FORT COLLINS, Colo. — Editor's Note: A previous version of this story did not accurately describe the way the bats may have died. The story has since been updated.
Three bats were killed at Colorado State University (CSU), violating federal law, according to a watchdog group.
National nonprofit Stop Animal Exploitation Now (SAEN) said government documents made public on Wednesday show the bats were run through an equipment sterilizer and has filed a federal complaint against CSU for negligence.
Sterilization in research facilities is achieved by washing items in temperatures high enough to kill most bacteria, meaning the bats were boiled alive, SAEN said in a statement.
The United States Department of Agriculture (USDA) said the report that SAEN is referencing says the bats actually died when they were accidentally folded in a shade cloth overnight.
The USDA said in a statement that: "The bats were members of a breeding colony maintained by the facility. To provide environmental enrichment for the animals, shade cloth is hung on the walls of the room that houses the breeding colony. For the health and well-being of the bats, the shade cloth is taken down on a routine schedule to be cleaned and sanitized. During this incident, after being taken down and folded, the shade cloth was taken to the cage wash room and left overnight to be washed the next day. When the shade cloth was unfolded the next morning to be cleaned, three perished bats were found inside the cloth."
CSU was issued a "critical" citation for violating federal law governing the treatment of research animals after government inspectors reported the deaths in the Jan. 28 report.
A reported 2018 incident involving the deaths of seven bats when their enclosure flooded is also included in the complaint. In that case, the report says the room flooded when a drain flush became stuck during routine cleaning.
The complaint, which includes relevant federal reports and correspondence, can be found on SAEN's website.
CSU paid a $23,000 federal fine in 2011 for previous Animal Welfare Act violations, according to SAEN.
CSU called the accusations "misleading and untrue" in a statement, and said the deaths were a mistake. The university said the breeding colony died when a dark colored cloth was removed from their habitat for cleaning.
"The person who removed the cloth did not see that three bats, which are small and weigh up to or less than an ounce, were attached to the cloth because both the cloth and the bats were dark in color," the university said.
The cloth was put in a laundry hamper with the bats attached, and they were discovered dead the next day before the cloth was laundered, according to CSU's statement.
CSU said the process has been changed to avoid future deaths.
The 2018 incident stems from an automatic shutoff failing in a facility, according to the university. CSU said a system that regularly flushed out bat waste down a floor drain malfunctioned, flooding the floor of a basement where the bats were kept with about 4-6 inches of water.
"It is unknown why seven bats were in the water and unable to fly out of the water onto their roosting habitat in the room. The automated shut off was replaced with a manual shut off, and procedures were put in place."
The university said it immediately and voluntarily reported both incidents.
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