Hotspots, Extinction Risk and Conservation Priorities of Greater Caribbean and Gulf of Mexico Marine Bony Shorefishes

Understanding the status of species is important for allocation of resources to redress biodiversity loss. Regional organizations tasked with managing threats to the 1,360 marine bony shorefishes of the Caribbean and Gulf of Mexico would benefit from a delineation of conservation priorities. However, prior to this study, conservation status was known for only one quarter of these shorefishes. Extinction risk assessment under IUCN Red List Criteria is a widely-used, objective method to communicate species-specific conservation needs. Data were collated on each species’ distribution, population, habitats and threats and experts at three Red List workshops assigned a global level extinction risk category to nearly 1,000 greater Caribbean shorefishes. Since conservation is mostly implemented at a sub-global level, regional Red List assessments for the 940 shorefishes that occur in the Gulf of Mexico were conducted at two additional workshops. As a result, between 4-5% of these shorefishes are globally or regionally listed at a threatened level and 8-9% are Data Deficient. If all DD species are assumed threatened, the total threatened could be as high as 12% and 13%, respectively. The major threats are identified as overexploitation, habitat degradation (especially estuaries and coral reef) and invasive lionfish predation and half of the threatened or Near Threatened species are impacted by multiple threats. Data Deficient species are commonly known from only few records or when impact from a threat is suspected, but poorly understood. Species richness analyses using distribution maps vetted during the Red List process indicate that hotspots of limited range endemics, which are species that may be more susceptible to extinction, are located in Venezuela, Belize and the northeastern Gulf of Mexico. Nearly a quarter of the Gulf endemics are threatened. The regional threat level for Gulf non-endemics is slightly lower than the global threat level. Immediate conservation needs are as follows: improve fishery management, reduce habitat degradation, control lionfish density, implement multiple threat scenario conservation planning and conduct diversity surveys in lesser explored areas. These baseline extinction risk assessments will provide an opportunity to measure conservation progress over time as well as inform future analyses of Key Biodiversity Areas

Spawning-Related Movements of Barred Sand Bass \u3ci\u3eParalabrax nebulifer\u3c/i\u3e, in Southern California: Interpretations from Two Decades of Historical Tag and Recapture Data

During the 1960s and 1990s, the California Department of Fish and Game tagged 8,634 barred sand bass in southern California, and 972 fish (11%) were recaptured. Tag returns suggest barred sand bass are transient aggregate spawners that form spawning aggregations consisting of both resident and migrant individuals. Spawning residency at a historic spawning location was estimated by the frequency of returns over time; most same-year returns (82%, n  =  141) were recaptured within a 7 to 35-day period. The maximum recapture distance was 92 km. The average (± SD) non-spawning season recapture distance from peak spawning season tagging locations was 13 ± 8 km, and movement was generally northward. A positive relationship existed between fish size (TL) and migration distance to non-spawning season recapture locations. Fish tagged at a presumed non-spawning season residence were primarily recaptured south of the tagging location during peak and late spawning season; the average migration distance was 17 ± 15 km. Recaptures in subsequent years showed a high degree of spawning (80%, n  =  135) and non-spawning (73%, n  =  11) site fidelity. This is the first documentation of the spawning-related movements of barred sand bass and will be important for informing management decisions regarding this popular sport fish

Translating Globally Threatened Marine Species Information into Regional Guidance for the Gulf of Mexico

A comprehensive understanding of the status of marine organisms in the Gulf of Mexico is critical to the conservation and improved management of marine biodiversity in the region. Threats and extinction risk, based on application of the IUCN Red List Categories and Criteria at the global level, were analyzed for 1,300 Gulf of Mexico marine species. These species include all known marine mammals, sea birds, marine reptiles, cartilaginous fishes, bony shorefishes, corals, mangroves, seagrasses and complete clades of select invertebrates. Analyses showed that 6% of these species are threatened, 2% Near Threatened, 9% Data Deficient, and 83% Least Concern. However, the majority of these species are not endemic to the Gulf, and therefore are globally impacted by threats that may or may not be particularly intense within the Gulf. For example, many of these species are impacted by fisheries in much of their global range; however, the intensity of fishing pressure varies across their ranges, and some of these exploited species are well managed in the Gulf of Mexico. Other anthropogenic impacts, including industrial development, pollution, and habitat loss also vary in intensity across species\u27 global ranges. Here we provide recommendations for interpreting the application of global IUCN Red List Categories at the subglobal/regional scale, while highlighting conservation measures needed for marine species specific to the Gulf region

A Trait‐Based Framework for Assessing the Vulnerability of Marine Species to Human Impacts

Marine species and ecosystems are widely affected by anthropogenic stressors, ranging from pollution and fishing to climate change. Comprehensive assessments of how species and ecosystems are impacted by anthropogenic stressors are critical for guiding conservation and management investments. Previous global risk or vulnerability assessments have focused on marine habitats, or on limited taxa or specific regions. However, information about the susceptibility of marine species across a range of taxa to different stressors everywhere is required to predict how marine biodiversity will respond to human pressures. We present a novel framework that uses life-history traits to assess species’ vulnerability to a stressor, which we compare across more than 44,000 species from 12 taxonomic groups (classes). Using expert elicitation and literature review, we assessed every combination of each of 42 traits and 22 anthropogenic stressors to calculate each species’ or representative species group’s sensitivity and adaptive capacity to stressors, and then used these assessments to derive their overall relative vulnerability. The stressors with the greatest potential impact were related to biomass removal (e.g., fisheries), pollution, and climate change. The taxa with the highest vulnerabilities across the range of stressors were mollusks, corals, and echinoderms, while elasmobranchs had the highest vulnerability to fishing-related stressors. Traits likely to confer vulnerability to climate change stressors were related to the presence of calcium carbonate structures, and whether a species exists across the interface of marine, terrestrial, and atmospheric realms. Traits likely to confer vulnerability to pollution stressors were related to planktonic state, organism size, and respiration. Such a replicable, broadly applicable method is useful for informing ocean conservation and management decisions at a range of scales, and the framework is amenable to further testing and improvement. Our framework for assessing the vulnerability of marine species is the first critical step toward generating cumulative human impact maps based on comprehensive assessments of species, rather than habitats

Conservation status of marine biodiversity of the Western Indian Ocean

The Western Indian Ocean is comprised of productive and highly diverse marine ecosystems that are rich sources of food security, livelihoods, and natural wonder. The ecological services that species provide are vital to the productivity of these ecosystems and healthy biodiversity is essential for the continued support of economies and local users. The stability of these valuable resources, however, is being eroded by growing threats to marine life from overexploitation, habitat degradation and climate change, all of which are causing serious reductions in marine ecosystem services and the ability of these ecosystems to support human communities. Quantifying the impacts of these threats and understanding the conservation status of the region’s marine biodiversity is a critical step in applying informed management and conservation measures to mitigate loss and retain the ecological value of these systems. This report highlights trends in research needs for species in the region, including priorities for fundamental biological and ecological research and quantifying trends in the populations of species. The assessments and analyses submitted in this report should inform conservation decision-making processes and will be valuable to policymakers, natural resource managers, environmental planners and NGOs

Impacts of salinity and freshwater inflow on oyster-reef communities in Southwest Florida

When assessing oyster-reef habitat in estuaries it is important to understand the influence of salinity on the spatial and temporal variability of associated organisms. How comparable is community structure among stations located at different points along the salinity gradients of estuaries or among tidal tributaries that experience different levels of freshwater inflow? Do assemblages vary seasonally in response to changing salinity and freshwater inflow? To address these questions, multivariate techniques were employed to analyze decapod crustacean and fish abundance data. Organisms were collected at three reefs along the salinity gradient of three estuaries: the Caloosahatchee River and estuary, Estero River and Bay, and Faka Union Canal and Bay. Additional collections were made from reefs located near the mouths of Estero Bay's five tidal tributaries. Samples were dominated by the decapods Eurypanopeus depressus and Petrolisthes armatus. Commonly occurring species included the decapods Panopeus obesus, Alpheus heterochaelis and Rhithropanopeus harrisii and the fishes Gobiosoma robustum, Lophogobius cyprinoides and Gobiesox strumosus. Analysis of similarities suggested differences among stations located along the salinity gradients of all three estuaries. Community structure also varied among stations located near the mouths of the tidal tributaries of Estero Bay. Multidimensional scaling identified community structure present at upper stations as distinct from that downstream and at high-flow tributaries as distinct from that near low-flow tributaries. Upper stations and stations near high-flow tributaries were typified by E. depressus and gobiid fishes. Downstream stations and stations near low-flow tributaries were typified by E. depressus and P. armatus. Percent dissimilarity was greatest when upper and lower stations were compared along the salinity gradient or when low salinity and high-salinity sites were compared among tributaries. Within-station sample variability tended to be higher upstream or in association with high-flow tributaries

Valuable but vulnerable: Over-fishing and under-management continue to threaten groupers so what now?

Among threats to marine species, overfishing has often been highlighted as a major contributor to population declines and yet fishing effort has increased globally over the past decade. This paper discusses the decadal reassessment of groupers (family Epinephelidae), an important and valuable group of marine fishes subjected to high market demand and intense fishing effort, based on IUCN criteria. Allowing for uncertainty in the status of species listed as Data Deficient, 19 species (11.4%) are currently assigned to a “threatened” category. This first reassessment for a large marine fish taxon permits an evaluation of changes following the original assessments, provides a profile of the current conservation condition of species, identifies the challenges of assessing con- servation status, and highlights current and emerging threats. Measures needed to reduce threats and lessons learned from conservation efforts are highlighted. Present threats include intensifying fishing effort in the face of absent or insufficient fishery management or monitoring, growing pressures from international trade, and an inadequate coverage in effectively managed, sized, or located protected areas. Emerging threats involve expansion of fishing effort into deeper waters and more remote locations, shifts to previously non-targeted species, increases in the capture, marketing and use of juveniles, growing demands for domestic and interna- tional trade, and, potentially, climate change. Those species most threatened are larger-bodied, longer-lived groupers, most of which reproduce in spawning aggregations

The status of marine biodiversity in the Eastern Central Atlantic (West and Central Africa)

International audienceThe status of marine biodiversity in the Eastern Central Atlantic (ECA), especially of coastal and pelagic fishes, is of concern owing to a number of threats including overharvesting, habitat loss, pollution, and climate change combined with inadequate policy responses, legislation, and enforcement. This study provides the first comprehensive documentation of the presence, status, and level of extinction risk, based on IUCN Red List assessment methodology, for more than 1800 marine species, including all taxonomically described marine vertebrates (marine mammals, sea turtles, seabirds, fishes); complete clades of selected marine invertebrates (sea cucumbers, cone snails, cephalopods, lobsters, reef-building corals); and marine plants (mangroves, seagrasses). Approximately 8% of all marine species assessed in the ECA are in threatened categories, while 4% are listed as Near Threatened, 73% are Least Concern, and 15% are Data Deficient. Fisheries and overharvesting are the biggest threats to living marine resources in the ECA, with 87% of threatened species across all taxonomic groups affected by both large- and small-scale targeted fisheries, excessive capture as by-catch, or unsustainable harvest. The results of this study will transform the current state of knowledge and increase capacity for regional stakeholders to identify and enact marine conservation and research priorities, as a number of species are identified as having high conservation and/or research priorities in the region. Through the process of marine species data collection and risk assessments conducted over the past 5 years, several key conservation actions and research needs are identified to enable more effective conservation of marine biodiversity in the ECA, including increased governance, multilateral collaboration, taxonomic training, and improved reporting of fisheries catch and effort

Red List of Marine Bony Fishes of the Eastern Central Atlantic.

International audienceThe Red List of Marine Bony Fishes of the Eastern Central Atlantic (ECA) is a review of the conservation status of all native marine bony fishes in ECA according to the global Categories and Criteria of the IUCN Red List of Threatened Species. It identifies those species that are threatened with extinction at the global level and occur within the ECA region. This comprehensive assessment, which is the first of its kind in the ECA, aims to provide improved knowledge of species presence and extinction risk status for the purposes of guiding conservation actions and improved policies for these species both globally and regionally