409.

Dominican Myotis

Myotis dominicensis

French: Murin de la Dominique / German: Dominika-Mausohr / Spanish: Ratonero dominicano

Taxonomy. Myotis dominicensis G. S. Miller, 1902,

“Island of Dominica [Lesser Antilles], West Indies.”

Subgenus Pizonyx; albescens species group. See M. nigricans . Monotypic.

Distribution. Dominica and Guadeloupe, Lesser Antilles.

Descriptive notes. Head-body c.46 48 mm, tail 28-36 mm, ear 10-14 mm, hindfoot 7-9 mm, forearm 33-35.5 mm; weight 3-5 g. Fur is woolly and short to medium in length (dorsal fur 4-6 mm; ventral fur 4-5 mm). Ventral hairs are bicolored, with medium brown bases and reddish yellow tips. Bases and tips of dorsal fur contrast weakly, varying from bister to sudan brown, being lighter at tips. Ears are comparatively short, extending forward halfway from eye to nostril. Antitragal notch is barely evident. Membranes are mummy brown; plagiopatagium is attached to foot at toes by a broad band of membrane. Uropatagium fur extends halfway from knees to foot. Skull is small (greatest length ofskull 12:3-13- 4 mm); sagittal and lambdoidal crests are generally absent or, when present, are very low. P? is aligned in tooth row and visible in labial view. Mean bacula measurements ofsix specimens from Dominica were 0-60 long, 0-22 mm deep, and 0-31 mm wide. Wing morphology and echolocation are typical of aerial insectivores that use cluttered spaces.

Habitat. Well-preserved forests and near banana groves, open vegetable plots, coconut groves near a small riparian stream, and grazed pastures.

Food and Feeding. The Dominican Myotis is an aerial insectivore and forages in forested habitats and over water.

Breeding. Pregnant Dominican Myotis were recorded in April and lactating females in July. Reproductive data suggest seasonal polyestry. Embryos collected in April were described as early to mid-term, with crown-rump lengths of 7-12 mm.

Activity patterns. The Dominican Myotis starts its activities before sunset and forages throughout the night. It roosts in caves and other subterranean habitats. Meancall parameters are initial frequency of 95-2 kHz, terminal frequency of43-2 kHz, frequency of maximum energy of 53-7 kHz, call duration of 4-1 milliseconds, and pulse interval of 66 milliseconds.

Movements, Home range and Social organization. Colonies in Dominican Myotis can contain 200-300 individuals. In Dominica, several hundred individuals were observed flying together across a pasture, like a swarm. There was considerable organization to the group, which remained closely knit and organized in a ball shape, and it almost appearedlike flocking behavior.

Status and Conservation. Classified as Vulnerable on The IUCN Red List. The Dominican Myotis is known from only three locations on two Caribbean Islands (Dominica and Guadalupe). Its extent of occurrence is ¢. 6000 km?, but it is not found throughout the islands, so actual distribution is smaller than total size ofthe islands. Its habitat is declining due to expanding human activities, and hurricanes and severe weather can decrease local populations.

Bibliography. Barataud et al. (2015), Genoways etal. (2001), Larsen (2016a), Larsen, Larsen et al. (2012), LaVal (1973b), Miller & Allen (1928), Moratelli et al. (2017), Simmons (2005).