Alternative Energy Draft EA - NASA Visitor Center at Wallops Flight ...

Affected Environment
Over the entire study period, the majority of calls (55.2 percent) were identified as “unknown.”
Of these unknown sequences, sequences likely to be eastern red bats or eastern pipistrelles were
most common (44.9 percent). The majority of call sequences could not be identified to guild or
species, however, due to short call sequences (less than five pulses) or poor call signature
formation, which were often a result of bats flying at the edge of the detection zone of the
detector or flying away from the microphone.
Of the calls that were identified to species or guild, those of the RBEP guild were the most
common (27.9 percent), followed by the species within the BBSH guild (15.7 percent), hoary bat
guild (0.8 percent), and Myotid guild (0.3 percent).
Within the RBEP guild, eastern red bats accounted for 25.2 percent of the 2,140 total sequences
recorded at Wallops Island, followed by sequences just as likely belonging to red bats or eastern
pipistrelles (2.5 percent) and eastern pipistrelles (0.1 percent). Within the BBSH guild, sequences
just as likely belonging to big brown or silver-haired bats accounted for 10.8 percent of the total
sequences recorded, followed by those of big brown (4.4 percent) and silver-haired bats (0.5
percent).
Considering the level of bat activity documented at Wallops Island, numbers of recorded bat call
sequences are not necessarily correlated with number of bats in an area. Acoustic detectors do
not allow for differentiation between a single bat making multiple passes and multiple bats each
recorded a single time. Similarly, acoustic interference can make detection of bats in certain
areas difficult, lowering the estimate of acoustic activity.
Furthermore, calls of some bats, such as Rafinesque’s big-eared bat, are not as detectable as calls
of other bats, limiting the inferences that can be made about the presence or absence of listed
species. Rafinesque’s big-eared bat is the only special status species (State-endangered) likely to
occur in the region of Wallops Island and surrounding counties (BCI, 2001). Although no call
sequences likely belonging to Rafinesque’s big-eared bats were detected, the bat’s distribution
range overlaps Wallops Island, which may provide suitable habitat (VDGIF, 2009). However,
roosting and foraging data for this species are lacking (BCI, 2001). The 2008 summer-fall bat
survey can neither confirm nor exclude the presence of Rafinesque’s big-eared bat in the study
area.
3.2.4 Threatened and Endangered Species
Under Section 7 of the ESA, as amended, (U.S.C. 1531–1544) Federal agencies, in consultation
with the USFWS and the National Marine Fisheries Service (NMFS), are required to evaluate the
effects of their actions on special status species of fish, wildlife, and plants, and their habitats,
and to take steps to conserve and protect these species. Special status species are defined as
plants or animals that are candidates for, proposed as, or listed as sensitive, threatened, or
endangered by USFWS.
The Virginia Endangered Species Act (29 VAC 29.1-563–570) is administered by the Virginia
Department of Game and Inland Fisheries (VDGIF) and prohibits the taking, transportation,
processing, sale, or offer for sale of any State or federally listed threatened or endangered
species. As a Federal agency, NASA voluntarily complies with Virginia’s Endangered Species
Act.
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