure period remained unprotected; (ii) the closed area remained open to fishing by fixed gear whose catches inside the closed area and surrounding areas steadily increased; and (iii) the resident haddock stock deteriorated in terms of growth and condition due to a combination of historical over-exploitation and large-scale environmental changes. The closed area does appear to have had some benefit to other groundfish species in terms of increased abundance, notably American plaice (Hippoglossoides americanus) and winter flounder (Pseudopleuronectes americanus).

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Fraschetti, S., A. Terlizzi, F. Micheli, L. Benedetti-Cecchi and F. Boero. 2002. Marine protected areas in the Mediterranean Sea: Objectives, effectiveness and monitoring. Marine Ecology. 23:190-200.

Abstract:

The number of Marine Protected Areas (MPAs) is continuously increasing worldwide because of the increasing recognition of the profound effects that humans can have on marine systems. A large body of literature deals with marine reserves and their potential as conservation and management tools. In several cases, empirical evidence demonstrated that reserves can harbour greater diversity, higher abundance, and larger organisms than unprotected areas. In most cases, however, reserve design and site selection involved little scientific justification, with no direct test of most of the mechanisms assumed to work in a marine reserve. Field investigations of subtidal marine reserves are generally confounded by intrinsic ecological differences between sites investigated inside and outside reserves, by a lack of site and reserve replication, or by the absence of information about the biota before reserve establishment. This is particularly true in the Mediterranean Sea. The aim of this paper is to show that, at least in the Mediterranean basin, the effectiveness of MPAs has been rarely demonstrated because of lack of appropriate sampling designs. An MPA can be considered as a zone subjected to human impact, presumably a positive one. As a consequence, we propose the use of experimental procedures generally utilised for detecting environmental impacts.

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Froeschke, J. T., L. G. Allen and D. J. Pondella II. 2006. The Fish Assemblages Inside and Outside of a Temperate Marine Reserve in Southern California. Bulletin, Southern California Academy of Sciences. 105:128-142.

The purpose of this investigation was to evaluate the effect of a small marine reserve (established 1988) on a temperate rocky reef fish assemblage at Santa Catalina Island, California. Fish surveys on SCUBA were conducted at two reserve and two non-reserve sites from October 2002 to Janua