Myotis thysanodes FRINGED MYOTIS. Description

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1 symbiotic bacteria. Digestion of chitin in bat guts is incomplete so fecal pellets of bats usually include identifiable remains of their insect prey. Little brown bats-like a number of other kinds of bats-exhibit remarkable longevity for small mammals. Oldest reported age is over 30 years (Fenton and Barclay 1980) and many survive more than 10 years. Mortality is highest in the first year, occurring mostly as the young learn to fly or during their hibernation. Foraging skills must develop, so the young are not as adept as adults. Based on a study of specimens (reported as M occultus) from New Mexico and southern Colorado, ectoparasites include a wide variety of mites and also fleas, bat bugs (Cimicidae), and bat flies (Nycteribiidae) (E. Valdez et al. 2009), A variety of predators feed on these bats, including snakes, passerine birds, birds of prey, domestic pets, and other small carnivores. Documented predators of the little brown myotis include fish, snakes, owls and other birds, and house cats (Sparks et al. 2000). Rabies appears to be rare. Myotis thysanodes FRINGED MYOTIS Description The fringed myotis is yellowish brown to reddish brown, with the ventral color similar to the dorsum. The ears are quite large, extending 3-5 mm beyond the nose when laid forward. The free edge of the interfemoral membrane has an obvious fringe of stiff hairs, hence the common name. This feature most readily distinguishes this bat from others in Colorado. Measurements are: total length mm; length of tail 34-45; length of hindfoot 9-11 mm; length of ear mm; length of forearm mm; wingspan em (R. Adams 2003); weight 6-7 g. The skull is relatively large, slender, and fragile; greatest length of skull is mm. A well-developed sagittal crest is present. D1git1zed by Goog le

2 PHOTOGRAPH Fringed myotis (Myotis thysanodes). Photograph by Roger W. Barbour. D~scriptien A western species, the fringed my otis is an animal of coniferous woodlands and shrublands at elevations to 2,290 m (7,500 ft.). The few Coloradan records are widely scattered both east and west of the Continental Divide (J. Fitzgerald et al. 1989). D. Armstrong (1972) reported a specimen from Wooton, near Raton Pass, but the species probably occurs farther east along the New Mexico boundary, as Dalquest et al. (1990) reported the animals from the northeastern comer of Union County, New Mexico, adjacent to Baca County, Colorado. One subspecies, Myotis thysanodes thysanodes, occurs in Colorado. ~scriptien The fringed myotis apparently is not particularly abundant in Colorado. It is found in ponderosa pine woodlands, greasewood, oakbrush, and saltbush o1git1zed by Goog le

3 shrublands. In the Pacific Northwest 93 percent of day roosts were in ponderosa pine; "snag" trees were used infrequently (only 5 percent of roosts located; Lacki and Baker 2007). However, in northern California, Douglas-fir snags in early to medium states of decay were used frequently, accommodating up to 88 individuals (Weller and Zabel 2001 ). In the Black Hills of South Dakota, the fringed myotis roosted in rock crevices as well as trees (Cryan et al. 2001). These bats may begin to forage shortly after sunset, although most of their activity occurs within 2 hours after dark. As with some other bats, moderate precipitation does not much influence activity. Gleaners, they forage close to the canopy, where they pick prey insects off the vegetation during a slow maneuverable flight. The fringed myotis has a relatively broad diet, feeding on moths, beetles, caddisflies, hymenopterans (ants, bees, and wasps), and other insects (G. Freeman 1984). D1git1zed by Goog le

4 '0 10 &?00 1g MAP Distribution of the fringed myotis (Myotis thysanodes) in North America. o1git1zed by Goog le

5 --- 0 U) M JB 40 5(} Miles MAP Distribution of the fringed myotis (Myotis thysanodes) in Colorado. Females mate in the fall and store sperm over winter, with ovulation and fertilization occurring in late April and May. The gestation period is days, with 1 young produced annually. Barbour and Davis (1969) captured pregnant fringed my otis near Colorado Springs in mid-june. Young are capable of flight by 2.5 weeks of age and by 3 weeks young are indistinguishable in size from adults. Nursery colonies of several hundred fringed myotis have been reported in other areas but records on distribution, behavior, and ecology of this species in Colorado are scarce. Caves, mines, and buildings are used as both day and night o1git1zed by Goog le

6 roosts. M. O'Farrell and Studier (1973) discussed maternity roosts of M thysanodes in northeastern New Mexico. Localized migrations are thought to occur, but firm data are lacking. Hibernation sites include caves and buildings. R. Adams and Hayes (2008) found that lactating fringed myotis visited waterholes 13 times more often than did non-lactating females. From their data they built a model that predicted serious impacts on these bats from a warming and drying climate. The literature on the fringed myotis was reviewed by M. O'Farrell and Studier (1980) and Keinath (2004). Myotis velifer CAVEMYOTIS Description The cave my otis, a species of possible occurrence in Colorado, is large for the genus, with pale brown dorsal pelage and a somewhat paler venter. The hair is of moderate length and coarse, has no sheen, and is often described as "woolly." This species may be confused with Myotis lucifugus or M yumanensis and is best distinguished by having a forearm longer than 41 mm, a condylobasal length greater than 16 mm, and a well-developed sagittal crest on the skull. Drscriptien The cave myotis has not been documented in Colorado, but it is likely to be found. It occurs at lower elevations in the Southwest (north and east to southcentral Kansas) and Mexico. Individuals of the Great Plains subspecies Myotis velifer grandis may occasionally enter southeastern Colorado. Caire et al. (1989) and Dalquest et al. (1990) reported captures in Cimarron County, Oklahoma, in the Panhandle within about 25 km of Colorado, and the westernmost record from Kansas (J. K. Jones, Fleharty, and Dunnigan 1967) is 140 km from the Colorado border. By contrast, the southwestern subspecies, M v. velifer, is D1git1zed by Goog le