Bats of the West Indian Island of Dominica: Natural History, Areography, and Trophic Structure
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University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Mammalogy Papers: University of Nebraska State Museum Museum, University of Nebraska State 2-7-2001 Bats of the West Indian Island of Dominica: Natural History, Areography, and Trophic Structure Hugh H. Genoways University of Nebraska - Lincoln, [email protected] Carleton J. Phillips Texas Tech University Robert M. Timm University of Kansas Duane A. Schlitter Texas A & M University Follow this and additional works at: https://digitalcommons.unl.edu/museummammalogy Part of the Zoology Commons Genoways, Hugh H.; Phillips, Carleton J.; Timm, Robert M.; and Schlitter, Duane A., "Bats of the West Indian Island of Dominica: Natural History, Areography, and Trophic Structure" (2001). Mammalogy Papers: University of Nebraska State Museum. 105. https://digitalcommons.unl.edu/museummammalogy/105 This Article is brought to you for free and open access by the Museum, University of Nebraska State at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Mammalogy Papers: University of Nebraska State Museum by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Museum of Texas Tech University Number 43 7 February 2001 BATS OF THE WEST INDIAN ISLAND OF DOMINICA: NATURAL HISTORY AREOGRAPHY, AND TROPHIC STRUCTURE HUGH H. GENOWA YS ROBERT M TIMM ROBERTJ. BAKER CARLETON J. PHILLIPS AND DUANEA. SCHLITTER Museum of Texas Tech University NUMBER43 BATSOF THE WESTINDIAN ISLAND OF DOMINICA: NATURALHISTORY, AREOGRAPHY, AND TROPHICSTRUCTURE HUGHH. GENOWAYS,ROBERT M. TIMM,ROBERT J. BAKER, CARLETONJ. PHILLIPS,AND DUANEA. SCHLITTER University of Nebraska State Museum, University of Kansas, Texas Tech University, and Texas A&M University Layout and Design: Jacqueline B. Chavez Cover Design: Angie Fox Copyright 2001, Museum of Texas Tech University All rights reserved. No portion of this book may be reproduced in any form or by any means, including electronic storage and retrieval systems, except by explicit, prior written permission of the publisher. This book was set in Times New Roman and printed on acid-free paper that meets the guidelines for permanence and durability of the Committee on Production Guidelines for Book Longevity of the Council on Library Resources. Printed: 07 February 200 1 Library of Congress Cataloging-in-Publication Data Special Publications, Number 43 Series Editor: Robert J. Baker The Bats of Dominica Hugh H. Genoways, Robert M. Timm, Robert J. Baker, Carleton J. Phillips, and Duane A. Schlitter ISSN 0169-0237 ISBN 1-929330-00-6 Museum of Texas Tech University Lubbock, TX 79409-3 19 1 USA (806)742-2442 Because the islands in the Caribbean long have agricultural practices. Land under cultivation gener- interested students of mammals and zoogeography, ally is scattered along the coasts, especially in small considerable information has been published concern- pockets on the alluvial plains of the many rivers, ing the biology of the Antillean mammalian fauna in whereas the center of the island is mostly forested. the past three decades (Jones and Schwartz, 1967; Schwartz and Jones, 1967; Koopman, 1968, 1989; The dominant physiographic feature of the is- Jones and Phillips, 1970, 1976; Varona, 1974; Baker land is a north-south mountain chain. The highest and Genoways, 1978; Baker et al., 1978; Swanepoel point is Morne Diablotin (1450 m) in the north-central and Genoways, 1978; Jones and Baker, 1979; Silva part of the island; Morne Trois Pitons (1400 m) is the Taboada, 1979; Baker et al., 1984; Eshelrnan and Mor- tallest peak in the south-centralpart of the island. These gan, 1985; Buden, 1986; Gnffiths and Klingener, 1988; peaks are surpassed in height in the Lesser Antilles Jones, 1989; Masson et al., 1990; Pederson et al., only by Morne Soufriere on nearby Guadeloupe. A 1996; Genoways et al., 1998). This increasing inter- plateau, lying between two chains of mountains at an est in the systematics and zoogeography of mammals altitude of 460 m to 610 m, covers the center of the in the region has involved both studies in the field and island. There are at least eight mountains around this re-examination of collections made in earlier years. plateau with an elevation of 915 m or more and two One problem facing investigators who attempt to as- smaller peaks higher than 6 10 m. sess the faunal relationships of the Antilles is the fact that natural conditions on most islands have been al- The Layou River, the largest river on the island, tered significantly as a result of early settlement, first flows westward between Morne Diablotin and Mome by Ameridians, then by Europeans beginning in the Trois Pitons and drains in the central plateau. Most of 1500s. Changes wrought by agricultural practices have the rivers on Dominica flow east or west from the destroyed much of the original environment, and in- precipitous heights of the center of the island. Deep troduction on many islands of the mongoose (Herpestes ravines and youthful valleys radiate from all the moun- javanicus) as a supposed means of controlling intro- tains and are bordered by ridges that generally run to duced rats (both Rattus nowegicus and R. rattus) has the coast, ending in sea-cliffs, especially on the north disturbed natural conditions. and south ends of the island. Because of the rugged nature of the interior and the lack of extensive flatlands One island favorable for the investigation of the, along the coasts, the vegetation has been disturbed natural history of mammals is Dominica, the north- less by agriculture than on most, if not all, other is- ernmost of the Windward Islands. With an area of lands of the Lesser Antilles. 800 square kilometers, Dominica is the third largest island in he Lesser Antilles (only Guadeloupe and The climate of the Lesser Antilles varies consid- Martinique are larger). The island is approximately 45 erably over a short distance (Beard, 1949). The gen- kilometers long and 24 kilometers wide at the widest eral climate pattern on Dominica is a dry season from point. It is located near the center of the Lesser January through May and a humcane season from Antillean chain, between 15O10' and 15'40' north lati- July to September. Major hurricanes occur approxi- tude, and 61°1 5' and 6199' west longtude; Guadeloupe mately every 15 to 20 years, with the most recent to the north and Martinique to the south are about equi- being Hurricane David in 1979 and to a lesser extent distant (approximately 40 kilometers) from the island. Hurricane Hugo in 1989. A "dry belt" climate is present The smaller Marie Galante is only 30 kilometers to the on the leeward coast (Beard, 1949), where rainfall northeast. Dominica contains the highest and most measures between 900 mm to 1670 mm a year; mean rugged terrain of any in the Lesser Antilles, and is one annual temperature is about 26°C: and the mean rela- of the few islands where mongoose have not been tive humidity is approximately 75 percent. The re- introduced. Beard (1949:108) noted that Dominica is mainder of the island consists of "mountain and upper 80 percent forested, and it remains the most pristine mountain belt" climate (Beard, 1949). More than 2565 of any in the Lesser Antilles. The forest is mainly rain rnm of rainfall is regularly recorded at windward coast forest although much is secondary owing to shifting weather stations, more than 5130 rnm at the stations in the zone of rain forest, and precipitation may be as Archbold-Smithsonian Biological Survey of Dominica, much as 10,250 mm on the highest mountain peaks, visited the island on three occasions, begnning in 1966 although exact measures on peaks are unrecorded when he collected from late March until late April. He (Hodge, 1954). Relative humidity seldom falls below returned to the island in 1967 accompanied by Carleton 85 percent in the interior of the mountain and upper J. Phillips when they collected from August 27 until mountain belt. Temperature averages about 21°C, but September 2. Finally, Jones visited Dominica with temperature varies with altitude and season with the Robert J. Baker from July 19 to 27,1978. Other speci- lowest temperatures in February and March. mens of bats from Dominica in the collections of the Museum of Texas Tech University were obtained when The first published reference to a bat collected Robert D. Owen and classes of students collected in on Dominica was by Oldfield Thomas (1 891) in refer- June and July of 1991 and 1992. These investigations ence to Ardops nichollsi. H. S. Branch in 1901 made resulted in the collection of large series of bats, thereby significant collections of bats on the island and A. H. providing the materials for an up-to-date survey of the Verrill made a small collection of bats there in 1906. chiropteran fauna of Dominica. These specimens were Few specimens were collected in-the half-century that accompanied by a wealth of natural history infornla- followed; however, in the late 1950s through the mid- tion, which is summarized here. With completion of 1970s, in addition to herpetological investigations, this major survey, we have taken the opportunity to Albert Schwartz and associates obtained bats on investigate the areography (Udvardy, 1969) of this Dominica and other Antillean islands on several occa- island's chiropteran fauna to gain a better understand- sions. J. Knox Jones, Jr., under the aegis of the Bredin- ing of its position within the West Indies. I). Y' I). I9 61- 3W 6I'lS' Figure 1. Reference points for localities of specimens of the chiropteran fauna of Dominica. Numbers correspond with locations listed in gazetteer. All measurements in the accounts that follow are of crown-rump length. Capitalized color terms are in millimeters and weights are given in grams.