First Thirty Days of Life: Examining Calf Behavioral Development in Beluga Whales ( Delphinapterus leucas ) and Pacific White-Sided Dolphins ( Lagenorhyncus obliquidens ) at One Zoological Facility

• Main Author: Smith, Kendal
• Format: Text
• Language: unknown
• Published: The Aquila Digital Community 2019
• Subjects: development; marine mammal; marine mammal behavior; beluga whale; dolphin; marine mammal development; Animal Studies; Biological Psychology; Comparative Psychology; Developmental Psychology; Other Psychology; Pacific; Beluga; Beluga whale; Beluga*; Delphinapterus leucas
• Online Access: https://aquila.usm.edu/masters_theses/606; https://aquila.usm.edu/context/masters_theses/article/1476/viewcontent/auto_convert.pdf

Cetacean development is important for general comparative understanding and the implementation of informed husbandry policies. Due to the inaccessibility of many of these species in the wild, researchers can study managed care populations to better understand basic developmental patterns of cetaceans, as well as to improve husbandry policies for facility animals. However, no previous studies have attempted to observe the behavioral development of Pacific white-sided dolphins (Lagenorhyncus obliquidens). Eight beluga whale calves and four Pacific white-sided dolphin calves were observed for the first 30 days of life to determine the developmental trajectory of several typically monitored behaviors. The first occurrence and developmental trajectory for each behavior are described to identify variation and to document differences between successful calves, those that survived the 30-day period, and unsuccessful calves, those that did not survive the 30-day period, of both species. A single-case time series design analyzed developmental pattern differences within the 30 days for the successful calves. Overall, beluga whales and Pacific white-sided dolphins exhibited similar developmental trends; however, beluga whale calves had significantly higher nursing duration and frequency and rates of slipstream position than Pacific white-sided dolphin calves. Nursing behaviors and slipstream behaviors of the unsuccessful calves of both species were either inconsistent or delayed compared to the successful calves. The results of this study may be used to better understand norms of cetacean development and to stimulate future research in the early identification of abnormal development in the hopes of increasing calf survival rates.