23 December 2009

We are now up and running with our first groups of the season at the Blackbird Station. We had a couple of very pleasant snorkels on patch reefs south of the station. There was a focus on fish identification training with a good variety of species noted. Some coral bleaching was noted which included many Montastrea colonies off Calabash Caye as well as on large patches of Agaricia or lettuce coral. Hopefully these colonies will recover with cooler winter water temperatures approaching.

Something that was truly amazing on these snorkels where the abundance of the long spined sea urchin Diadema antillarum. I counted over 700 individuals at these 2 sites which I found mind boggling for there was a pan-Caribbean disease outbreak which wiped out these urchins in the early 1980’s. Further, their loss to the ecosystem has been associated with the regional decline of Caribbean coral reefs since they are considered a very important herbivore which helped prevent macroalgae from overgrowing corals. Seeing these urchins is very encouraging and may signal the local reestablishment of an important herbivore. Further, and perhaps more importantly, it could indicate the huge importance of Turneffe Atoll as a potential natural source of Diadema larvae to replenish other coral reefs in the region.

I am currently writing from Half Moon Caye at the Lighthouse Reef Atoll which is an enchantingly beautiful destination with white sand beaches and nice little upland forest with gumbo limbos and ziricote trees, the latter of which serve as booby nesting sites. We had a great morning snorkel at the famed Blue Hole. Conditions were ideal and we saw a good variety of marine life which included a variety of large parrot fishes, snappers, angel fishes and damselfishes. We also watched cleaner shrimp diligently working on an endangered Nassau grouper (~30 cm TL). An abundance of soft corals was noted as well as small pockets of elkhorn and staghorn corals (Acropora spp.); however, no long spined urchins were seen.

On Half Moon, we had a look at the Red Footed Booby and Magnificent Frigatebird colonies where there was a great vantage point from an observation platform. The male Frigates were displaying their courtship rituals which included inflating their red-colored throat pouches called "gular pouches" and at times sword fighting with their long beaks. We snorkeled of the eastern tip of the caye and saw lots of marine life as well as a few nurse sharks and another Nassau grouper

Back on Blackbird Caye, we have also been exploring the terrestrial environments in the form of guided nature walks. We have had two sightings of the Common Black Hawk which is a majestic raptor with white banding on its tail feathers. We are trying to determine if this bird is transient or a local resident. This species is known to occur on Caye Caulker and the mainland but as far as I’m aware, there are no previous reports of this raptor on Blackbird Caye. We have also been keeping an eye on the resident American crocodiles in a pond on Oceanic Society property.