State of the Bats Report

The hoary bat (Lasiurus cinereus) knows no boundaries or borders. Still, it is one of 82 bat species—more than half of the 154 bat species on the North American continent—at risk for severe population declines over the next 15 years, according to the first-ever North American State of the Bats Report.

The report, a monumental tri-national survey generated by the North American Bat Conservation Alliance (NABCA), compiles research from 102 bat experts across Canada, the United States, and Mexico to establish a baseline of data to measure the success of bat conservation and encourage collaboration. Moreover, it presents a united message that bats need help now to avoid catastrophic conditions later.

The hoary bat is one of 154 reasons the report was compiled and a good example of the complex challenges of bat conservation between three countries, according to Dr. Jordie Segers, Canadian National Bat Health Program Coordinator for the Canadian Wildlife Health Cooperative. It’s important to note that some bat species face different challenges in different locations.

“Hoary bats are one of several migratory bat species that cross international borders between Canada, the U.S., and Mexico. In all countries, we’re seeing this species, along with eastern red bats and silver-haired bats, fatally impacted by the rotating blades of wind energy turbines,” says Dr. Segers.

“The State of the Bats Report identifies rapid growth in the wind energy sector on both sides of the border and unites us in identifying this as a threat to find solutions,” he says. “Wind energy is important as a renewable energy source and can, when managed appropriately, coexist with bats. It’s why cross-border collaboration and research is essential to protect these bat species from harm.”

“The Mexican free-tailed bat (Tadarida brasiliensis) is a species that highlights the importance of reciprocal collaboration between Mexico and the U.S.,” says Dr. Rodrigo Medellin, Senior Professor of Ecology at National Autonomous University of Mexico and co-chair of NABCA.

Dr. Medellin says that free-tailed bats are vital to U.S. and Mexican agriculture crops such as corn, cotton, rice, beans, chiles, and others since they devour and control insect pests.

“The services that this migratory species provides to the U.S. depends on the conservation of overwintering colonies in Mexico,” Dr. Medellin says. “Likewise, the benefits the bats provide in Mexico depend on the conservation of their breeding colonies in the U.S. during summer months. The species would be doomed if both countries did not join forces to secure its future across North America.”

Dr. Medellin also points to the collaborative success in recovering lesser long-nosed bats (Leptonycteris yerbabuenae) as a case study in collaboration. He recounts traveling in the mid-’80s through central and northern Mexico with Dr. Don Wilson from the Smithsonian Institution to known roosts of the lesser long-nosed bat and being shocked to find empty and near-empty roosts. That trip motivated the group, he says, to propose listing this species under the provisions of the U.S. Endangered Species Act in 1988 and the Mexican Federal List of Endangered Species in 1994.

“The major threat was vandalism of roosts, so we started a strong environmental education campaign that changed the attitudes of many people, primarily landowners near the main roosts of the species. This ultimately led to the recovery and delisting of the species in 2013 in Mexico and 2018 in the U.S.,” Medellin says. “The most important part of the State of Bats Report is that it represents collaboration.”

In the subarctic climate near Yellowknife in the Northwest Territories of Canada, one species, the little brown myotis (Myotis lucifugus), thrives. Far to the south, across nearly 5,000 miles of North America’s exceptionally diverse landscape, in the balmy and tropical climate of the southernmost reaches of Mexico, dozens of bat species thrive, including the southern yellow bat (Lasiurus ega). One of the wonders of bats is their species diversity and the vital place they hold in healthy, biodiverse ecosystems.

“Coordinating input with all the top bat experts across North America was a major feat, but proved vital for building consensus about the major threats to bat species and identifying the knowledge gaps that we need to fill to advance conservation efforts,” says Dr. Amanda Adams, Bat Conservation International’s (BCI) Director of Research Coordination. Dr. Adams served as the BCI lead on the State of Bats Report, working with members of the NABCA board; communicating with 102 bat experts; participating in unfathomable numbers of Zoom meetings; and shaping a 12-page summary of the findings into a compelling report.

“Our goal was to create a baseline for future Status and Trends Reports created with data contributed to the North American Bat Monitoring Program (NABat),” says Dr. Adams. “Technological advances, willingness to form partnerships across borders, and the dire need to document the decline of bats on this continent allow us to move into a new age of bat conservation.”

For example, Dr. Adams points to how acoustic monitoring has advanced bat research and the ability to share research.

“Fifteen years ago, the ability to record and analyze bat calls was expensive and cumbersome. Then, I might go into the field with one detector and worry about having enough digital storage to record one night of calls,” she says. “Today, we don’t have those constraints. Monitoring has become ubiquitous. We now have millions of recordings from across the country that can be used to inform us of the status of bat populations. The true power of this data to information conservation comes through the vast collaboration of agencies and people contributing this data to the NABat monitoring program.”

Climate changes—severe droughts that dry up water sources, wildfires that damage habitats, and wide-ranging temperature extremes that disrupt mating and migration—are among the major threats identified in the report. Some of the other threats include land management decisions that degrade or destroy roosts and foraging areas; mortality caused by unmanaged wind turbines; and white-nose syndrome, a deadly fungal disease that has already decimated more than 90% of three hibernating bat species found in the U.S. and Canada.

The challenge is reaching more people with this information to advocate for bats. One of the most significant goals of the State of Bats Report is to get more people engaged in bat conservation, according to Dr. Adams.

The report is intended to demystify bats. “People tend to relate to bats—or not—depending on where they live and what they have experienced,” says Dr. Adams. She mentions that sometimes people are surprised to learn that bats live in their area, while others—who may see bats in their backyards—may understand them better. People who have witnessed huge bat colonies may have even different views. “It’s safe to say that people have a better understanding of bats after they have witnessed bat flights at Bracken Cave or Congress Ave. in Austin or other locations,” Dr. Adams says.

“Bats face many challenges today, and the conservation landscape is increasingly complex,” says Dr. Jeremy Coleman, National White-nose Syndrome Coordinator for the U.S. Fish and Wildlife Service and Co-chair of NABCA. “While there is more to do, the level of international collaboration we have achieved for bat conservation in North America, with the publication of this report, is a bright spot and a cause for optimism going forward.”

“As the scope and severity of these threats increase, so does the risk of losing some species forever,” says Dr. Winifred Frick, BCI’s Chief Scientist. “Conservation projects can make the difference between life or death for bats. People working together, from government agencies to bat enthusiasts, are important players to ensure bats have the attention and protections they need to survive and prosper.”

“The message of the report comes down to this: We need bats, and bats need us. It’s a phrase my 13-year-old son came up with. Getting kids involved and galvanizing our community to participate in bat conservation is our path forward to help bats and help ourselves,” Dr. Frick says.