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

Spawning-Related Movements of Barred Sand Bass, Paralabrax nebulifer, 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 5 141) were recaptured within a 7 to 35-day period. The maximum recapture distance was 92 km. The average (6 SD) non-spawning season recapture distance from peak spawning season tagging locations was 13 6 8 km, and movement was generally northward. A positive relationship existed between fish size (TL) and migration distance to nonspawning 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 6 15 km. Recaptures in subsequent years showed a high degree of spawning (80%, n 5 135) and non-spawning (73%, n 5 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

Half of Atlantic reef-building corals at elevated risk of extinction due to climate change and other threats.

Atlantic reef-building corals and coral reefs continue to experience extensive decline due to increased stressors related to climate change, disease, pollution, and numerous anthropogenic threats. To understand the impact of ocean warming and reef loss on the estimated extinction risk of shallow water Atlantic reef-building scleractinians and milleporids, all 85 valid species were reassessed under the IUCN Red List Categories and Criteria, updating the previous Red List assessment of Atlantic corals published in 2008. For the present assessment, individual species declines were estimated based on the modeled coral cover loss (1989-2019) and projected onset of annual severe bleaching events (2020-2050) across the Atlantic. Species traits were used to scale species relative vulnerability to the modeled cover declines and forecasted bleaching events. The updated assessments place 45.88 -54.12 of Atlantic shallow water corals at an elevated extinction risk compared to the previous assessments conducted in 2008 (15.19 -40.51 ). However, coral cover loss estimates indicate an improvement in reef coverage compared to the historic time-series used for the 2008 assessments. Based on this, we infer that, although remaining dangerously high, the rate of Atlantic reef coral cover decline has surprisingly slowed in recent decades. However, based on modeled projections of sea-surface temperature that predict the onset of annual severe bleaching events within the next 30 years, we listed 26 (out of 85) species as Critically Endangered in the IUCN Red List. Each of these species had previously been listed under a lower threatened category and this result alone highlights the severe threat future bleaching events pose to coral survival and the reef ecosystems they support

The Conservation Status of Marine Biodiversity of the Pacific Islands of Oceania

The Pacific Islands of Oceania are small islands and atolls occurring over a vast expanse of ocean that are characterized by immense biodiversity and endemism. This project represents a major expansion of the coverage of the Pacific Islands’ marine biodiversity on the IUCN Red List of Threatened Species. The threats to Pacific Island marine biodiversity are many. Results from IUCN Red List initiatives such as this can guide decision-making and conservation prioritization of Pacific Island governments, non-governmental organizations (NGOs) and the private sector. By shaping regional and national policies with these data in mind, priority sites for maintaining marine biodiversity can be identified and conserved

Half of Atlantic reef-building corals at elevated risk of extinction due to climate change and other threats

Atlantic reef-building corals and coral reefs continue to experience extensive decline due to increased stressors related to climate change, disease, pollution, and numerous anthropogenic threats. To understand the impact of ocean warming and reef loss on the estimated extinction risk of shallow water Atlantic reef-building scleractinians and milleporids, all 85 valid species were reassessed under the IUCN Red List Categories and Criteria, updating the previous Red List assessment of Atlantic corals published in 2008. For the present assessment, individual species declines were estimated based on the modeled coral cover loss (1989–2019) and projected onset of annual severe bleaching events (2020–2050) across the Atlantic. Species traits were used to scale species’ relative vulnerability to the modeled cover declines and forecasted bleaching events. The updated assessments place 45.88%–54.12% of Atlantic shallow water corals at an elevated extinction risk compared to the previous assessments conducted in 2008 (15.19%–40.51%). However, coral cover loss estimates indicate an improvement in reef coverage compared to the historic time-series used for the 2008 assessments. Based on this, we infer that, although remaining dangerously high, the rate of Atlantic reef coral cover decline has surprisingly slowed in recent decades. However, based on modeled projections of sea-surface temperature that predict the onset of annual severe bleaching events within the next 30 years, we listed 26 (out of 85) species as Critically Endangered in the IUCN Red List. Each of these species had previously been listed under a lower threatened category and this result alone highlights the severe threat future bleaching events pose to coral survival and the reef ecosystems they support

The first IUCN Red List of cold-water corals highlights global declines

The most well-known species-based conservation tool is the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. The current coverage of species in the Red List is known to under-represent benthic marine species. Cold-water corals (CWCs) are increasingly recognised as key to deep-water biodiversity and integral to protected vulnerable marine ecosystems (VMEs), but no deep-sea coral species were previously included in the Red List. We selected 22 cold-water coral species in the Northeast Atlantic, including 4 reef-forming stony corals and 18 octocorals including sea pens and gorgonians, and completed the first IUCN Red List global assessments for corals inhabiting the deep sea. Most of the species assessed herein are habitat-forming, including those that form coral reefs and marine animal forests such as coral gardens or sea pen fields. We assessed eight species as near threatened, and one species as globally vulnerable: Desmophyllum pertusum. Some of these species are distributed across an entire ocean basin, but the cumulative damage from human impacts have reduced populations by upwards of 30% from recent baselines. In addition, three species are listed as data deficient, and the remaining 10 species are assessed as least concern. All assessments in threatened categories were made using Red List criterion A, based on evidence of past population declines, and the main threats in most cases are related to bottom-contact fishing. We also present five case studies that illustrate the application of the Red List criteria to cold-water corals. Despite technological limitations to establishing baseline populations, documented large-scale declines of widespread species clearly demonstrate the magnitude of threats to deep-sea ecosystems and the need for large-scale conservation measures

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

Half of Atlantic reef-building corals at elevated risk of extinction due to climate change and other threats

Atlantic reef-building corals and coral reefs continue to experience extensive decline due to increased stressors related to climate change, disease, pollution, and numerous anthropogenic threats. To understand the impact of ocean warming and reef loss on the estimated extinction risk of shallow water Atlantic reef-building scleractinians and milleporids, all 85 valid species were reassessed under the IUCN Red List Categories and Criteria, updating the previous Red List assessment of Atlantic corals published in 2008. For the present assessment, individual species declines were estimated based on the modeled coral cover loss (1989–2019) and projected onset of annual severe bleaching events (2020–2050) across the Atlantic. Species traits were used to scale species’ relative vulnerability to the modeled cover declines and forecasted bleaching events. The updated assessments place 45.88%–54.12% of Atlantic shallow water corals at an elevated extinction risk compared to the previous assessments conducted in 2008 (15.19%–40.51%). However, coral cover loss estimates indicate an improvement in reef coverage compared to the historic time-series used for the 2008 assessments. Based on this, we infer that, although remaining dangerously high, the rate of Atlantic reef coral cover decline has surprisingly slowed in recent decades. However, based on modeled projections of sea-surface temperature that predict the onset of annual severe bleaching events within the next 30 years, we listed 26 (out of 85) species as Critically Endangered in the IUCN Red List. Each of these species had previously been listed under a lower threatened category and this result alone highlights the severe threat future bleaching events pose to coral survival and the reef ecosystems they support