381.

Long-legged Myotis

Myotis volans

French: Murin a longues pattes / German: Langbeiniges Mausohr / Spanish: Ratonero de patas largas

Other common names: Hairy-winged Myotis

Taxonomy. Vespertilio volans H. Allen, 1866,

Cape St. Lucas [= Cabo San Lucas], Lower [= Baja] Cal[ifornia].,” Mexico.

Subgenus Pyzonix; lucifugus species group. See M. evotis . Four subspecies recognized.

Subspecies and Distribution. M.v.volansH.Allen,1866—NWMexico(BajaCalifornia).

M.v.amotusG.S.Miller,1914—SCMex-ico.

M.v.interiorG.S.Miller,1914-SCCan-ada(SSaskatchewan),W&CUSA(SEWashington,EOregon,Idaho,Montana,WNorthDakota,WSouthDakota,Wyoming,E&SCalifornia,Nevada,Utah,Colorado,WNebraska,Arizona,NewMexico,andW&NTexas),andNMexico.

M. v. longicrus True, 1886 — W Canada (SW Yukon, British Columbia including Vancouver I, and S Alberta) and W USA (extreme SW Alaska, Washington, W Oregon, and NW & WC California).

Descriptive notes. Head—-body 43-63 mm, tail 40-50 mm, hindfoot 8-11 mm, ear 12-15 mm, forearm 38-42 mm; weight 5-10 g. Dorsal pelage of the Long-legged Myotis is dark brown to reddish brown, occasionally blond; venter is lighter. Bare face, ears, and membranes are generally brown, but face and ears often match fur’s color. Snout is short and furred nearly to nose. Ears are medium-sized, with rounded tips; tragus is moderately long and pointed. Calcar is distinctly keeled, and underside of wing is lightly furred near body to a line from elbow to knee; hindfeet are small; and wing attaches to hindfoot at middle of metatarsus. Skull has short rostrum, smoothly rising forehead, and elevated occiput. Chromosomal complement has 2n = 44 and FN = 50.

Habitat. Primarily mountainous areas dominated by coniferous forests but also oak and riparian woodlands and deserts at elevations of 60-3770 m (typically 2000-3000 m).

Food and Feeding. [.ong-legged Myotis eat a variety of insects (e.g. Diptera, Isoptera, Neuroptera, Hymenoptera, Homoptera, and small Coleoptera) but favor Lepidoptera . In Idaho, feces contained Lepidoptera (49-2% volume, 100% frequency), Coleoptera (31:1%, 100%), and smaller amounts of Diptera, Hemiptera, Hymenoptera, Trichoptera, and Neuroptera . They are rapid and directfliers and have been recorded at speeds of 15-17 km /h. When hunting, they are known to pursue prey through, under, and over forest canopies and can detect prey at 5-10 m.

Breeding. [.ong-legged Myotis breed in late summer and autumn beginning in August. Spermatogenesis begins in August in New Mexico but is repressed until winter hibernation months, followed by spermiogenesis primarily in May-August (peak in July). Females store sperm until ovulation occurs after hibernation in March—May. Births of single young occur in May-August. Depending on location, pregnant females have been caught from mid-April to mid-August. Males appear to become sexually active in their first year, at least in Alberta. A banded individuallived up to 21 years old.

Activity patterns. Long-legged Myotis leave roosts in early evening well before dark and generally eat their fill in the first 30 minutes of foraging, but there is a peak in general activity in the first 3—4 hours after sunset. Individuals rest in night roosts in buildings, caves, or mines. They have been most active at temperatures of 12-18°C, but they likely have a wider temperature range for activity. During the day, they roost primarily in trees but also occasionally rock crevices and abandoned buildings; caves are not used during the day. In winter, these bats congregate in caves and mines to hibernate. Calls are steep FM sweeps, with average start frequency of 89 kHz, end frequency of 40 kHz, peak frequency of 46 kHz, and maximum duration of 10 milliseconds in Arizona.

Movements, Home range and Social organization. During spring and summer, female Long-legged Myotis roost in large maternity colonies that can include hundreds of individuals; males roost alone. They move short distances locally when moving between hibernacula and summer foraging areas.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Longlegged Myotis does not face any major threats, but local roost disturbance is likely a threat to hibernating individuals. DDE, DDT, and DDD residues were found in carcasses and brains of Long-legged Myotis in eastern Oregon, suggesting bioaccumulation of pesticides is a threat.

Bibliography. Anderson (1968), Baker & Lacki (2006), Bickham (1979b), Dalquest & Ramage (1946), Druecker (1972), Fenton & Bell (1979, 1981), Fenton et al. (1980), Findley (1954, 1972), Genoways (1967), Herder & Jackson (2000), Johnson et al. (2007), Lacki, Baker & Johnson (2010, 2012), Lacki, Johnson & Baker (2013), Morales & Carstens (2018), Ormsbee (1996a, 1996b), Ormsbee & McComb (1998), Platt et al. (2018), Schowalter (1980), Slough etal. (2014), Solari (2019m), Warner & Czaplewski (1984), West (1993), Whitaker, Maser & Cross (1981), Whitaker, Maser & Keller (1977).