Abstract

Wildlife field studies provide valuable information about animal behavior, natural history, and health. However, capture techniques and the procedures associated with tagging and sample collection have the potential to cause temporary pain and distress. Mitigation of these stress-related physiological alterations through sedation and handling techniques is of high practical importance when working with animals in the field setting. The purpose of this paper is to describe safe and efficient handling and sedation techniques used in arctic and sub-arctic phocid species in order to collect biological samples and apply tracking instruments. From 2006–2016, 317 ribbon seals (Histriophoca fasciata), spotted seals (Phoca largha), harbor seals (Phoca vitulina) and bearded seals (Erignathus barbatus) were captured as part of a variety of field projects. Of the seals captured, 152 (48%) were sedated with either diazepam or midazolam. Diazepam was administered intravenously for ribbon (mean 0.12 mg/kg) and spotted seals (mean 0.13 mg/kg) due to the rapidity and predictability of effects and because animal size and handling practices enabled consistent IV access. Bearded seals received midazolam at a mean dose of 0.16 mg/kg, IM. Harbor seals were initially administered midazolam at a mean dose of 0.18 mg/kg IM. Bearded seals and harbor seals were often given a second IV dose of either diazepam or midazolam (0.11–0.14 mg/kg) in order to complete the procedure. Sedation was reversed with flumazenil administered a dose of 0.003–0.01 mg/kg. Doxapram was given to ribbon seals orally and IV to counteract capture related apnea. Capture and administration with diazepam and midazolam provided safe and reliable sedation for free-ranging Arctic and sub-Arctic Alaskan phocids, and allowed the scientific team to safely collect data and apply tags while minimizing animal distress.

* Presenting author