Bimini reference

Bimini's endemic and threatened species

What is endemic to Bimini, what is threatened in its waters, and what the law actually says.

This page is a reference summary with its sources attached. Conservation statuses are quoted from the IUCN Red List assessment that carries them, with the assessors, the year and the assessment identifier, because a bare category with no assessment behind it is not checkable. Legal statements are quoted from the gazetted regulation. Where we could not establish something, the page says so rather than rounding it off.

The Bimini boa

Chilabothrus strigilatus fosteri (Barbour, 1941) is the only taxon we could document from a taxonomic authority as endemic to Bimini. It was described from North Bimini — the holotype is MCZ 46054 in the Museum of Comparative Zoology — and named for Richard W. Foster, the amateur malacologist who collected it. The Reptile Database gives its distribution as Bimini and nowhere else.

The name has moved twice, which is why older sources look different. The animal was long treated as Epicrates striatus fosteri, a subspecies of the Hispaniolan boa. Reynolds and colleagues, in a molecular phylogeny of West Indian boas published in 2013, moved the group to the genus Chilabothrus and recognised the Bahamian animals as a separate species,C. strigilatus. Four other subspecies are recognised: ailurus on Cat Island and Alligator Cay, fowleri on Andros and the Berry Islands, mccraniei on Ragged Island, and the nominate strigilatus on New Providence, Eleuthera, Long Island and the Exumas.

Two details worth carrying. The Reptile Database records the 2013 treatment of the Bimini animals as “Chilabothrus strigilatus cf. fosteri”, and the “cf.” is not decoration — it signals that the position of the Bimini population within the species was not fully resolved by that study. And the split is not universally followed: the Reptile Database notes that some authors have continued to treatstrigilatus as a synonym of Epicrates striatus, citing Wallach and colleagues in 2014. A source using the older name is not necessarily out of date by mistake.

Status, and why the headline category misleads

The IUCN Red List assesses Chilabothrus strigilatus as Least Concern (Reynolds and Buckner, 2019; assessment e.T74872197A74874898). There is no IUCN assessment of the Bimini subspecies, because the Red List assesses species rather than subspecies in most cases.

That gap is the single most important thing to understand about this animal. A Least Concern species can contain a subspecies whose entire world range is one small island group. Range size is what makes an island endemic fragile, and it is independent of how the parent species is doing across the rest of its range:

• The whole population is inside one landmass, so a single hurricane, road scheme, fire or clearance programme reaches all of it at once.
• There is no rescue effect. Nothing can recolonise Bimini from a neighbouring population, because there is no neighbouring population of this subspecies.
• North Bimini has been under intensive resort construction since the late 1990s. The peer-reviewed record of that development is about the marine side of it (see below), but the land clearance is the same event.

We found no published population estimate, no trend estimate and no subspecies-level assessment for the Bimini boa. Anyone stating a number for how many are left is not working from a source we could locate.

The smalltooth sawfish

Pristis pectinata Latham, 1794 is a ray, not a shark, despite the shark-like body: like all rays its gills and mouth are on its underside. It takes its name from the rostrum, a long flattened snout edged with 22 to 29 teeth on each side, which it swings through schooling fish to stun them and which also carries an electro-sensory array for detecting prey.

The IUCN Red List assesses it as Critically Endangered (Carlson and others, 2022; assessment e.T18175A249881355). It is among the most imperilled marine fishes in the world, and the reasons are structural rather than incidental. Dulvy and colleagues, reviewing the global status of the family in 2016, found that all five sawfish species are highly threatened; that the toothed rostrum makes them catchable in almost any net; that their fins are among the most valuable in the shark fin trade and their rostra have long been sold as curios; and that they live in shallow coastal water, estuaries and rivers, habitat that overlaps precisely with mangrove loss and coastal development. Historically distributed across the coastal waters of 90 countries and territories, sawfishes are now entirely absent from 20 of them. The smalltooth sawfish specifically is now found in less than 20 per cent of its former range.

NOAA Fisheries lists the U.S. distinct population segment as endangered under the Endangered Species Act — a 2003 listing that made it the first marine fish to receive U.S. federal protection — and the non-U.S. population segment as endangered from 2014. The species is on Appendix I of CITES, Annex II of the SPAW Protocol for the Wider Caribbean, and Appendix I of the Convention on Migratory Species.

The Bahamian situation, and Bimini specifically

NOAA states that outside U.S. waters the species is confirmed to live in The Bahamas. The detail behind that comes from Guttridge and colleagues, writing in theJournal of Fish Biology in 2015 — work in which the Bimini Biological Field Station was directly involved. Their findings for the period 2002 to 2015:

• Only 61 encounters were recorded in the whole of The Bahamas across those thirteen years: 30 at Andros, 19 at Bimini, and 12 across other islands.
• Every Bimini animal exceeded 225 cm stretched total length, which the authors read as indicating that Bimini is not used as a nursery area.
• Andros animals ranged from about 80 to 450 cm, indicating that Andros may be an important nursery and breeding habitat.
• Tracked animals at both islands stayed in less than 3 m of water, frequently alongside mangroves, with residency of 42 days at Bimini and 180 days at Andros.

The paper concludes that The Bahamas is important habitat for the species and stresses the urgent need for national protection and management of the population. That call is still worth reading against the section below: the 2011 shark regulations, comprehensive as they are, are about sharks.

The lemon shark nursery

Negaprion brevirostris (Poey, 1868) is assessed by the IUCN Red List asVulnerable (Carlson and others, 2021; assessment e.T39380A2915472). Bimini’s mangrove-fringed shallows carry one of the longest continuously monitored shark nurseries on record, and the reason is institutional: the Bimini Biological Field Station Foundation, universally called the Shark Lab, was established on South Bimini in 1990 by Dr Samuel Gruber and has run since.

That continuity produced a result that could not have come from a short project. Feldheim and colleagues, publishing in Molecular Ecology in 2014, genetically profiled 20 consecutive cohorts of lemon sharks at Bimini, covering 1993 to 2012. At least six females born in the 1993–1997 cohorts returned to the same site to give birth 14 to 17 years later. That was the first direct evidence of natal philopatry in any cartilaginous fish: females returning to their own birthplace to pup.

The conservation consequence is direct. If females return to the specific place they were born, nursery sites are not interchangeable. Losing one does not displace the animals that used it; it removes the lineage that used it.

What the development did, as measured

North Bimini’s North Sound has been subject to intermittent dredging since 1999 in connection with a large resort development, most intensively in March 2001. Jennings and colleagues tested the effect in 2008 using a before-after, control-impact design, comparing the North Sound with the Sharkland and South Bimini nurseries:

• Growth rates showed no statistically significant difference across the three nurseries before and after March 2001.
• Juvenile survival in the North Sound fell significantly after March 2001, including a23.5 per cent decline in first-year survival.
• Mean percentage cover of turtle grass (Thalassia testudinum) in the North Sound fell by 17.7 per cent between 2003 and 2005.

The authors describe this as a correlation between the development so far and the decline, and call for further work rather than claiming a closed case. Travé and Sheaves surveyed both main nursery grounds in 2010 and published the result in 2014 as a baseline: the ecosystem still appeared in reasonably healthy condition, with some concerning trends.

Bimini is also known for a winter aggregation of great hammerhead,Sphyrna mokarran, assessed by the IUCN Red List as Critically Endangered (Rigby and others, 2019; assessment e.T39386A2920499). We hold only secondary sources for the months of that aggregation, so no season is stated here.

What Bahamian law protects

Two limits on that protection are worth stating plainly. Sawfish are rays, and regulation 36A is written in terms of sharks; we found no sawfish-specific provision anywhere in the consolidated regulations, which is the gap the 2015 Journal of Fish Biology paper was pointing at when it called for national protection.

Separately, the flats species carry their own regime. The 2017 flats fishing regulations make bonefish, permit and tarpon catch-and-release only on the flats, ban commercial flats fishing, and require an angler licence. Those rules and the seasons are set out per species across the fishing section.

What we could not establish

• Any population figure for the Bimini boa. No estimate, no trend, no subspecies-level IUCN assessment.
• Its current legal protection. See the callout above. The Schedule of Ch. 248 as published does not list snakes; the Minister may amend it by order and we could not check for a later order.
• Whether sawfish still use Bimini regularly. The encounter record we relied on runs to 2015. Encounters were rare then and we have no later systematic dataset.
• A complete inventory of Bimini endemics. We did not attempt one. Plants and invertebrates are outside what we checked, and the boa is the endemic vertebrate we could document from a taxonomic authority.
• The months of the great hammerhead aggregation. Secondary sources only.
• Post-2010 condition of the North Sound nursery. The most recent survey we found is Travé and Sheaves’ 2010 fieldwork.

Facts on this page were last checked against the sources below on 12 August 2026.