Showing posts with label Bocas Island. Show all posts
Showing posts with label Bocas Island. Show all posts

Wednesday, June 15, 2011

Looking For Squamates in the Bocas

Between working in the UWITT Museum and running around Trinidad to find supplies we do occasionally get into the field for some serious collecting and fun. On Tuesday, Stevland Charles, Mike Rutherford, and Josh Traub, and I visited two of the Bocas Islands – Gaspar Grande and Monos  - the major goal was to find more coral snakes from each of the islands. However, snakes are notoriously difficult to find no matter how much ground cover you turn. Keeping that in mind we hoped to at least add some footnotes to the islands’ herpetology, and collect some specimens that could supply tissue for molecular studies. Mike was also interested in adding land snails to the UWITT collection. The Bocas Islands (Bocas del Dragon) lie between Trinidad and Venezuela, in the  “Dragons' Mouth”.
Our first stop was Gaspar Grande, a small island composed mostly of limestone. After exiting the boat and a short hike we were at the opening of a sinkhole that descended into a cave; local people had used this as a dump. Using a rope all of us were soon exploring the sink and collecting land snails for Mike and Gonatodes for Stevland. 
Mike and Josh looking for snails in the sinkhole on Gaspar Grande.
Leaf-nosed bats would occasionally brush us. Out of the hole and walking up the trail Gymnopthalmus and Ameiva were quickly getting out of our way. At the top of the  hill were  several relicts of World War II, anti-aircraft gun emplacements, now covered with graffiti and inhabited by some of the island’s lizards. Despite several hours of looking we collected only Gymnopthalmus, a Gonatodes vittatus, and some snails.
We met the boatman at noon and headed for Monos, just a few minutes away.
Stevland directing the boatman to the landing site.
 Landing on Monos, was a bit tricky, the boatman let us off on a crumbling concrete wall several hundred feet from shore. The required us to scramble over slippery, broken concrete to reach shore. As we approached the beach the volume of plastic litter and other man-made junk was alarming. Stevland had been to this location before, and we walked through the coastal palms in to a more seasonal dry forest to a house. As if he knew where to look - an outhouse- Stevland produced a Hemidactylus palichthus within a minute of arrival. This gecko's presence in the Western Hemisphere is a biogeographical puzzle, all of its close living relatives are in Africa, and it is the only Western Hemisphere Hemidactylus that is endemic. All other Western Hemisphere Hemidactylus are  introduced.  
The gecko, Hemidactylus palichthius.

We walked along a stream bed only to encounter a large bamboo die-off that made following the gully exceptionally difficult. As we got deeper into the forest Plica plica became more obvious and abundant, these arboreal and scansorial tropidurid lizards are quite social and on some of the larger tree trunks 3 or 4 individuals were obvious. 

Josh  with a Plica plica on the tree buttress.

Monos has a large amount of human made garbage washing up on its beaches.

Snakes eluded us until we got out of the gully onto the hillside, within a few minutes a Mastigodryas was spotted, but despite being in contact with the hands of two of us it escaped. As we headed back to the beach Mike spotted a Boa constrictor laid out along a broken palm frond. It was a male, about 1.3 m long and had two blood swollen ticks attached to its head. 

Boa constrictor with ticks.

Boa constrictor after tick removal.
After removing the ticks, and a photo session, we were out of water and it was time to met the boatman for the return trip to Trinidad. Despite the fact that we did not find any Bocas coral snakes, the day was not a total loss.