Photo 2. Caves like this one on Long Island can contain thousands of bats, an irresistible resource for agile predators like boas. Photo: Ali Ball.

Much more after the jump……

This isn’t the first time Caribbean boas (Chilabothrus spp.) have been documented hanging around bat caves to pick off a few bats. A cave in Puerto Rico is a well-known place to observe Puerto Rican boas (Chilabothrus inornatus) draped across the entrances of caves (Photo 2) and grabbing bats out of thin air as they depart for the evening (Link to story).

Photo 3. Puerto Rican boas (C. inornatus) snatching bats from the mouth of a cave in PR. Look closely and you’ll see one of them striking at a flying bat. Photo: Nathan Dappan, Days Edge Productions.

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Now, a brief overview of the Bahamain boas

There are many kinds of boas in the Bahamas, at present, 3 species and several subspecies are found throughout the Bahamas archipelago. However, all species have distinct ranges that can aid in identifying them. All of these beautiful snakes are special parts of the Bahamas ecosystem, and several are only found in the Bahamas. None of these snakes are venomous, and I have handled many without ever getting bit.

Below are a few bits of information on this diverse group of interesting snakes that I hope will help raise awareness of some of The Bahamas most interesting groups, the boas. Another thing to note is that the Genus of Bahamian boas (Caribbean boas in general) was recently changed from Epicrates to Chilabothrus due to recent work by Reynolds et al. (2013; Link).

Photo 4. An adult Chilabothrus exsul from Abaco. Photo: Sean Giery

Abaco boa – Chilabothrus exsul

These feisty little boas (Photo 4) are endemic to the Little Bahama Bank and is the only boa found on Abaco and Grand Bahama. The first photo is of an adult female found near Little Harbour and the second photo is a hatchling, also found near Little Harbour. Hatchlings and young can sometimes be reddish in color, but still have these dark grey blotches over a relatively unpatterned background coloration. Similar to other boas, their diet consists of small mammals and small birds, but the majority of their diet is likely small lizards. They are nocturnally active and spend the day hiding below rocks and logs. Their preferred habitat appears to be coppice habitats and I have seen many of them (alive and dead) right in Marsh Harbour.

Photo 5. Chilabothrus striatus strigilatus from Exuma. This guy looks like he was exploring some of the nooks and crannies in the bedrock to find some food. Photo credit: Ali Ball

Hispaniolan Boa – Chilabothrus striatus

These are large boas (Photo 5), reaching up to 6 feet in length, and can be rather heavy too. C. striates are found among islands of the Great Bahama Bank with several subspecies found on many of the larger islands. Below are the subspecies as long held, however recent research by Reynolds et al. 2013 suggest that some of these groupings are incorrect. In fact, Reynolds suggests that there are at least two species within this group. Unlike the other boas of the Bahamas, C. striatus have complex patterns of diamonds, and angular blotches along their backs. Habitat use varies but these snakes will use forested pinewoods and coppice as well as lightly developed areas. Diet is also likely to be varies including birds, mammals, and other reptiles such as lizards. Perhaps their large size was an adaptation for eating once-abundant rock iguanas? These are the boas that most Bahamians will have seen. They still inhabit New Providence and are often seen on Bimini as well.

New Providence boa (Chilabothrus striatus strigilatus) – New Providence, Eleuthera, Long Island & Exumas

Andros boa (Chilabothrus striatus fowleri) – Andros, Berry Islands

Bimini boa (Chilabothrus striatus fosteri) – Bimini Island

Ragged island boa (Chilabothrus striatus mccraniei) – Ragged Island

Cat Island boa (Chilabothrus striatus ailurus) – Cat Island

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Photo 6. Turks and Caicos Boas (C. chrysogaster) are similar in size and coloration to the Abaco boa. Most are grey with blotches of dark grey along their back. Photo: Graham Reynolds.

Southern Bahamas Boa – Chilabothrus chrysogaster – This small boa (Photo 6), restricted to the Turks and Caicos and southern banks of The Bahamas has been the subject of quite a bit of research over the last few years. Graham Reynolds (Link) sums up much of this research in a 2012 publication (Reynolds and Gerber 2012; Link).  These boas are extensively terrestrial, typically found under rocks during the day. They reach up to about 3 feet in length, but many are less, around 2 feet. Reynolds and Gerber found these snakes to be remarkably abundant in their study, much higher than many other populations of boas in The Bahamas seem to be (~5 per hectare), however, few others have been studied to that extent. The diet of these boas includes eggs and small birds, introduced rodents, and lizards.

Acklin’s boa (Chilabothrus chrysogaster schwartzi) – Acklin’s Boa and Crooked Island

Great Inagua boa (Chilabothrus chrysogaster relicquus) – Great Inagua

Turks and Caicos Boa (Chilabothrus chrysogaster chrysogaster) – Turks and Caicos Islands

Other Resources

Bahamas National Trust: Link

Days Edge Productions: Link

Graham Reynolds: Link

Citations

Reynolds, R.G., M.L. Niemiller, S.B. Hedges, A. Dornburg*, A.R. Puente-Rolón, and L.J. Revell. 2013. Molecular phylogeny and historical biogeography of West Indian boid snakes (Chilabothrus). Molecular Phylogenetics and Evolution 68: 461-470. (Link)

Reynolds, R.G. and G.P. Gerber. 2012. Ecology and conservation of the Turks Island Boa (Epicrates c. chrysogaster: Squamata: Boidae) on Big Ambergris Cay. Journal of Herpetology  46: 578-586. (Link)