Recovery Trends in Marine Mammal Populations

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From PLOS ONE comes, Recovery Trends in Marine Mammal Populations. You may download the full-text PDF using the link below. The authors compiled 182 time series datasets for the analysis. They found that formerly depleted populations are recovering, on average.

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Table of Contents

Journal Articles

Securing the benefits: Linking ecology with marine planning policy to examine the potential of a network of Marine Protected Areas to support human wellbeing. Siân E. Rees, Stephen Fletcher, Sarah C. Gall, Laura A. Friedrich, Emma L. Jackson, Lynda D. Rodwell. Marine Policy, Available online 29 October 2013.

Wild fish aggregations around fish farms in the Gulf of Aqaba, Red Sea: implications for fisheries management and conservation. Özgül A, Angel D (2013) Aquacult Environ Interact 4:135-145.

Marine protected areas for deepwater fish populations: an evaluation of their effects in Hawai’i. Dana K. Sackett, Jeffrey C. Drazen, Virginia N. Moriwake, Christopher D. Kelley, Brett D. Schumacher, William F. X. E. Misa. Marine Biology, October 2013, DOI: 10.1007/s00227-013-2347-9.

Cumulative human impacts on marine predators. Sara M. Maxwell, Elliott L. Hazen, Steven J. Bograd, Benjamin S. Halpern, Greg A. Breed, Barry Nickel, Nicole M. Teutschel, Larry B. Crowder, Scott Benson, Peter H. Dutton, Helen Bailey, Michelle A. Kappes, Carey E. Kuhn, Michael J. Weise, Bruce Mate, Scott A. Shaffer, Jason L. Hassrick, Robert W. Henry, Ladd Irvine, Birgitte I. McDonald, Patrick W. Robinson, Barbara A. Block & Daniel P. Costa. Nature Communications 4, Article number: 2688; DOI: 10.1038/ncomms3688.

Multidisciplinary rapid assessment of coastal areas as a tool for the design and management of marine protected areas. Diego Álvarez-Berastegui, José Amengual, Josep Coll, Olga Reñones, Juan Moreno-Navas, Tundi Agardy. Journal for Nature Conservation, Available online 31 October 2013.

Long-term change in coral cover and the effectiveness of marine protected areas in the Philippines: a meta-analysis. Evangeline T. Magdaong, Masahiko Fujii, Hiroya Yamano, Wilfredo Y. Licuanan, Aileen Maypa, Wilfredo L. Campos, Angel C. Alcala, Alan T. White, Dean Apistar, Rafael Martinez. Hydrobiologia, October 2013; DOI: 10.1007/s10750-013-1720-5.

From principles to practice: a spatial approach to systematic conservation planning in the deep sea. L. M. Wedding, A. M. Friedlander, J. N. Kittinger, L. Watling, S. D. Gaines, M. Bennett, S. M. Hardy and C. R. Smith. Proc. R. Soc. B 22 December 2013 vol. 280 no. 1773 20131684.

Free: Recovery Trends in Marine Mammal Populations. Magera AM, Mills Flemming JE, Kaschner K, Christensen LB, Lotze HK (2013) PLoS ONE 8(10): e77908. doi:10.1371/journal.pone.0077908.

Free: Additive Partitioning of Coral Reef Fish Diversity across Hierarchical Spatial Scales throughout the Caribbean. Francisco-Ramos V, Arias-González JE (2013) PLoS ONE 8(10): e78761. doi:10.1371/journal.pone.0078761.


Free: Marine Natural Heritage and the World Heritage List: Interpretation of World Heritage criteria in marine systems, analysis of biogeographic representation of sites, and a roadmap for addressing gaps. Abdulla, A., Obura, D., Bertzky, B. and Shi, Y. (2013). IUCN, Gland, Switzerland. xii + 52pp.


Free: Marine Protected Areas, Co-Management and Livelihoods: Coastal Change in Vietnam. Paula Brown. PhD Dissertation, University of Sydney, 2013.

Securing the benefits: Linking ecology with marine planning policy to examine the potential of a network of Marine Protected Areas to support human wellbeing

In line with international commitments to secure human wellbeing via conservation, many nations have set deadlines to implement ecologically coherent networks of Marine Protected Areas (MPAs). However, progress towards achieving these targets is slow. To influence the discourse on the societal need for MPA networks a matrix approach is used to determine the potential for conservation features within the UK proposed network of 127 MPAs to deliver beneficial ecosystem processes and services. The results suggest a non-uniform distribution of ecosystem services across the network, with the majority of MPAs containing conservation features with the potential to deliver ecosystem processes. Designation of the full recommended network of MPAs may provide a form of ecological insurance against further decline in the delivery of beneficial ecosystem services and may also contribute to wider ecological health by supporting broadscale ecological processes. Non designation of MPAs that contain low frequency of occurrence beneficial ecosystem processes or services could result in their loss. Given the uncertainty about the connections between ecological function and the delivery of beneficial ecosystem processes, conservation policy and management must consider an ecologically coherent MPA network to be a minimum spatial requirement to secure the future delivery of ecosystem services.

Wild fish aggregations around fish farms in the Gulf of Aqaba, Red Sea: implications for fisheries management and conservation

Fish farm structures attract a variety of fish species by providing solid structure, and ‘free meals’ in the form of uneaten feed and feces that fall from the cages. In this study, we compared the composition and abundances of wild fish populations around 2 fish farms in the Red Sea and at nearby reference locations. Fish assemblages were evaluated by SCUBA divers carrying out rapid visual censuses in August, September and October 2007. A total of 87238 fishes, representing 39 species and 25 families and a number of trophic levels, were observed. Overall, the abundance, biomass, and diversity of wild fish were much greater at the sea cages than at the open-water reference sites, at both fish farms. It is noteworthy that 35 out of the 39 species observed at the farms were juveniles and adults of coral-reef fish species. This finding is especially interesting, considering that the nearest coral reefs were >4 km away and reef fishes generally have small home ranges, typically <1 km. Among these, the Carangidae (5 species), Sparidae (3 species), and Pomacentridae (3 species) contributed the most to species richness. In light of strong fishing pressures in many areas, the large populations of wild fishes at the fish farms, the high availability of nourishment from artificial food pellets, and restrictions on fishing within farm lease areas, we suggest that coastal net-cage fish farms may serve as small marine protected areas.

Marine protected areas for deepwater fish populations: an evaluation of their effects in Hawai’i

The success of marine protected areas (MPAs) as a tool for conservation and fisheries management has been well documented. However, these results have typically been seen in shallow water systems and questions remain whether this management strategy could be successfully applied to deepwater ecosystems. Our objectives were to determine the efficacy of four deepwater MPAs called bottomfish restricted fishing areas (BRFAs), with various time spans of protection, monitored at depths between 90 and 310 m from 2007 to 2011 for six species of deepwater snapper and one grouper harvested in the Main Hawaiian Islands. Our results suggested that the duration of protection influenced reserve effects, particularly for target species. Mean fish length, and in some cases abundance, increased for one or more of the most economically important target species inside nearly all tested BRFAs. In addition, more mature fish were seen inside the BRFA with the longest duration of protection (~14 years); species richness increased outside this area while inside it remained the same. Here, we provide the first evidence that deepwater MPAs can have positive effects on deepwater species and that many protection effects were consistent with results found in shallow water ecosystems. While these findings are novel, additional data over greater temporal scales will be necessary to determine whether these trends will continue and if others will become important over time.

Cumulative human impacts on marine predators

Stressors associated with human activities interact in complex ways to affect marine ecosystems, yet we lack spatially explicit assessments of cumulative impacts on ecologically and economically key components such as marine predators. Here we develop a metric of cumulative utilization and impact (CUI) on marine predators by combining electronic tracking data of eight protected predator species (n=685 individuals) in the California Current Ecosystem with data on 24 anthropogenic stressors. We show significant variation in CUI with some of the highest impacts within US National Marine Sanctuaries. High variation in underlying species and cumulative impact distributions means that neither alone is sufficient for effective spatial management. Instead, comprehensive management approaches accounting for both cumulative human impacts and trade-offs among multiple stressors must be applied in planning the use of marine resources.

Multidisciplinary rapid assessment of coastal areas as a tool for the design and management of marine protected areas

A method is described for rapid multidisciplinary environmental assessment of coastal areas within the conceptual framework of comprehensive management of Marine Protected Areas (MPAs). The aim is to provide tools for the selection, design and management of coastal MPAs when time, budget or potential human pressures, either alone or in combination, create an urgent need for prioritisation. Maximising results and minimising cost and time is the goal, using a methodology that re evaluates existing information on the area, allows use of physical, environmental and socio-economic indicators, and finally integrates information in a Geographic Information System capable of generating outputs in the form of thematic maps to support managers.

The final products obtained inform planners and managers about the study areas, across multiple aspects that all need to be considered in integrated coastal management. Although originally proposed for widespread use in the Mediterranean, this methodology can be flexibly adapted, with minor modifications in the selection of indicators, for its use in other regions. The results show its potential for merging and synthesising information not only as a tool in Rapid Assessment Programs but also as a tool for facing management of wide coastal areas as social-ecological ecosystems.

Long-term change in coral cover and the effectiveness of marine protected areas in the Philippines: a meta-analysis

Although coral declines have been reported from major reefs of the world, region-specific trends still remain unclear, particularly in areas with high diversity such as the Philippines. We assessed the temporal patterns of the magnitude and trajectory of coral cover change in the Philippines using survey data collected from 317 sites. We examined the rate of change in coral cover in relation to time, effects of bleaching and protection against fishing and assessed the efficacy of marine protected areas (MPAs) using meta-analysis. Results showed an overall increase in coral cover in the Philippines from 1981 to 2010. Protection from fishing contributed to the overall increase in the mean annual rate of change as the coral cover significantly increased within MPAs than outside. The significant differences in the rate of coral cover change through time were influenced by chronic anthropogenic stresses, coinciding with the timing of thermal stress and the establishment of MPAs. The rate of change in coral cover was independent of the level of protection and the age and size of MPA.

From principles to practice: a spatial approach to systematic conservation planning in the deep sea

Increases in the demand and price for industrial metals, combined with advances in technological capabilities have now made deep-sea mining more feasible and economically viable. In order to balance economic interests with the conservation of abyssal plain ecosystems, it is becoming increasingly important to develop a systematic approach to spatial management and zoning of the deep sea. Here, we describe an expert-driven systematic conservation planning process applied to inform science-based recommendations to the International Seabed Authority for a system of deep-sea marine protected areas (MPAs) to safeguard biodiversity and ecosystem function in an abyssal Pacific region targeted for nodule mining (e.g. the Clarion–Clipperton fracture zone, CCZ). Our use of geospatial analysis and expert opinion in forming the recommendations allowed us to stratify the proposed network by biophysical gradients, maximize the number of biologically unique seamounts within each subregion, and minimize socioeconomic impacts. The resulting proposal for an MPA network (nine replicate 400 × 400 km MPAs) covers 24% (1 440 000 km2) of the total CCZ planning region and serves as example of swift and pre-emptive conservation planning across an unprecedented area in the deep sea. As pressure from resource extraction increases in the future, the scientific guiding principles outlined in this research can serve as a basis for collaborative international approaches to ocean management.

Recovery Trends in Marine Mammal Populations

Marine mammals have greatly benefitted from a shift from resource exploitation towards conservation. Often lauded as symbols of conservation success, some marine mammal populations have shown remarkable recoveries after severe depletions. Others have remained at low abundance levels, continued to decline, or become extinct or extirpated. Here we provide a quantitative assessment of (1) publicly available population-level abundance data for marine mammals worldwide, (2) abundance trends and recovery status, and (3) historic population decline and recent recovery. We compiled 182 population abundance time series for 47 species and identified major data gaps. In order to compare across the largest possible set of time series with varying data quality, quantity and frequency, we considered an increase in population abundance as evidence of recovery. Using robust log-linear regression over three generations, we were able to classify abundance trends for 92 spatially non-overlapping populations as Significantly Increasing (42%), Significantly Decreasing (10%), Non-Significant Change (28%) and Unknown (20%). Our results were comparable to IUCN classifications for equivalent species. Among different groupings, pinnipeds and other marine mammals (sirenians, polar bears and otters) showed the highest proportion of recovering populations, likely benefiting from relatively fast life histories and nearshore habitats that provided visibility and protective management measures. Recovery was less frequent among cetaceans, but more common in coastal than offshore populations. For marine mammals with available historical abundance estimates (n = 47), larger historical population declines were associated with low or variable recent recoveries so far. Overall, our results show that many formerly depleted marine mammal populations are recovering. However, data-deficient populations and those with decreasing and non-significant trends require attention. In particular, increased study of populations with major data gaps, including offshore small cetaceans, cryptic species, and marine mammals in low latitudes and developing nations, is needed to better understand the status of marine mammal populations worldwide.

Additive Partitioning of Coral Reef Fish Diversity across Hierarchical Spatial Scales throughout the Caribbean

There is an increasing need to examine regional patterns of diversity in coral-reef systems since their biodiversity is declining globally. In this sense, additive partitioning might be useful since it quantifies the contribution of alpha and beta to total diversity across different scales. We applied this approach using an unbalanced design across four hierarchical scales (80 sites, 22 subregions, six ecoregions, and the Caribbean basin). Reef-fish species were compiled from the Reef Environmental Education Foundation (REEF) database and distributions were confirmed with published data. Permutation tests were used to compare observed values to those expected by chance. The primary objective was to identify patterns of reef-fish diversity across multiple spatial scales under different scenarios, examining factors such as fisheries and demographic connectivity. Total diversity at the Caribbean scale was attributed to β-diversity (nearly 62% of the species), with the highest β-diversity at the site scale. α¯¯-diversity was higher than expected by chance in all scenarios and at all studied scales. This suggests that fish assemblages are more homogenous than expected, particularly at the ecoregion scale. Within each ecoregion, diversity was mainly attributed to alpha, except for the Southern ecoregion where there was a greater difference in species among sites. β-components were lower than expected in all ecoregions, indicating that fishes within each ecoregion are a subsample of the same species pool. The scenario involving the effects of fisheries showed a shift in dominance for β-diversity from regions to subregions, with no major changes to the diversity patterns. In contrast, demographic connectivity partially explained the diversity pattern. β-components were low within connectivity regions and higher than expected by chance when comparing between them. Our results highlight the importance of ecoregions as a spatial scale to conserve local and regional coral reef-fish diversity.

Marine Natural Heritage and the World Heritage List: Interpretation of World Heritage criteria in marine systems, analysis of biogeographic representation of sites, and a roadmap for addressing gaps

A new IUCN report identifying gaps in marine World Heritage was launched today at the 3rd International Marine Protected Areas Congress (IMPAC). The study provides a road map to ensure the World Heritage Convention reflects the diversity of marine ecosystems in future nominations.

The World Heritage List includes a relatively small number of sites explicitly recognized for their outstanding universal marine values. Today, it counts 46 marine sites spanning across 35 countries.

This represents about 20% of the natural World Heritage and less than 5% of the total World Heritage. Yet oceans and seas make up over 70% of Earth’s surface and 95% of its habitable space.

Strikingly, less than 3% of the world’s oceans and under 0.2% of high seas are currently protected. World Heritage covers about a quarter of this area.

Marine World Heritage features mainly tropical ecosystems; as a consequence temperate and polar ecosystems are underrepresented.

Over three quarters of the planet’s nearshore areas (under 200 meters deep) either include no World Heritage at all or contain sites with just 1% marine coverage. Likewise, a large proportion of deep-sea habitats do not have any World Heritage sites.

This means the full range of irreplaceable values in these marine ecosystems are bypassed. For example, there are no marine World Heritage sites in the Antarctic, Gulf Stream, Sunda Shelf or Andaman.

One challenge to applying World Heritage to the marine environment to date has been the lack of a clear definition for marine features of potential outstanding universal values.

To overcome this, the study proposes 16 themes, including for example ocean currents, ice, seamounts or diversity of marine life, that can help identify, nominate and inscribe sites representing the most outstanding examples.

This is part of a wider analysis of the approaches that can be adopted to fill marine heritage gaps. The study encourages further regional and global analyses to identify priority areas for potential inclusion on the World Heritage List.

“The World Heritage Convention needs to address the diversity of the marine realm to ensure it can make a relevant contribution to the challenges that face our planet in the 21st Century,” says Tim Badman, Director of IUCN World Heritage Programme.

“Currently, about 40% of marine sites are coral reefs; a balanced World Heritage List would also need to include other types of ecosystems, such as kelp forests, seamounts, rocky reefs or polar habitats. This study provides better guidance for nations to achieve this.”

Marine Natural Heritage and the World Heritage List is the second IUCN gap analysis, with a first study identifying terrestrial gaps published earlier this year. Their aim is to help build a representative, balanced and credible World Heritage List by providing a scientific framework to inform decisions when nominating and inscribing new sites.

Marine Protected Areas, Co-Management and Livelihoods: Coastal Change in Vietnam

Global marine conservation targets have driven the increase in marine protected area (MPA) programs in recent decades, and international donors and environmental non-government organisations have promoted their expansion to the developing world. Conflicts can result between MPAs and local livelihoods and local resource governance systems, and new livelihoods and resource governance systems introduced through MPA projects. The alternative livelihoods proposed to offset conflicts occur as MPAs and local livelihoods are often based around the assumption that local people are willing and able to give up their existing fishing livelihoods, despite the reality that the “alternative livelihoods” are often not sufficient to replace existing livelihoods The literature on MPA practice often fails to adequately reflect what occurs in practice around livelihoods change, or to propose ways to work within existing livelihoods constraints. Thus a gap exists between results repo rted from MPA projects and what occurs on the ground through MPA implementation. A social research lens is needed to examine what occurs “behind the beautiful curtain” of MPA reporting at the local, regional and national level.

The research presented in this thesis investigates what happens in the implementation of co-management and MPAs as model approaches, how they have been translated to and within the context of Vietnam, and how fishing-based livelihoods are transformed through these processes. The thesis considers “aquarian transitions” in the coastal zone around processes of regulatory, environmental and livelihoods change associated with agrarian change analysis. Aquarian transition re-frames these processes to the specificities of the aquatic context and to the rural coastal landscape of the MPA. The research questions addressed through this thesis are:

  • What are the socio-political influences on MPA management and how do these affect the achievement of biodiversity conservation and sustainable re! source m anagement objectives? How do the institutions of MPA development play out at different scales, from the local to the national? What is the influence of different government, non-government and international actors at these different scales?
  • How does co-management of aquatic natural resources work in Vietnam given its centralized, authoritarian mode of government and the flow-on effects of this on natural resource governance? How are universalistic co-management practices developed and promoted by international actors from the west/global north translated within the context of Vietnam?
  • How do MPAs in Vietnam affect and address existing livelihoods of local people within and around the protected area? Are alternative livelihoods programs successful or adequate? Do they replace or only supplement existing livelihoods? What assumptions are evident within livelihood programs about local people’s adaptation to livelihood change in the face of restricted access?

Multi-sited and multi-scaled ethnography was used in the research to address research questions around livelihoods, co-management, and the institutions of MPA development. This thesis forms an ethnography of development institutions examining both MPA policy and practice in Vietnam.

The research was implemented in Vietnam over 18 months from January 2006 to December 2007, with follow up field work undertaken in mid-2010. The data collected was qualitative, and based on observation and participation in activities with each case study under investigation. Case studies of several kinds were investigated – one NGO-focused case study following one of that NGO’s projects as well as their overall development approach to MPAs (Trao Reef Marine Reserve, with MCD – the Center for Marinelife Conservation and Community Development), one conventional site-based case study of an MPA and its local and regional context (Cu Lao Cham MPA); and one policy developme nt case study of the national livelihoods strategy for the LMPA (Livelihoods support for Marine Protected Areas) program within the national Ministry of Fisheries. The strategy captured the lessons learned in livelihoods management at all MPAs in Vietnam to that time, and implementation of the strategy reflected the debate around livelihoods practice evident during 2007.

I conducted participant observation during training activities at regional case study sites, as well as at sites of policy development in Hanoi and with a range of actors. In the capital my research activities were involved with national government ministries, a case study Vietnamese NGO, and with IUCN who hosted my research in Vietnam through provision of office facilities. In regional locations, participant observation was focussed around the two principal case studies and involved regional training activities for MPA managers, provincial meetings focussed on MPA management, management plan development workshops, as well as training events held with local people by MPA management. The multi-sited nature of this ethnography enabled the study of policy formulation as well as implementation, and the translation processes occurring between the different actors at these sites and scales.

Community-based approaches to MPA management mobilised much greater participation and connection to marine conservation than more traditional government MPA management. The cost of these approaches was the length of time needed to implement them, the limited geographic impact they had on the ground, and the lack of respect for these approaches demonstrated by government representatives. Operation outside of the government context in Vietnam had costs and benefits, in that MCD’s approaches to MPA management were not valued by government, but were valued by international donors who wanted to fund grassroots projects without the hindrance of central and provincial government bureaucracy. Provincial government’s attempts to implement co-management were much more top down, and resulted in participation in MP A activities at the local level without connection to the power structures operating at the regional level above. Past and current MPA practice during this research demonstrated that provincial government struggled with the horizontal connections required to develop collaborative management arrangements across this level of government.

Efforts at MPA enforcement in Vietnam were hampered by a “perfect storm” of non-compliance caused by the effectively open access nature of coastal resources, large numbers of coastal populations and their livelihood needs, and absence of livelihood alternatives. These results are relevant outside of the context of Vietnam as other countries experiencing similar population pressures in coastal zones and fishing livelihood dependence of coastal communities are likely to face similar limitations on the success of enforcement. The fact that alternative livelihoods do not easily work as alternatives needs to be better explored by the literature on MPA practice, as the promotion of the alternative concept can create false expectations about what it can deliver on the ground. MPA projects will have much greater chance of success if they start with more realistic goals around livelihood diversification at the outset.

The research demonstrates how international models are often poorly adapted to fit the local context they are introduced to. In the case of alternative livelihoods implementation or territorialised regulation around subsistence livelihoods, they can be weak in theory from the outset. These model approaches are shown not to work in the local context. The local scale demonstrates the outcome of translation of policy approaches from the international scale and through the national and regional scales of influence, where different actors and processes affect the policy’s form and outcome. What occurs at the local level is a consequence of these processes of translation and adaptation to the local. The multi-sited and multi-scaled ethnography of d! evelopme nt institutions enables these processes to be revealed, and highlights how MPA projects can appear as islands of project activity in a sea of socio-political complexity.

The thesis contributes to the literature on livelihood management in the coastal zone, paying specific attention to alternative livelihoods interventions. It also contributes to the literature on both MPA and fisheries management practice. The findings in these areas will have relevance to any case where livelihood substitution is being considered beyond the focal points of MPAs and Vietnam. It contributes an important critical focus to the use of model approaches to natural resource management, and the role that international donors play in forcing the implementation of these approaches in developing countries. It also contributes to the methodological literature as an example of ethnography of development institutions, of how experience-from-practice may contribute to the greater literature by document ing the experiences and key lessons from development practice.