Extinction risk and conservation of marine bony shorefishes of the Greater Caribbean and Gulf of Mexico

Abstract

Understanding the conservation status of species is important for prioritizing the allocation of resources to redress or reduce biodiversity loss. Regional organizations that manage threats to the marine biodiversity of the Caribbean and Gulf of Mexico seek to delineate conservation priorities. This process can be usefully informed by extinction risk assessments conducted under the International Union for Conservation of Nature (IUCN) Red List criteria: a widely used, objective method to communicate species‐specific conservation needs. Prior to the recent Red List initiatives summarized in this study, the conservation status was known for just one‐quarter of the 1360 Greater Caribbean marine bony shorefishes. During 10 Red List workshops, experts applied data on species' distributions, populations, habitats, and threats in order to assign an extinction risk category to nearly 1000 shorefishes that range in the Greater Caribbean. As conservation is mostly implemented at national and local levels, two more workshops assessed the Gulf of Mexico populations of 940 shorefishes using the regional Red List guidelines. About 5% of these shorefishes are globally or regionally threatened, including 6% of Greater Caribbean endemics and 26% of Gulf endemics. About 9% of the species are Data Deficient. Species‐richness analyses show that the highest numbers of threatened species endemic to the Greater Caribbean are found in Belize, Panama, and the Cayman Islands. The most pervasive threats to the threatened and Near Threatened species are overexploitation, habitat degradation, and predation by the invasive lionfish. Half of the threatened species are experiencing multiple threats that are likely to amplify extinction risk. Recommended actions, in addition to conducting diversity surveys in lesser explored areas, include improving fishery management, reducing habitat degradation, and controlling lionfish populations.

Monitoring Extinction Risk and Threats of the World’s Fishes based on the Sampled Red List Index

“…Overall, the sRLI for marine shes is the highest of the Red List indices calculated so far (bar the historical index estimated for reef-building corals pre-1998 24 ). Our estimate of 4.7% of marine sh threatened with extinction is lower than threat levels found in other studies on extinction risk of marine shes: regional shore shes (5-9.4% 41,46 ), sharks and rays (17.4% 34 ), hag shes (12% 30 ), groupers (12% 33 ), tarpons, lady shes and bone shes (12.5% 35 ), porgies (8.6% 37 ), and puffer shes (7.9% 38 ). But we are not surprised as threat tends to be greatest in shallower waters and a random sample of marine shes will have disproportionately greater deepwater species than the shallowwater taxa that have dominated early assessment priorities.…”

“…Many additional assessments of marine shes have resulted from regional initiatives, further broadening the taxonomic coverage of the Red List 8 . These include nearly all nearshore and many deep sea marine shes from the Mediterranean 39 , Eastern Central Paci c 40 , Western Central Atlantic and Gulf of Mexico 41,42 , Oceania 43 , European waters 44 , Eastern Central Atlantic 45 , and Persian Gulf 46 .…”

Comparing biodiversity databases: Greater Caribbean reef fishes as a case study

“…Due to a long history of intensive exploration of the Greater Caribbean, the shore fishes of the region represent possibly the best known such fauna of any major marine bioregion in the world (Floeter et al, 2008;Linardich et al, 2019;Miloslavich et al, 2010).…”

“…Due to a long history of intensive exploration of the Greater Caribbean, the shore fishes of the region represent possibly the best known such fauna of any major marine bioregion in the world (Floeter et al, 2008; Linardich et al, 2019; Miloslavich et al, 2010). Consequently, the present study could be considered as a “best case scenario” for comparing biodiversity databases and determining the state of the knowledge.…”

Trait‐based vulnerability reveals hotspots of potential impact for a global marine invader

“…Most common Caribbean fishes are widely distributed in the region, and many also range southward to Brazil (Robertson & Cramer, 2014). A histogram of the range sizes of all Greater Caribbean endemic bony shorefishes ( N = 674) with a bin size of 20,000 km 2 revealed that range size is strongly right skewed, with a natural break at 80,000 km 2 (Linardich, 2016). We added a 20,000 km 2 buffer to this natural break in range size, and considered a species to be ‘range‐restricted’ if the area of the distribution polygon was less than 100,000 km 2 .…”