Nyctinomops macrotis, J. E. Gray, 1839

Don E. Wilson & Russell A. Mittermeier, 2019, Molossidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 598-672 : 638

46.

Big Free-tailed Bat

Nyctinomops macrotis

French: Grand Nyctinomope / German: GrolRe Bulldogfledermaus / Spanish: Nyctonimo grande

Taxonomy. Nyctinomus macrotis J. E. Gray, 1839 ,

“ Cuba.”

This species is monotypic.

Distribution. Patchily distributed from SW USA (SE Nevada, S Utah, and S Colorado) to S Mexico, the Greater Antilles ( Cuba, Jamaica, and Hispaniola), and South America in Colombia, Venezuela, Guyana, Suriname, Brazil, Ecuador, Peru, Bolivia, Paraguay, Uruguay, and N Argentina; it probably also occurs in French Guiana.

Extralimital records are reported as far N as SW Canada (British Columbia).

Descriptive notes. Head—body 73-89 mm, tail 40-63 mm, ear 24-32 mm, hindfoot 7-13 mm, forearm 54-65 mm; weight 17-34 g. Males are slightly larger than females. The Big Free-tailed Bat is the largest species in this genus. Dorsal fur ranges from reddish to blackish brown, hairs having whitish base; ventral furis slightly paler and sometimes with lightly frosted tips. Ears are large and hairy, with connection over forehead. Wings are long and narrow, and wing membrane is thin and leathery. Legs are short and strong. Upperlips are wrinkled and overhang lower lip. I* is nearly vertical and parallel in front view. Chromosomal complement has 2n = 48 and FN = 58.

Habitat. Dry forest, thorn forest, wet forest, scrubland, and savanna, from sea level to 2600 m in elevation.

Food and Feeding. The Big Free-tailed Bat feeds mainly on large moths ( Lepidoptera ), but also eats crickets ( Gryllidae ), bush crickets ( Tettigoniidae ), flying ants ( Formicidae ), stinkbugs ( Pentatomidae ), froghoppers ( Cercopidae ), and leathoppers ( Cicadellidae ).

Breeding. One young is born in late spring or early summer. Pregnant females were found from April to July, and lactating females have been documented from June to October; most of these data are from the northern part of the range. A suckling young attached to the mother was reported in September.

Activity patterns. The Big Free-tailed Bat usually does not leave its day roost until after dark to forage, but it has been documented flying at dusk. Itis a strong flier that does not need to drop from its roost to take flight, as do most other molossids. This species roosts in tree hollows, rock crevices, cracks of cliffs, caves, buildings, and bridges. The searchphase echolocation call is a long, narrowband, single harmonic signal with a downward FM with an average peak frequency of 20-2 kHz. Owls are known to prey on this species.

Movements, Home range and Social organization. The Big Free-tailed Bat is reported to roost singly, but also forming colonies of up to 150 individuals. During summer, there is sexual segregation with females and young in maternity colonies. In the northern part of its range,it exhibits migratory behavior.

Status and Conservation. Classified as Least Concern on The IUCN Red List.

Bibliography. Arita (2014e), Eger (2008), Milner et al. (1990), Mora & Torres (2008), Rocha et al. (2015), Silva-Taboada (1979), Warner et al. (1974).

Figures

42. Mato Grosso Dog-faced Bat (Neoplatymops mattogrossensis), 43. Peale’s Free-tailed Bat (Nyctinomops aurispinosus), 44. Pocketed Free-tailed Bat (Nyctinomops femorosaccus), 45. Broad-eared Free-tailed Bat (Nyctinomops laticaudatus), 46. Big Free-tailed Bat (Nyctinomops macrotis), 47. Equatorial Dog-faced Bat (Cabreramops aequatorianus), 48. Rufous Dog-faced Bat (Molossops neglectus), 49. Dwarf Dog-faced Bat (Molossops temmancku), 50. Freeman's Dog-faced Bat (Cynomops freemani), 51. Mexican Dog-faced Bat (Cynomops mexicanus), 52. Southern Dog-faced Bat (Cynomops planirostris), 53. Cinnamon Dog-faced Bat (Cynomops abrasus), 54. Greenhall’s Dog-faced Bat (Cynomops greenhalli), 55. Thomas's Dog-faced Bat (Cynomops mastivus), 56. Miller's Dog-faced Bat (Cynomops milleri), 57. Waorani Dog-faced Bat (Cynomops tonkigui)

Distribution. Patchily distributed from SW USA (SE Nevada, S Utah, and S Colorado) to S Mexico , the Greater Antilles ( Cuba , Jamaica , and Hispaniola), and South America in Colombia , Venezuela , Guyana , Suriname , Brazil , Ecuador , Peru , Bolivia , Paraguay , Uruguay , and N Argentina ; it probably also occurs in French Guiana . Extralimital records are reported as far N as SW Canada (British Columbia).