Marine mammals face special challenges at night and while sleeping during the day. Given the difficulties of studying natural behavior, there are few studies of nighttime behavior in marine mammals. I have some personal experience with around-the-clock care in rescue situations but would like to poll the list for any favorite publications, notes or personal experiences you've had with nighttime behavior in cetaceans or sirenians. I'll share back to the list what I learn. Cordially yours, Geoff Patton, Ph.D. Silver Spring, MD