**3.3 Analysis of risk of extinction of Caribbean biodiversity**

The Caribbean region includes 35 island territories (17 independent and 18 dependent countries comprising about 700 islands, reefs and cays) and 12 continental bordering countries. The Caribbean population is estimated to be about 42.5 million while the region has over 27+ million stay-over tourists each year. The risk of extinction of its biodiversity is due to several factors. Threats to flora, freshwater and marine biodiversity will be reviewed. These include the actions of waves of people starting from Amerindians who appear to have brought plant and animal species with them but who also lived in harmony with the natural world; through colonial times when great tracts of land were denuded of trees such as pimento (*Pimenta dioica*), logwood (*Haematoxylon campechianum* L), mahogany (*Swietenia mahagoni*) and bitterwood (*Picrasma excelsa*) to establish sugarcane plantations with immense associated damage to native biodiversity (to terrestrial and freshwater habitats) and who also imported new plant species; to the present time where destruction of local biodiversity and importation of new biodiversity has continued [7, 13]. Tourism, though needed, has to be managed to reduce its threat to local biodiversity. More recent 'natural' threats include stronger hurricanes, rising ocean temperatures, drought, unpredictable seasons and rising sea levels. Local anthropogenic threats include increasing population densities in rural and urban areas, agriculture, roads (leading to habitat defragmentation and new settlements) and over-harvesting.

The Caribbean region is one of the world's hottest hot spots, with only just over 10% of its original forest cover remaining [14]. This aggravates the vulnerability of the region to hurricanes and other natural disasters. Of the 187 endemic mammals and birds in the Caribbean, at least 43 have become extinct over the last 500 years. Currently, it is estimated that 755 plants and vertebrate species are at risk of extinction [2]. A Lesser Antilles analysis found that of 263 seed plant taxa unique to these islands, 70% are threatened [15]. Of these endemics, most were found on only 1 (37%), 2 (14%) or 3 (13%) islands while 25% were spread over 5 or more islands.

Globally, freshwater biodiversity accounts for 10% [16] of all documented species, with about 167 freshwater fish occurring within the Caribbean [17]. Freshwater biodiversity is threatened by over-exploitation, water pollution, flow modification, destruction and degradation of habitat and invasion of exotic species [18]. Run-off from freshwater drainage leads to mangrove forests on the coast of Caribbean islands. These forests support more than 2000 species of fish, shellfish, invertebrates, and plants [19]. Suggested solutions to reduce risk of extinction for terrestrial ecosystems include protected areas that are well-managed and joined by 'corridors' of wild forest. Also there should be planned botanical collections (in situ, ex situ and in vitro)—held by farmers, institutions and government—recorded in a database registry. Databases and associated seed banks are needed for conservation of plant genetic material for food and agriculture (PGRFA) and for wild species (especially endemics). This information will help the region to determine species most at risk. Another recommendation is the development of an online, up-to-date, addable and searchable database for all Caribbean organisms—flora, fauna, microbes—and associated traditional knowledge—that is in the control of the Caribbean, for the benefit of its inhabitants. The time to act is now.

Marine biodiversity is also at risk. The Caribbean region is 92% sea and contains the largest concentration of marine species in the Atlantic Ocean [3]. The coastal area includes territorial waters up to 12 nautical miles from shore, some areas of these exclusive economic zones (EEZs) are still in dispute. The marine ecosystems in the Caribbean have three critical transboundary issues: (a) illegal, unreported and unregulated (IUU) fishing, (b) habitat degradation and (c) pollution. These are being exacerbated by climate variability and change. The Association of Marine

**Figure 3.**

*Number of OBIS entries for species found in the Caribbean Sea.*

Laboratories of the Caribbean was established in 1957 to facilitate regional collaboration and now includes 30 labs and over 300 members. Collection of data increased after mass mortality of the formerly ubiquitous sea urchin *Diadema antillarum* in 1983–1984 prompted several monitoring programs [20]. The census of marine life (CoML) became involved with the Caribbean in 2004. All the information gathered over the years has been fed into the Ocean Biogeographic Information System (OBIS), a dynamic, global, 4-dimensional (space and time) digital atlas [21]. Through these efforts, knowledge of marine biodiversity in the Caribbean is coming of age. OBIS has 663,339 records, 11,175 species and 15,659 taxa for the "Caribbean Sea" region (accessed August 02, 2019)—most of these were collected since 1992 (https://mapper.obis.org/?areaid=40012#, **Figure 3**). The most wellknown marine ecosystems in the Caribbean are: coral reefs (26,000 km2 ), seagrass beds (66,000 km2 ), and mangroves (11,560 km2 ). Offshore and deep-sea habitats are slowly being documented as well [21].

In the last 30–40 years, anthropogenic impacts have led to degradation of water and land resources, increased sediment run-off, invertebrate extinction and habitat loss. The coverage of mangroves has decreased by an average of 1% per year since 1980. Coral cover in Jamaica was reduced to 10% by 2016, as a result of the concurrent effects of Hurricane Allen (1980), white band disease, reduced herbivory due to over-fishing and mass mortality of the urchin (*Diadema antillarum*) thus allowing algae overgrowth, and a major bleaching event in 2005 [22, 23]. For the future, here is a sobering thought—with blue biotechnology looking to the oceans for medical value—these marine species might be extinct before we even know they were there!

Incomplete information is still an issue. The known taxa for Caribbean coral reefs have been estimated to be only about 5–10% of total species inhabiting these communities. This hinders investigation into population dynamics and other studies [3]. Other issues highlighted were: heterogeneity of sampling effort, variability in collecting methods, relatively less sampling from off-shore and deep sea sites, under-sampling even of more accessible coastal areas, insufficient expert taxonomists, insufficient information guides, with many new species being discovered yearly, so while research and data collection has continued, marine biodiversity knowledge is still insufficient which hampers planning efforts. Another issue highlighted was that collected specimens remain scattered worldwide, with data largely in unavailable formats and sources with limited and inconsistent effort of some external researchers to make this data available. OBIS, is changing this narrative for the better and should be commended [3].

Yet another issue is marine invasive species that may enter the region via direct and indirect routes, possibly with multiple introductions. Most of these transfers
