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Iguana 15.3 b&w text 9/10/08 5:43 AM Page 130 130 IGUANA • VOLUME 15, NUMBER 3 • SEPTEMBER 2008 DANIELLS ET AL. NATALIE N. WYSZYNSKI N. NATALIE Populations of Lesser Antillean Iguanas (Iguana delicatissima) have declined or disappeared on many islands. Those on Dominica are doing well and may serve as a model for developing management strategies for other islands (see IGUANA 14(4), p. 222). Iguana 15.3 b&w text 9/10/08 5:43 AM Page 131 AMPHIBIANS AND REPTILES OF DOMINICA IGUANA • VOLUME 15, NUMBER 3 • SEPTEMBER 2008 131 An Annotated Checklist of the Amphibians and Reptiles of Dominica, West Indies Esther A. Daniells1, Jeffrey W. Ackley2, Ruth E. Carter3, Peter J. Muelleman4, Seth M. Rudman5, Patrick A. Turk6, Nelson J. Vélez Espinet7, Lauren A. White8, and Natalie N. Wyszynski9 1Department of Biology, Colorado State University, Fort Collins, CO 80523 ([email protected]) 2Department of Biology, Eckerd College, St. Petersburg, FL 33711 ([email protected]) 3Department of Biology, Earlham College, Richmond, IN 47374 ([email protected]) 4Department of Biology, Truman State University, Kirksville, MO 63501 ([email protected]) 5Department of Biology, University of Rochester, Rochester, NY 14627 ([email protected]) 6Department of Biology, Avila University, Kansas City, MO 64145 ([email protected]) 7Department of Biology, University of Puerto Rico, Río Piedras, PR 00931 ([email protected]) 8Environmental Science Program, Oklahoma State University, Stillwater, OK 74078 [email protected]) 9Department of Psychology, University of Tennessee, Knoxville, TN 37996 ([email protected]) ! ravel writers have suggested that if Christopher Columbus Twere to take a Caribbean cruise today, Dominica might be the only West Indian island he would recognize. In an age when an ideal tropical paradise must include golf courses, five-star restaurants, towering hotels, cruise-ship berths, manicured white beaches, and swimming pools adjacent to the ocean, the drastic changes to which other destination islands have been subjected are understandable. However, an accident of geology spared Dominica from that fate. The island is a complex of volcanic peaks, the highest of which (Morne Diablotin) reaches 1,446 m above sea level, resulting in an intimidating terrain that has slowed the seemingly inevitable march of “progress.” Because level lowlands suitable for sugarcane plantations during the colo- nial era do not exist and tourism-oriented development is min- imal, the inevitable consequences of deforestation and declining biodiversity are largely absent. In sharp contrast, the potential for effective conservation is considerable, and Dominican authorities have taken steps to pre- serve two unique natural treasures: The forests, which still cover more than 60% of the island, and the animals that live in the largely natural habitats that remain. The amphibians and reptiles in particular comprise what may well be the most “natural” her- petofaunal community in the entire Lesser Antillean archipelago. Although conserving forests and their inhabitants might not be a selling point for the vacationers to whose interests devel- opers cater, Dominica benefits by promoting ecotourism, and markets itself as the “Nature Island.” By not competing for vis- itors whose sole interest is reclining in the lap of luxury, Dominica provides the chance to experience natural habitats, increasingly rare commodities that more intensely developed islands are about to lose entirely. However, in order to place a value on natural resources such as the herpetofauna, authorities must have access to reliable information about its distribution, JOHN S. PARMERLEE, JR. 2 natural history, and conservation status. Herein we present a Dominica (754 km ) is one of the volcanic Windward Islands in the Lesser Antilles. The rugged topography and lack of flat lowlands spared summary of our observations on Dominica’s diverse herpetofau- the island from the alterations (typically associated with sugar planta- nal communities with the hope that it will remain relevant to tions) to which most other West Indian islands were subjected during coming generations. the colonial period. Iguana 15.3 b&w text 9/10/08 5:43 AM Page 132 132 IGUANA • VOLUME 15, NUMBER 3 • SEPTEMBER 2008 DANIELLS ET AL. Frogs (Amphibia: Anura) Eleutherodactylus amplinympha (Kaiser, Green, and Schmid 1994). Anura: Eleutherodactylidae. Local name: Dominican Gounouj. English common names: Dominican Frog, Dominican Rain Frog, Dominican Whistling Frog. Endemic. These relatively small frogs (maximum male SVL 26 mm, max- imum female SVL 50 mm) occur at elevations >300 m in mon- tane rain forest, where they perch on trees, palm brakes, moss mats, epiphytes, and ferns. This species has a pointed snout and relatively large toepads. Males have bi-lobed glandular vocal sacs and produce a three-note call. Dorsal color varies from brown- ish to greenish to reddish, and, as in other frogs in the genus, ROBERT POWELL pattern elements are highly variable. These largely nocturnal The Lesser Antillean Frog (Eleutherodactylus johnstonei) has been frogs are known to call by day in wet forests during or after recorded from Dominica. Although it has successfully colonized other heavy rains. The species is included on the IUCN Red List as islands, where it has displaced native species, it has not been found dur- “endangered,” primarily due to its restricted range, high likeli- ing recent surveys, suggesting that the colonization of Dominica has hood of habitat loss attributable to human expansion, volcan- failed. This frog was photographed on St. Vincent. ism, or hurricanes, and the potential threat posed by chytrid- iomycosis, a fungal infection to which upland amphibians in the tropics appear to be particularly vulnerable. to document the presence of this species on Dominica and it is no longer included in the list of Dominican amphibians. This species is included on the IUCN Red List as being of “least con- cern,” largely attributable to its colonizing ability, which is unusual among amphibians, which generally have little tolerance for exposure to saltwater. Introduced populations on some islands compete successfully with native species, and often dis- place them, especially from altered habitats. Eleutherodactylus martinicensis (Tschudi 1838). Anura: Eleutherodactylidae. Local name: Tink Frog. English common names: Martinique Frog, Martinique Robber Frog. This Lesser Antillean endemic is presumably native on Dominica, although ROBERT POWELL it may have been imported inadvertently by early European set- The endangered Dominican Frog (Eleutherodactylus amplinympha) is tlers. These small frogs (maximum male SVL 32 mm, maximum restricted to moist forests at higher elevations. female SVL 47 mm) occur from sea level to at least 1,250 m in varied natural and altered habitats that include rain forests, dry woodlands, banana and coconut plantations, and gardens. This Eleutherodactylus johnstonei (Barbour 1914). Anura: species has a pointed snout and relatively small toepads. Males Eleutherodactylidae. No local name. English common names: have a bi-lobed glandular vocal sac and produce a two-note call. Lesser Antillean Frog, Johnstone’s Whistling Frog, Johnstone’s Dorsal color is brownish to reddish; other markings are highly Robber Frog. Lesser Antillean endemic, introduced on variable. These nocturnal frogs may call by day during or after Dominica, other West Indian islands, and the South American mainland. These frogs are thought to have been introduced on Dominica after Hurricane David in 1979, probably with relief supplies from neighboring islands. Throughout their extended range, these small frogs (maximum male SVL 25 mm, maxi- mum female SVL 35 mm) thrive in artificial sites such as resi- dential gardens, agricultural areas, roadsides, and buildings from sea level to elevations of ~1300 m. This species has a rounded snout and relatively small toepads. Males have a single-lobed glandular vocal sac and produce a two-note call. Dorsal ground color usually is some shade of brown; other markings are highly variable. Where the two species occur together, E. johnstonei often is confused with closely related E. martinicensis. ROBERT POWELL Eleutherodactylus johnstonei is a nocturnally active sit-and-wait Like many relatives, patterns of Martinique Frogs (Eleutherodactylus predator with a diet composed primarily of small arthropods. martinincensis) are highly variable. This individual has a faint middor- Documented predators include Turnip-tailed Geckos sal line, but others may be unicolored, blotched, or have very distinct (Thecadactylus rapicauda) and snakes. Recent surveys have failed dorsal “racing” stripes. Iguana 15.3 b&w text 9/10/08 5:43 AM Page 133 AMPHIBIANS AND REPTILES OF DOMINICA IGUANA • VOLUME 15, NUMBER 3 • SEPTEMBER 2008 133 heavy rains. They feed on a variety of small arthropods, and have turnal, although some foraging and calling may occur on rainy been observed foraging at night for insects attracted to lights. days. The species is included on the IUCN Red List as “critically Predators include snakes and larger frogs. Fungal infections endangered,” largely due to excessive exploitation as a delicacy. (chytridiomycosis) have been documented. This species is Other factors that have contributed to population declines are included on the IUCN Red List as “near threatened,” due to a invasive predators (pigs, cats, rats, and dogs), habitat loss by known range of less than 5000 km2 and potential habitat loss