Quarterly Bulletin of the Trinidad and Tobago Field Naturalists’ Club April – June 2014 Issue No: 2/2014 Saturday 22nd - Sunday 23rd February HUEVOS EXPEDITION 2014 - From Dolphins to Damselfish - A Marine Biologist’s Perspective by Amy Deacon In terms of natural history sightings, the Huevos a pod of bottlenose dolphins, Tursiops truncatus. trip got off to a spectacular start. Minutes after leav- ing Chaguaramas, we found ourselves surrounded by (Continued on page 3) An impressive leap performed by one of the bottlenose dolphins, Tursiops truncatus. Photo sequence captured by: Jeffrey Wong Sang Page 2 THE FIELD NATURALIST Issue No. 2/2014 Inside This Issue HUEVOS EXPEDITION 2014 Quarterly Bulletin of the Saturday 22nd - Sunday 23rd February Trinidad and Tobago Field Naturalists’ Club April - June 2014 1 FROM DOLPHINS TO DAMSELFISH - A MARINE BIOLOGIST’S PERSPECTIVE - Amy Deacon Editors Amy Deacon, Eddison Baptiste, 7 Associate Editor: Rupert Mends A BIRDER’S PERSPECTIVE - Matt Kelly Editorial Committee Eddison Baptiste, Elisha Tikasingh, Palaash Narase, Reginald Potter 15 THE BATS OF HUEVOS - Mark S. Greener Contributing writers Amy Deacon, Glenn Wilkes, Kris Sookdeo, 18 Mark Greener, Matt Kelly, Mike Rutherford THE TERRESTRIAL INVERTEBRATES OF HUEVOS Photographs - Mike G. Rutherford Amy Deacon, Glenn Wilkes, Mark Greener, Mike Rutherford, Kris Sookdeo, Matt Kelly, Jeffrey Wong-Sang. 21 THE LEPIDOPTERA REPORT - WORKING THE NIGHT SHIFT Design and Layout - Kris Sookdeo Eddison Baptiste 24 PHYSICAL GEOGRAPHY OF HUEVOS The Trinidad and Tobago Field Naturalists’ Club - Glenn Wilkes is a non-profit, non-governmental organization Management Committee 2014 - 2015 27 Management Notices President ……………... Kris Sookdeo 647-5556 Vice-President ……….. Palaash Narase 751-3672 28 Treasurer…………….. Selwyn Gomes 624-8017 Notes to Contributors Secretary ………...…... Eddison Baptiste 695-2264 Assist-Secretary ……... Yvette Adams Committee members ... Amy Deacon 390-0826 Dan Jaggernauth 659-2795 Glenn Wilkes 687-4604 Contact us! Email: [email protected] Editor’s note : Many thanks to all who contributed and Website: http://www.ttfnc.org assisted with articles and photographs. We would also like to thank Robert Boos for his permission to conduct this expedition, Facebook: https://www.facebook.com/pages/Trinidad- Tobago-Field-Naturalists-Club/68651412196 Youtube: https://www.youtube.com/channel/ Disclaimer : UCCNMeE7uIAbRPV6DCHSeEjA The views expressed in this bulletin are those of the respective authors and do not necessarily reflect the opinion and views Postal: The Secretary, TTFNC, c/o P.O. Box 642, of the Trinidad and Tobago Field Naturalists’ Club Port of Spain, Trinidad and Tobago Page 3 THE FIELD NATURALIST Issue No. 2/2014 - From Dolphins to Damselfish - surgeonfish, A. bahianus. Closer to the edges of the (Continued from page 1) bay were congregations of sergeant majors, Abudef- duf saxatilis and territorial dusky and biocolour dam- Many appeared to be ‘bow-riding’ with others trav- selfish, Stegastes adustus and S. partitus. These sight- elling alongside the boat. We estimated that there ings match well with Bonnie Tyler’s list made during were around 35 individuals; our boat driver in- the last TTFNC visit to the island in March 2012, formed us that although it is common to see dol- although we were not lucky enough to spot an eagle phins in this area, it was quite rare to see a group ray or barracuda as they did on that trip. that large. Interestingly, we observed tail slapping The island’s caretaker kept bait fishes in traps behaviour in two individuals, where the dolphin re- hanging from the jetty, and immediately underneath peatedly hits the surface of the water with its tail. one of these was an enormous, seemingly fearless, This is thought to be a means of communication in green moray, Gymnothorax funebris, presumably this species, although can also be associated with preying upon fish that were attracted to the filled aggression or feeding. The highlight of the encounter traps. Selwyn also spotted a green turtle (Chelonia was when one dolphin performed an impressive leap mydas) on the opposite side of the bay. ahead of the boat, which Jeffrey Wong Sang man- Having spent a few hours exploring the inland aged to capture on camera while the rest of us part of the island with the others, I decided to inves- watched in awe. We also noticed one very distinc- tigate the rocky shore. Both ends of the main beach tive individual, who was much paler than the others consisted of rocky outcrops, with large boulders on yet had evidently successfully reached adulthood in top of cobble. The rocks closer to the water were spite of this. covered in green algae making them extremely slip- On arrival on the island, we continued to watch pery underfoot. I very carefully explored the rocky the dolphins in the distance from the jetty. Here, I sections at both ends of the beach, turning (and re- ended up donning my mask and snorkel earlier than placing) those rocks that were light enough to lift as planned, when my (thankfully waterproof) camera I went. My knowledge of Caribbean intertidal fauna fell off the edge of the jetty, followed shortly by was not good enough to identify any species on the Graham’s hat, necessitating a double recovery mis- spot, but rather than collecting specimens I re- sion. This was successfully undertaken, and it was corded my finds photographically. not long before the other keen snorkelers among us Later, back in the UWI Zoology museum Mike had also taken to the water. Rutherford and I used museum specimens and an Learning lessons from the rather eventful 2012 array of dusty keys and guide books to identify as TTFNC trip to the island (see QB2 2012), we were many of the intertidal species as possible from my careful to stay close to shore and not to risk ventur- photographs. ing close to the Bocas channel. The visibility for In the splash zone, there were the pretty zebra snorkelling was not excellent, but the areas around periwinkles, Echinolittorina ziczac huddled within the jetty and surrounding shallows were sufficiently crevices (Fig. E) and bright orange ‘sally lightfoot’ clear for some enjoyable snorkelling. Here, Selwyn, crab, Grapsus grapsus, shed exoskeletons drying in Hameeda and Sheldon identified around 20 species the sun (Fig. K). Closer to the sea E. ziczac was re- of fish, including queen, grey and French angelfish, placed by another, darker periwinkle, probably Lit- Holacanthus ciliaris, Pomacanthus arcuatus, Pomacan- torina nebulusa. Venturing yet further into the inter- thus paru, stoplight parrotfish, Sparisoma viride, blue- tidal, two species of chiton were identified, the head wrasse, Thalassoma bifasciatum, white-spotted West Indian fuzzy chiton, Acanthopleura granulata filefish, Cantherhines macrocerus, French and blue- and the marbled chiton, Chiton marmoratus. Gastro- striped grunt, Haemulon flavolineatum and H. sciurus, pod molluscs were also well represented in this porkfish, Anisotremus virginicus, Spanish hogfish, Bo- zone. Cerithium sp., the tiny but beautiful white- dianus rufus, spotfin butterflyfish, Chaetodon ocellatus, spotted dove shell, Nitidella ocellata (Fig. D), the as well as the usual mixed shoals of blue tang, Acan- much larger wide-mouthed purpura, Purpura patella thurus coeruleus, doctorfish, A. chirurgus and ocean Page 4 THE FIELD NATURALIST Issue No. 2/2014 was the very same individual, still sitting on the (Fig. C) and chequered nerite, Nerita tessellata, as damp rock! I took some photos (Figs A and B), and well as several limpets (one of which we identified consulted some local fish experts once back on the as Lottia antillarium) and Gemophus sp (Fig. F). mainland, but the taxonomy of this group is appar- The decapod community included a wide vari- ently notoriously difficult, partly due to the huge ety of taxa. It seemed that nearly every boulder I number of species it encompasses. overturned revealed the surprisingly well- All in all, our trip to Huevos offered fantastic camouflaged pink Ozius reticulatus crab (Fig. L); inter- opportunities for getting a broad snapshot of the estingly, I never saw two crabs of this species under- marine fauna – from the unmissable dolphin acro- neath the same boulder. In contrast, hermit crabs, batics to the hidden secrets of the rocky shoreline. Clibanarius sp. (Fig. M) were found less frequently, On the next trip it would be of value to make a but when they were, they were present in aggregra- more systematic study of the marine and intertidal tions of 10 -20 individuals. Close to the water’s habitats, perhaps in the form of transect or quadrat edge, turning rocks frequently revealed the bizarre surveys. It would be interesting to get an idea of the but beautiful porcelain crabs, Petrolisthes quadratus, relative abundances of the marine fish, as well as to with their flattened claws and small round bodies, extend our (no doubt incomplete) species list. clinging to the underside of stones and shuffling backwards to escape. The sally lightfoot crabs were Footnote: scampering everywhere, too fast to photograph – On our return we were excited to report all details of until I discovered one tucked neatly in a crevice our dolphin encounter, including our photos and footage, to Alësha Naranjit of CCARO. By accumulating anec- peering out with its blue stalked eyes (Fig. J). One of my favourite finds was a tiny goby dotes and information such as ours, they hope to build a (~4cm), which I found out of the water on top of a better picture of T&T’s cetacean populations – including finding out more about abundance, distribution and habi- rock in the splash zone, near the house. On closer tat use which can then help in conservation management. examination it had a rasping sucker on its belly, and They are always happy to receive information about was clearly using this to stay put on the rock despite sightings, no matter how small or ‘ordinary’ and may be the waves.