O’SHEA, CRYAN & BOGAN: UNITED STATES BAT SPECIES OF CONCERN 
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roof of a shallow, 14- to 15-meter high grotto in a 100 meters high cliff in southeastern Arizona; 
a group of 90-100 occupied a roost in a crevice opening 20 meters high in the roof of a second 
shallow grotto in a 100 meters high cliff in northwestern Arizona (Cockrum, 1960; Cox, 1965; 
Cockrum et al., 1996). From two to four individuals also were seen emerging from a crevice in the 
roof of a cave that housed cliff dwellings at Tonto National Monument in Gila County in south- 
central Arizona during 1962 (Johnson and Johnson, 1964). General daytime locations of roosts of 
three adult females radio tagged on the Kaibab National Forest in northern Arizona were in Sono¬ 
ran Desert habitat (about 600-880 meters elevation), within inaccessible high cliffs along the rim 
of the Grand Canyon, 28-29 kilometers from the points where the bats were captured over ponds 
in subalpine forest at 1,900-2,400 meters elevation (Siders et ah, 1999). One of the radio-tagged 
individuals was tracked to a tall ponderosa pine tree for a single night before moving to a roost at 
an unknown location within the Grand Canyon (Siders et ah, 1999). 
Greater bonneted bats are also known to roost in attics and buildings, particularly in crevice¬ 
like spaces, and historically were reported from such places near Los Angeles, California (Howell, 
1920b, von Bloeker, 1932; Krutzch, 1955; Leitner, 1966; Couffer, 1992). Reproduction occurred in 
these buildings, including a maternity colony with 25 young described inhabiting the attic of a three 
story building in Covina, Los Angeles County, California (Howell and Little, 1924). They also have 
been observed in or near other cities, including Tucson, Arizona, Las Vegas, Nevada, and Mexico 
City, Mexico (Cockrum, 1960; Bradley and O’Farrell, 1967; Avila-Flores and Fenton, 2005). Night 
roosting of solitary individuals has been observed (Krutzsch, 1955). 
Population Ecology.— Litter Size, Natality, and Female Reproduction: Hilda Grinnell 
(1918) recorded single embryos in each of three adult females examined in southern California. 
Howell (1920b) reported single embryos in each of 13 females taken in southern California, as did 
Krutzsch (1955) based on notes of others on an unspecified number of females. However, Krutzsch 
(1955) also directly observed one female with two embryos and four with one embryo each. One 
female from southern Arizona was observed giving birth to a single young in the field (Cockrum, 
1955, 1960). Two females with single embryos were collected in Capote Canyon in southwestern 
Texas (Ohlendorf, 1972), and single embryos were found in each of 6 pregnant females examined 
at Big Bend National Park in Texas, where natality was 56% (20 of 36 adult females captured over 
water were reproductive; Easterla, 1973). Six of eight females captured over water near the Grand 
Canyon in northern Arizona were lactating (Siders et al., 1999). In northwestern Arizona, each of 
four adult females taken at a maternity roost was lactating (Cockrum, 1960). Birth occurs once 
annually during warm months but timing is otherwise asynchronous within a colony (Krutzsch, 
1955). We are unaware of any published literature with quantitative data concerning other demo¬ 
graphic aspects of female reproduction, such as age at first reproduction and inter-birth intervals. 
Survival: We are unaware of any published literature with quantitative data on survival for 
this species. 
Mortality Factors: Little is known about causes of mortality in greater bonneted bats. Deaths 
due to rabies have been documented (for example, Constantine et al., 1979; Constantine, 1979, 
1988; Caire and Loucks, 2013). A peregrine falcon was observed preying on a greater bonneted bat 
released during daylight (Easterla, 1973). Ectoparasites are known (for example, Krutzch, 1955) 
but no associated mortality has been reported. 
Population Trend: Howell (1920b:111) stated: “I have no hesitancy in pronouncing it a com¬ 
mon species in the orange section or thermal belt of Los Angeles County. However, to be success¬ 
ful in finding it, one must employ no little energy and perseverance.” Other than the work of 
Dalquest (1946), Krutzsch (1955), and Vaughan (1959), few such efforts were employed in Cali¬ 
fornia until the early 1990s, when previously known roosting areas and likely sites throughout Cal- 
