An Unusual Mortality Event of Harbor Porpoises (Phocoena phocoena) Off Central California: Increase in Blunt Trauma Rather Than an Epizootic

作者:Wilkin Sarah M*; Cordaro Joe; Gulland Frances M D; Wheeler Elizabeth; Dunkin Robin; Sigler Teri; Casper Dave; Berman Michelle; Flannery Moe; Fire Spencer; Wang Zhihong; Colegrove Kathleen; Baker Jason
来源:Aquatic Mammals, 2012, 38(3): 301-310.
DOI:10.1578/AM.38.3.2012.301

摘要

In 2007, the apparent increase in the number of harbor porpoises (Phocoena phocoena) stranding along the central California coast compared to the number of strandings the previous year resulted in the declaration of an Unusual Mortality Event by the National Marine Fisheries Service. A statistically significant increase in strandings occurred in 2008 and 2009, with more than twice the mean annual number of strandings documented per year in the previous decade occurring each year, but then strandings decreased in 2010. No single cause of mortality explained all the strandings, and there were no significant changes in age class or sex of strandings in 2008 and 2009. Trauma, including interspecific aggression and fisheries interactions, was the most common cause of death, and blunt force trauma increased significantly in August through October of 2008 and 2009. Domoic acid toxicosis was documented for the first time in this species. Although the cause of death for many strandings was unidentified, the increase in strandings in 2008-2009 reflects an increase in blunt trauma rather than an epizootic of disease.

  • 出版日期2012