21 research outputs found
IPBES Sustainable Use of Wild Species Assessment - Chapter 5. Future scenarios of sustainable use of wild species
No full textChapter 5 of the thematic assessment of the sustainable use of wild species of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.Suggested citation: Gasalla, M. A., Tittensor, D. P., Kok, K., Archer, E., Borokini, I., Halouani, G., Matias, D.M., Mbiba, M., Milner-Gulland, E.J., Pacheco, P., Fabricius, C. and Kieling, D. (2022). Chapter 5: Future scenarios of sustainable use of wild species. In: Thematic Assessment Report on the Sustainable Use of Wild Species of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. Fromentin, J.M., Emery, M., Donaldson, J., Danner, M.C., Hallosserie, A., and Kieling, D. (eds.). IPBES secretariat, Bonn, Germany. https://doi.org/10.5281/zenodo.645192
TRACKING GLOBAL FISHERIES FROM SPACE: PATTERNS, PROBLEMS, AND PROTECTED AREAS
No full textFishing is one of the largest and most widespread ocean uses affecting marine ecosystems and biodiversity. From small-scale coastal vessels to industrialized high-seas fleets, the footprint of modern fisheries extends over much of the global ocean. Nonetheless, we have only limited understanding when, where, and how those fisheries are occurring, especially in remote areas far from shore. This poses a problem for fisheries management efforts and marine conservation measures such as marine protected areas (MPAs), which are being established to meet global conservation targets. Fishing is an important factor influencing the effectiveness of MPAs. It is therefore of vital importance to map and analyze the global footprint of fisheries and better understand its influences on the efficacy of marine conservation measures and fisheries management. I apply a novel satellite-based monitoring tool, the Automatic Identification System (AIS), to analyze behavior and movement patterns of fishing vessels globally in the context of marine conservation. For this I developed methods to automatically analyze fishing effort from AIS data and applied these to analyze patterns of fishing vessel behavior around the globe. These new tools allowed me to describe the global distribution of fisheries at fine spatial and temporal resolution. In some cases, fishing effort accumulated close to the boundaries of MPAs, an indicator of spillover of fish benefiting fishing fleets nearby. Near the Galápagos Marine Reserve, fishing effort within 20 km from the reserve boundary was four times higher than in the surrounding area, and tuna catches were higher and more stable near the reserve boundary as well. Patterns of fishing effort around 12 other large MPAs were shaped predominantly by their proximity to Exclusive Economic Zone and MPA boundaries, showing the major effects of maritime zoning regulations on fishing effort. Furthermore, fishing was increased around older MPAs and those in developing countries. Linking fishing vessel behavior to seafood supply chains, I also documented global patterns and hot spots of transshipment of catch to cargo vessels. Using AIS data I found transshipment particularly important in high seas fisheries, such as tuna longlining, raising concerns about mixing of legal and illegal catches in some of the world’s most widespread and valuable fisheries. Finally, I reviewed the effectiveness of spatial protection for highly migratory fish, which is related to a range of species characteristics (e.g. migration, aggregation and homing behaviors) as well as management features (fleet dynamics and management effectiveness). These results provide deeper insight into the global behavior of fishing vessels and highlight the potential and applicability of AIS vessel tracking data to document fishing and transshipment activities in unprecedented detail. By opening a new window of transparency to remote ocean areas, this work provides a foundation for improved high seas governance and management of marine living resources, especially in waters beyond national jurisdiction
β-diversity of deep-sea holothurians and asteroids along a bathymetric gradient (NE Atlantic)
No full textMeasuring and understanding patterns of ?-diversity remain major challenges in community ecology. Recently, ?-diversity has been shown to consist of 2 distinct components: (1) spatial turnover and (2) species loss leading to nestedness. Both components structure deep-sea macrofaunal assemblages but vary in importance among taxa and ocean basins and with energy availability. Here, we present the first evidence for turnover and nestedness along a bathymetric gradient in 2 major megafaunal taxa, holothurians and asteroids. Turnover is the dominant component of ?-diversity throughout bathyal and abyssal zones in both taxa, despite major differences in ?-diversity and trophic composition. High spatial turnover suggests a role for evolutionary adaptation to environmental circumstances within depth bands. This pattern differs fundamentally from those in some macrofaunal groups in low-energy environments where abyssal nestedness is high and diversity low, with diversity maintained partly by source-sink dynamics
Deep, diverse and definitely different: unique attributes of the world's largest ecosystem
No full textThe deep sea, the largest biome on Earth, has a series of characteristics that make this environment both distinct from other marine and land ecosystems and unique for the entire planet. This review describes these patterns and processes, from geological settings to biological processes, biodiversity and biogeographical patterns. It concludes with a brief discussion of current threats from anthropogenic activities to deep-sea habitats and their fauna
Future scenarios of sustainable use of wild species
No full textChanges in economic development, population growth, societal values and demands, as well as environmental and climate change, make the sustainable use of wild species a challenging and dynamic process that requires adaptive management and that will benefit from the use of scenarios
Predicting global habitat suitability for stony corals on seamounts
No full textAim Globally, species distribution patterns in the deep sea are poorly resolved, with spatial coverage being sparse for most taxa and true absence data missing. Increasing human impacts on deep-sea ecosystems mean that reaching a better understanding of such patterns is becoming more urgent. Cold-water stony corals (Order Scleractinia) form structurally complex habitats (dense thickets or reefs) that can support a diversity of other associated fauna. Despite their widely accepted ecological importance, records of scleractinian corals on seamounts are patchy and simply not available for most of the global ocean. The objective of this paper is to model the global distribution of suitable habitat for stony corals on seamounts. Location Seamounts worldwide. Methods We compiled a database containing all accessible records of scleractinian corals on seamounts. Two modelling approaches developed for presence-only data were used to predict global habitat suitability for seamount scleractinians: maximum entropy modelling (Maxent) and environmental niche factor analysis (ENFA). We generated habitat-suitability maps and used a cross-validation process with a threshold-independent metric to evaluate the performance of the models. Results Both models performed well in cross-validation, although the Maxent method consistently outperformed ENFA. Highly suitable habitat for seamount stony corals was predicted to occur at most modelled depths in the North Atlantic, and in a circumglobal strip in the Southern Hemisphere between 20° and 50° S and shallower than around 1500 m. Seamount summits in most other regions appeared much less likely to provide suitable habitat, except for small near-surface patches. The patterns of habitat suitability largely reflect current biogeographical knowledge. Environmental variables positively associated with high predicted habitat suitability included the aragonite saturation state, and oxygen saturation and concentration. By contrast, low levels of dissolved inorganic carbon, nitrate, phosphate and silicate were associated with high predicted suitability. High correlation among variables made assessing individual drivers difficult. Main conclusions Our models predict environmental conditions likely to play a role in determining large-scale scleractinian coral distributions on seamounts, and provide a baseline scenario on a global scale. These results present a first-order hypothesis that can be tested by further sampling. Given the high vulnerability of cold-water corals to human impacts, such predictions are crucial tools in developing worldwide conservation and management strategies for seamount ecosystems. © 2009 Blackwell Publishing Ltd
Extinctions in ancient and modern seas
No full textIn the coming century, life in the ocean will be confronted with a suite of environmental conditions that have no analog in human history. Thus, there is an urgent need to determine which marine species will adapt and which will go extinct. Here, we review the growing literature on marine extinctions and extinction risk in the fossil, historical, and modern records to compare the patterns, drivers, and biological correlates of marine extinctions at different times in the past. Characterized by markedly different environmental states, some past periods share common features with predicted future scenarios. We highlight how the different records can be integrated to better understand and predict the impact of current and projected future environmental changes on extinction risk in the ocean
Acute effects of removing large fish from a near-pristine coral reef
No full textLarge animals are severely depleted in many ecosystems, yet we are only beginning to understand the ecological implications of their loss. To empirically measure the short-term effects of removing large animals from an ocean ecosystem, we used exclosures to remove large fish from a near-pristine coral reef at Palmyra Atoll, Central Pacific Ocean. We identified a range of effects that followed from the removal of these large fish. These effects were revealed within weeks of their removal. Removing large fish (1) altered the behavior of prey fish; (2) reduced rates of herbivory on certain species of reef algae; (3) had both direct positive (reduced mortality of coral recruits) and indirect negative (through reduced grazing pressure on competitive algae) impacts on recruiting corals; and (4) tended to decrease abundances of small mobile benthic invertebrates. Results of this kind help advance our understanding of the ecological importance of large animals in ecosystems
