Bats Blog Posts

On one memorable nighttime visit to Redwood Creek in Muir Woods, I met with several National Park Service and US Geological Survey biologists to learn about and photograph their bat research. Turns out it’s a good place to catch bats that like to hunt along the creek for mosquitos, flies, and beetles. In the last few moments of sunlight, we set up four mist nets (loose, nearly invisible mesh nets) over different parts of the creek and crossed our fingers.

Through acoustic monitoring, winter mist netting, and summer radio telemetry, researchers have started to describe Bay Area bats’ habitat preferences, roosting sites, and more. But there’s a whole other black hole of bat knowledge that they’re just now beginning to peer into: bat migrations. This fall, the team started leveraging an automated wildlife tracking system for the first time to better understand bats’ journeys as they migrate through—and beyond—local parks.

After a long hiatus due to concerns of the unknown risk of transferring COVID-19 from humans to bats, the Marin Bat Monitoring Project team was finally able to safely resume the bat-handling portion of our research this summer.

In 2017, biologists at Pinnacles National Park began to systematically track resident bats via mist netting and acoustic monitoring. Mist netting was a no-go this year due to the coronavirus. However from July 13-17, biologists did deploy acoustic bat detectors at four sites throughout the park for a fourth year in a row.

Since 2017, One Tam partners have been collaborating with USGS to conduct the first countywide bat monitoring program in Marin. This October, we dove in to the results from last winter's roost site monitoring, and discussed the implications of what park researchers have learned from three years of bat monitoring.

Coronaviruses exist in many mammals and birds all across the globe. At the USGS National Wildlife Health Center (NWHC), wildlife scientists are doing their part to tackle questions about COVID-19 and wildlife. For example, could North American wildlife become reservoirs of SARS-CoV-2, the virus behind COVID-19? What species are most susceptible? What can we do to reduce the risk of spreading the virus to wildlife?

Since 2017, One Tam partners have been collaborating with USGS to conduct the first countywide bat monitoring program in Marin. One piece of the program is roost site monitoring, which begins with mist netting to catch bats. This past February, the monitoring team spent seven nights mist netting at Cascade Canyon and near Lake Lagunitas on Marin Municipal Water District land.

Few individuals have shaped our understanding of terrestrial species in the San Francisco Bay Area and California national parks like Dr. Gary Fellers, who passed away in November. Gary worked at Point Reyes National Seashore from 1983 until his retirement in 2013, first as a National Park Service scientist, and later as a researcher for the USGS Western Ecological Research Center.

The current biggest threat to Bay Area bats are habitat loss and disturbances to the places where they roost. As a result, researchers in Marin County are hoping to check which bat species are present, and learn more about their roosting habits and how they use local habitats. Such information could also help us understand how susceptible local bats are to White-nose Syndrome, and how best to protect them in the event that the fungal disease spreads to the Bay Area.

It began near Albany, New York in 2006 when cavers captured the first glimpses of bats with a fuzzy white fungus growing on their muzzles. Since then, white-nose syndrome has spread out from NY in all directions, decimating hibernating colonies of many bat species. In 2016, it was confirmed for the first time in a western state (Washington), more than 1,300 miles from the previous western frontier of the disease. Now, the fungus that causes it has been found in California.