138 
Mary Kay Clark and David S. Lee 
and found several P. townsendii present at that time. Both caves are 
close to the 1524-m elevation contour and in a transition zone between a 
hardwood and a spruce-fir forest. Unlike most other caves inhabited by 
Plecotus in the East, these caves are formed in Montezuma Schist 
(Grandfather Mountain formation) rather than Greenbrier Limestone. 
In North Carolina, Montezuma Schist is restricted to small areas in 
Avery and adjacent counties, and this formation is the southermost site 
of volcanic rocks of the late Precambarin in the Blue Ridge. 
Subsequently we learned that Sturgis McKeever had collected two 
Plecotus in a rock outcropping near the previously mentioned Avery 
County caves on 22 September 1968. We examined the specimens, 
which are in McKeever’s private collection, and found them also to be 
P. t. virginianus . Thus, records of this bat have been obtained from four 
North Carolina sites (three in extremely close proximity) over a period 
of nearly 20 years and from both sides of the Eastern Continental 
Divide. 
Our visits to the Avery County sites in March, June, July, August, 
and September and reports by cavers of big-eared bats in these same 
caves in November and January indicate that the bats are present 
throughout the year. Apparently they are few in number; we have never 
encountered more than 20 on a single visit, although Currie reported to 
us the presence of more than 60 bats in one cave in 1986. The Avery 
County caves have multiple entrances that allow enough turnover of air 
to produce the low temperatures necessary for hibernation. Because of 
the high elevation of the caves, summer cave temperatures are appar- 
ently too cool for summering bats or maternity colonies. We were 
unable to locate bats of any species in these caves in July and August. 
Mist-netting at the entrances, however, showed that modest numbers of 
Plecotus were visiting the caves after dark during these months; so we 
suspect there is at least one other Plecotus cave in the immediate vicin- 
ity. All bats netted in summer were caught as they entered the cave. In 
netting these bats we actually captured and handled only a few, but 
perhaps as many as a dozen were seen on each of several nights during a 
1-hour period. On 29 September 1984 a juvenile with an attendant 
female was found in a group of 10 to 20 bats roosting in one Avery 
County cave. Late in the afternoon of 11 July 1984, Clark accidently 
startled a roosting Plecotus from a rhododendron, Rhodo- 
dendron catawbiense, near a cave entrance. The bat flew directly into 
the cave. 
Plecotus began roosting in the high-elevation Avery County caves 
as early as early September and remained in them until at least late 
March. Within the caves the bats used several distinct roosting sites, one 
in the twilight zone and others high in the back part of the cave; several 
roosted in side passages. Roosting sites appear to shift with changing air 
temperatures, and perhaps also with human disturbance. Main-passage 
cave temperatures during our visits varied from 0 °C (March) to 13 °C 
