Huggins J.L.,Collective |
Raverty S.A.,Animal Health Center |
Norman S.A.,Central Puget Sound Marine Mammal Stranding Network |
Norman S.A.,Marine Med Marine Research |
And 10 more authors.
Diseases of Aquatic Organisms | Year: 2015
In 2006, a marked increase in harbor porpoise Phocoena phocoena strandings were reported in the Pacific Northwest of the USA, resulting in the declaration of an unusual mortality event (UME) for Washington and Oregon to facilitate investigation into potential causes. The UME was in place during all of 2006 and 2007, and a total of 114 porpoises stranded during this period. Responders examined 95 porpoises; of these, detailed necropsies were conducted on 75 animals. Here we review the findings related to this event and how these compared to the years immediately before and after the UME. Relatively equal numbers among sexes and age classes were represented, and mortalities were attributed to a variety of specific causes, most of which were categorized as trauma or infectious disease. Continued monitoring of strandings during 4 yr following the UME showed no decrease in occurrence. The lack of a single major cause of mortality or evidence of a significant change or event, combined with high levels of strandings over several post-UME years, demonstrated that this was not an actual mortality event but was likely the result of a combination of factors, including: (1) a growing population of harbor porpoises; (2) expansion of harbor porpoises into previously sparsely populated areas in Washington's inland waters; and (3) a more well established stranding network that resulted in better reporting and response. This finding would not have been possible without the integrated response and investigation undertaken by the stranding network. © Inter-Research 2015.
Norman S.A.,University of California at Davis |
Huggins J.,Cascadia Research Collective |
Carpenter T.E.,University of California at Davis |
Case J.T.,University of California at Davis |
And 9 more authors.
Marine Mammal Science | Year: 2012
In 2006-2007, an unusually high number of harbor porpoises (Phocoena phocoena) stranded along the Washington and Oregon coastlines. Spatiotemporal analyses were used to examine their ability to detect clusters of porpoise strandings during an unusual mortality event (UME) in the Pacific Northwest using stranding location data. Strandings were evaluated as two separate populations, outer coast and inland waters. The presence of global clustering was evaluated using the Knox spatiotemporal test, and the presence of local clusters was investigated using a spatiotemporal scan statistic (space-time permutation). There was evidence of global clustering, but no local clustering, supporting the hypothesis that strandings were due to more varied etiologies instead of localized causes. Further analyses at subregional levels, and concurrently assessing environmental factors, might reveal additional geographic distribution patterns. This article describes the spatial analytical tools applied in this study and how they can help elucidate the spatiotemporal epidemiology of other UMEs and assist in determining their causes. More than one spatial analytical technique should be used if the study objective is to detect and describe clustering in time and space and to generate hypotheses regarding causation of marine mammal disease and stranding events. © 2011 by the Society for Marine Mammalogy.
Norman S.A.,Marine Med Marine Research |
Garner M.M.,Northwest ZooPath |
Berta S.,Central Puget Sound Marine Mammal Stranding Network |
Dubpernell S.,Central Puget Sound Marine Mammal Stranding Network |
Klope M.,Central Puget Sound Marine Mammal Stranding Network
Journal of Zoo and Wildlife Medicine | Year: 2011
A large number of vaginal calculi were observed in a juvenile harbor porpoise (Phocoena phocoena) stranded on Whidbey Island, Washington. Vaginal calculi have been reported in other species, but not in harbor porpoises. Histologic examination of the urinary tract revealed mucosal hyperplasia most likely attributable to the calculi. The calculi were numerous (>30), composed completely of struvite (magnesium ammonium phosphate), and on culture yielded Enterococcus spp., a bacterium not usually associated with struvite urolith formation in domestic animals. The only other lesion of note was severe hepatic lipidosis, and its relationship to the development of the vaginal calculi is unknown. Copyright 2011 by American Association of Zoo Veterinarians.