Little Brown Bats (image) Ecological Society of America Share Print E-Mail Caption Pregnant little brown bats huddle together in "maternity colonies" to conserve warmth, as they are unable to regulate their body temperature. Credit Photo courtesy of NPS. Usage Restrictions Photo courtesy of NPS. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.