October 2024 - 21

hundreds of insects per hour, which for some
little brown bats can be 100 percent of their
body weight in one night.
Little brown bats and other similar species
are under attack by a disease that has killed
millions of bats in the eastern U.S. White-nose
syndrome is caused by a fungus that attacks
bats during hibernation, draining fat reserves
and causing death. In the face of this threat,
biologists like Beard are conducting monitoring
and research studies to help conserve
bat species across the country. However, these
animals can be challenging to study in the
West, as they don't gather in as large numbers
in the winter like eastern populations once did.
Their small size and nocturnal activity create
research and monitoring challenges, making
it difficult to get accurate population sizes
and document mortalities. However, there are
some solutions to studying these species, and
one strategy requires the use of summer roosts.
A roost is an area where animals like bats or
birds congregate to rest. Bats use roosts each
day to rest, but winter and summer roosts are
the most important, as they support critical
events in the bat's year. In the winter, many
species of bats use a roost called a hibernaculum.
As the name suggests, they use this type
of roost for hibernation, which allows them to
survive the long cold season without bugs to
eat. In the eastern U.S., large numbers of bats
gather in underground cavernous areas such as
caves or mines. Biologists in the western U.S.
cannot rely on these types of roosts because
western bats rarely use this type of hibernacula.
However, there is a second roost called a
maternity roost. Biologists rely on this type
of roost in the summer to monitor western
bats. Maternity roosts are warm areas found
in buildings, under tree bark, in rock crevices
or within a hollow tree where pregnant
female bats give birth and nurse their young.
Knowing where bat roosts are located helps
biologists understand population trends of
western bat species and track the spread of
white-nose syndrome.
Knowing how animals behave, reproduce
and live on the landscape is crucial to monitoring
and understanding how to support a
healthy population. Researchers rely on maternity
roosts to help provide accurate population
information. According to the Western Bat
Working Group, challenges such as climate
change, habitat loss, persecution, wind energy
development and white-nose syndrome all
impact bat conservation.
Bat technicians Britney Force and Adam Nash process bats when sampling for the fungus that causes white-nose syndrome.
(Photo by Julia Yearout/WGFD)
MONITORING METHODS
Game and Fish uses several types of monitoring
to understand bat distribution, populations
and trends in the state. These include hibernaculum
counts, maternity roost counts, recording
bat sounds and bat captures. Repeated roost
surveys at known maternity roosts are vital
to population monitoring and can help biologists
address the conservation needs of bats
in Wyoming and the Rocky Mountain West.
Knowing the locations of established maternity
roosts helps with the collection and analysis
of population data.
In addition to population counts across
Wyoming, getting a pulse on the impacts
of white-nose syndrome is key for bat
conservation.
" White-nose syndrome is a disease caused by
an introduced fungal pathogen called Pseudogymnoascus
destructans or Pd, that attacks bats
when their immune systems are depressed
during hibernation, " Beard said.
Sometimes Pd looks like white fuzz on a
bat's face, and that is how the disease got its
name. It attacks the bare skin of bats while
Wyoming Wildlife | 21

October 2024

Table of Contents for the Digital Edition of October 2024