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PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES 
Series 4, Volume 65, Supplement I 
western Oklahoma foraged while dispersing down canyons primarily at six to 15 meters above 
short stream vegetation or above taller cottonwoods at 15-30 m; most foraging episodes consisted 
of dipping and darting from side to side while flying in eight by 45 meters oval flight paths (Caire 
et al., 1984). In Kansas, cave myotis were reported to feed over high prairies at dusk, later moving 
down to river valleys (Hibbard, 1934). Individuals from colonies observed in the Riverside Moun¬ 
tains of southern California appeared to forage mainly over the floodplain of the Colorado River, 
utilizing dense linear stands of catclaw acacia, mesquite, tamarisk, and screw-bean bordering 
oxbows as well as scattered thick patches of vegetation elsewhere, often feeding within a few cen¬ 
timeters of the foliage and in small spaces between plants (Vaughan, 1959). 
This species has been described as an opportunistic feeder in south-central Kansas, where bee¬ 
tles were the major prey (37% of food items), followed by homopterans (18%), dipterans (14%), 
and lepidopterans (12%); size of prey varied from less than four to 20 millimeters (Kunz, 1974). 
Opportunistic feeding also was observed in central Arizona, where these bats foraged on ephemer¬ 
al swarms of flying ants {Pogonomyrmex sp.; Vaughan, 1980). In southern Arizona, they primari¬ 
ly consumed microlepidopterans, but at certain times weevils taken over agricultural fields formed 
the bulk of the diet (Hayward, 1970). Microlepidopterans about 10 millimeters in length were the 
predominant items found in stomach contents of 15 of 22 specimens from Arizona and Sonora, 
although small (four to 13 millimeters) beetles and weevils, dipterans, cicadellids, and neuropter- 
ans were also found (Ross, 1964, 1967). Food habits of adult females roosting in two caves and 
three bams during summer 2004 in the Red Hills of southern Kansas apparently did not differ 
between the two roost types, despite likely differences in thermal environments and consequent 
energetic requirements (Marquardt and Choate, 2009). The primary prey species in decreasing pro¬ 
portional volume were coleopterans (particularly scarabaeids), lepidopterans, dipterans, and 
hemipterans (Marquardt and Choate, 2009), similar to earlier findings of Kunz (1974). 
Roosting Habits. — Cave myotis are colonial, and roost in caves, old mines, and culverts, as 
well as in bridges and occasionally buildings (Grinnell, 1914; Hoffmeister and Goodpaster, 1954; 
Constantine, 1961a; Hayward, 1963, 1970; Anderson, 1972; Kunz, 1973). They often retreat into 
cracks and crevices within roosting sites. 
Winter Roosts: Studies of cave myotis in winter hibemacula have taken place in caves of cen¬ 
tral Kansas, northwestern Oklahoma, and northwestern Texas, some of which also may be used as 
summer colony sites (Twente 1955a,b; Tinkle and Milstead, 1960; Tinkle and Patterson, 1965; 
Dunnigan and Fitch, 1967; Caire and Loucks, 2010; Humphrey and Oli, 2015). In northwestern 
Texas during 1957-1963, they hibernated in multiple caves in colonies of about 1,000 to 5,000 
individuals at locations within 100 kilometers of their maternity colonies (Tinkle and Patterson, 
1965). Hibernating bats had fidelity to the cave where originally banded (80% of recoveries) or 
groups of caves within a local area (17%), with few making longer movements to other areas with 
hibemacula: less than 2% of over 10,000 banded bats made such major movements, averaging 89 
kilometers with a maximum of 145 kilometers (Tinkle and Patterson, 1965). Local movements 
among caves within eight kilometers of each other within winters were commonly observed, 
thought to be due to changing conditions of temperature, humidity, and air currents (although dis¬ 
turbance by investigators may also have been a factor). Within caves, bats frequently changed posi¬ 
tions during winter and moved among clusters on ceilings as well as to positions within groups in 
deep crevices; thermal regimes were cool and less fluctuating in these crevices, and groups of bats 
tended to be more stable in composition within crevices than on ceilings (Tinkle and Patterson, 
1965). Caves with coldest temperatures and highest levels of humidity were generally favored as 
hibemacula. Estimates as high as 46,700 hibernating bats were reported in one cave in northwest¬ 
ern Texas during 1960 (Tinkle and Patterson, 1965). Although peak counts are variable, the Selman 
