Marine Mammal Unit

• Main Authors: Linda Nichol, John Ford, Graeme Ellis, Anna Hall
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Osborne; Pacific; Harbour porpoise
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.544.3368; http://www.pac.dfo-mpo.gc.ca/science/oceans/detroit-georgia-strait/documents/eri_0809_reports/nichol_s0fg eri small cetacean diet 200809l_nichol.pdf

Dall’s porpoise are abundant throughout their North Pacific range and harbour porpoise are widely distributed and locally common (Leatherwood et al. 1982; Osborne et al. 1988). Both species are commonly encountered in B.C. inshore waters. Incidental sightings, some systematic survey effort and strandings all indicate that both species are common in the Strait of Georgia and the Strait of Juan de Fuca (Calambokidis et al. 1997; Hall 2004; Keple 2002). Within this region, there seem to be seasonal shifts in distribution that may be associated with seasonally abundant or concentrated prey species (Halll 2004; Keple 2002). Small schooling fish and cephalopods generally comprised the diet of these porpoise species. However, little is known of the prey species consumed in the Strait of Georgia and Strait of Juan de Fuca (the study area of the Strait of Georgia Ecosystem Initiative). These cetaceans likely make a significant contribution to the ecosystem as upper trophic level taxa. To address these gaps in knowledge regarding the diet and ecosystem role of these porpoise species in the Strait of Georgia Ecosystem, we investigated diet by examining stomach contents. The stomach samples were obtained from stranded