Cave Bats in Jamaica Donald A
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Cave bats in Jamaica Donald A. McFarlane Jamaica has 22 native mammal species. One may cause serious disturbance to the colonies. of these is an endangered rodent, the Wallingford Cave, in St Elizabeth Parish, is a large Jamaican hutia Geocapromys browni; the rest but short blind tunnel close to a road that was for a are all bats. Fifteen of these bats depend time mined for its guano deposits (Peck, 1975). entirely or significantly on caves as roost sites, By August 1977 the bat colony had disappeared, including two endemic species and seven and it seems possible that excessive disturbance endemic subspecies. These cave-dwelling bats may have been responsible. often form large colonies whose guano deposits are of significant economic value as An examination of the literature suggests that 15 fertilizer, but which are vulnerable to disturb- of Jamaica's bats are significantly or entirely ance and roost destruction. The author, who dependent on caves as day roosts (Table 1). Six has visited and worked in many of Jamaica's of these species are of special concern and are bat caves over the past eight years, is currently discussed below. Taxonomy and vernacular researching the evolution and development of names follow Hall (1982). the Antillean bat faunas. The Jamaican flower bat Of Jamaica's 950 documented caves (Fincham, Phyllonycteris aphylla 1977), approximately 17 per cent are known to host bat colonies of sizes varying from a few This bat is endemic to Jamaica and is known from dozen to tens of thousands of individuals. The only three caves: St Clair Cave, Riverhead Cave, cave-dwelling bats of Jamaica are not evenly dis- and Mt Plenty Cave (Goodwin, 1970). Its sub- tributed amongst these caves, and a mere handful fossil remains have been found in 'Dairy Cave' of large caves account for all the known colonies (Runaway Bay Caves) and Wallingford Cave of some of the rarest species. These caves are (Koopman and Williams, 1951). Its total pop- typically occupied by several species of bat whose ulation is unknown, but the only sizeable colony is combined numbers produce large quantities of in St Clair Cave and numbers perhaps a few guano, which may be harvested commercially as hundred individuals. The fact that P. aphylla is no a high-grade fertilizer. Indeed, one of the first longer found at Runaway Bay and Wallingford systematic surveys of Jamaican caves was under- Caves suggests that there may have been some taken by the Geological Survey Department of abandonment of former roosts. Alternatively, if Jamaica specifically to locate and assess the subfossils from these caves are owl pellet economic reserves of bat guano (McGrath, remains rather than roost deposits, then the status 1950-1965). Ironically, this commercial interest of this species in these areas is completely both threatens and, perhaps, protects the unknown. animals. Clearly, it is in the interests of those As far as is known, P. aphytta is a gregarious, landowners who harvest guano to ensure the obligate cave dweller forming colonies of up to a continued well-being of the bat colonies in their few hundred individuals in large cave passages caves, but at the same time careless harvesting shared with other species. Such caves are few in Cave bats in Jamaica 27 Downloaded from https://www.cambridge.org/core. IP address: 170.106.40.40, on 27 Sep 2021 at 10:58:21, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0030605300025874 Table 1. Jamaica's cave bats and their distribution in the island's important bat caves Important caves Jamaican cave bats Obligate cave dweller? Endemic? StClair Oxford Windsor Mt Plenty Pteronotus quadridens fuliginosus Yes No Pteronotus macleayii griseus Yes Subspecies Pteronotus pamelli pamelli Yes No Aello cuvieri Yes No Macrotus waterhousii jamaicensis No? Subspecies Glossophaga sorcina antillarum Yes No Monophyllus redmani redmani Yes Yes Artibeus jamaicensis jamaicensis No No Erophylla sezekomi syops Yes Yes Phyllonycteris aphylla Yes Yes Natalus stramineus major Yes Yes Natalus microps Yes Yes Eptesicus lynni Yes? Yes? Molossus molossus milleri No No Tadarida macrotis No? No number and are typically associated with on pollen and nectar feeding, so that it is likely abandoned river resurgences. Little else is known that the species would exhibit a dietary shift from of the ecology of this bat. Novick and Leen pollen and nectivory in the dry season to frugiv- (1969) report that P. aphylla is unable to bite into ory in the wet season. Goodwin (1970) reports a firm fruit, but feeds on juice and pulp from over- female with embryo taken in late January, but ripe and damaged fruit on the ground. The nothing else is known of the species's repro- papillose, protusible tongue implies an emphasis ductive habits. Bats in the roof of Oxford Cave, Jamaica (Donald A. McFarlane). Oryx Vol 20Nol, January 1986 Downloaded from https://www.cambridge.org/core. IP address: 170.106.40.40, on 27 Sep 2021 at 10:58:21, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0030605300025874 The buffy flower bat Erophylla Windsor Cave population is of unknown size, sezekorni syops since only a single individual has been trapped there. These bats are strictly insectivorous, and This is a rare endemic subspecies of a genus apparently rather slow fliers. restricted to the Greater Antilles and Bahamas, and is known from just three caves: Mt Plenty Cave, Sewell Cave and St Clair Cave. Only the St Clair Cave population is known to be of any size, The Mexican funnel-eared bat Natalus numbering at most several hundred individuals stramineus jamaicensis (Goodwin, 1970). From what little is known, the This endemic subspecies is apparently even rarer ecology of the species is similar to that of P. and less well known than N. micropus. Living aphylla. The species is apparently much more animals are known only from St Clair Cave, common on Cuba (Nowak and Paradiso, 1983), where the population is crudely estimated to be which suggests that the Jamaican subspecies has only about one-third of that of N. micropus either escaped attention or perhaps is in decline. (Goodwin, 1970). A single subfossil specimen has been recovered from Wallingford Cave The Cuban funnel-eared bat Natalus (Koopman and Williams, 1951). The ecology of micropus micropus the species is presumed to be similar to that of N. This endemic subspecies is known from three micropus and the mainland forms of N. localities: St Clair Cave (Goodwin, 1970), stramineus, which are themselves poorly studied. Monarva Cave (personal observation, 1983) and Windsor Cave (Kerridge and Baker, 1978). Each of these caves is warm, very humid, and supports Lynn's brown bat Eptesicus lynni a large population of several bat species. In St This endemic species is known only from the Clair Cave the population has been estimated at original discovery in an unnamed cave near several hundred, and the species is probably Montego Bay (Shamel, 1945), three misidenti- present in Monarva Cave in similar numbers. The fied specimens caught in Sherwood Forest Key to caves mentioned in text: 1. Monarva Cave 7 San Souci Grotto 2. Sewell Cave 8. Mt Plenty Cave 3. Windsor Great Cave 9. Moseley Hall Cave km 50 4. Oxford Cave 10. Riverhead Cave 5. Wallingford Cave I I. St Clair Cave 6. Runaway Bay Caves 12. Jackson's Bay Caves Figure 1. Important bat caves of Jamaica. Cave bats in Jamaica 29 Downloaded from https://www.cambridge.org/core. IP address: 170.106.40.40, on 27 Sep 2021 at 10:58:21, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0030605300025874 (Sanbom, 1941), and a more recent collection of under direct threat other than through disturb- three specimens from Runaway Bay Caves ance by excessive numbers of curious visitors or (quoted as 'Green Grotto') (Arnold eta/., 1980). guano diggers. Legislation to protect some of the Nothing is known of its ecology, but its morpho- more important caves—these would include logical similarity to other members of its genus Oxford, Mt Plenty, Windsor and St Clair Caves- suggests that it is an aerial insectivore. The would serve to focus official attention and proposed South American affinities of this species monitoring on these sites, but in realistic terms make it of special interest in the understanding of such legislation would be unenforcable as a prac- Caribbean zoogeography. tical measure. Since most of these caves are located on or near smallholdings or other agri- cultural concerns, probably the best protection Leach's long-tongued bat would be afforded through education at the Monophyllus redmani redmani agricultural development centres, which offer advice and training to farmers throughout the An endemic subspecies of a genus confined to the island. Furthermore, in the event that Jamaica Antilles and Bahamas, M. redmani has been does establish national parks in any of the recorded from six Jamaican caves: Oxford Cave, remaining wilderness areas (see Mittermeier, Moseley Hall Cave, St Clair Cave, Windsor 1972) it is to be hoped that due attention will be (Great) Cave, Mt Plenty Cave and San Souci paid to the unique but poorly understood bat Grotto (Goodwin, 1970; personal observation, fauna. 1983). The anatomy of the tongue and muzzle suggests a largely nectivorous habit similar to that References of the better known Glossophaga sorcina, which Arnold, M.L., Baker, R.J. and Genoways, H.H. 1980. Evo- takes soft fruit, nectar and insects. Pregnant lutionary origin of Eptesicus lynni. Journal of Mammalogy, Monophyllus caught in December, January and 61 (2), 319-322.