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Stewart J.S.,Stanford University | Gilly W.F.,Stanford University | Field J.C.,SWFSC NMFS NOAA | Payne J.C.,Vancouver Aquarium Marine Science Center
Deep-Sea Research Part II: Topical Studies in Oceanography | Year: 2013

Jumbo squid (Dosidicus gigas) have greatly extended their range in the California Current System, where they forage on a variety of ecologically and economically important species that inhabit both coastal and offshore mesopelagic regions. Swimming abilities and behavior are important factors in assessing the impacts of this range expansion, particularly in regard to foraging in conjunction with onshore-offshore movement over the continental shelf. Here we describe a study of horizontal movements by jumbo squid along and across the continental shelf off Washington, USA, using acoustic tags in association with the Census of Marine Life's Pacific Ocean Shelf Tracking Program (POST) receiver arrays. We detected frequent movements along the shelf break, movement onto the shelf at night, and no evidence of movement as a cohesive school. Our results demonstrate feasibility of using acoustic tags and arrays to document horizontal movements of jumbo squid along and across the continental shelf. This is important in order to determine how those movements overlap with those of other ecologically and commercially important fish species. © 2012 Elsevier Ltd. Source

Yunker M.B.,7137 Wallace Dr. | Macdonald R.W.,Canadian Department of Fisheries and Oceans | Ross P.S.,Vancouver Aquarium Marine Science Center | Johannessen S.C.,Canadian Department of Fisheries and Oceans | Dangerfield N.,Canadian Department of Fisheries and Oceans
Organic Geochemistry | Year: 2015

Marine coastal areas of British Columbia, Canada are subject to a gradient of increasing anthropogenic sources from pristine areas in the north to the more urbanised areas of the south. Along the gradient, the relative contributions of polycyclic aromatic hydrocarbons (PAHs) from multiple natural and anthropogenic sources are not well understood, but concerns linger about bioavailability and consequent risks to marine biota. Composition patterns and principal components analysis (PCA) models for surface sediment and core samples collected along this transect indicate that samples from the urbanised Vancouver area have the highest proportions of tricyclic terpane, hopane and sterane biomarkers, UCM (unresolved complex mixture), the alkyl fluoranthene/pyrene and benz[a]anthracene/chrysene series and most parent PAHs. Those from Hecate and Queen Charlotte Straits and other locations in the Strait of Georgia have, on the other hand, higher proportions of the resolved alkanes, and petrogenic alkyl naphthalene, fluorene, dibenzothiophene and phenanthrene/anthracene series. PAH ratios clearly indicate a predominance of combustion sources for the four ring and higher parent PAHs for all the sediments. Most samples have values close to the biomass/solid fuel and liquid fuel combustion borderline for ratios of the major PAHs, but liquid fuel combustion input dominates closer to urbanised locations. Ratios also suggest similar pyrogenic and petrogenic inputs between central Hecate Strait and reference sediments from Hecate Strait through to Queen Charlotte Strait, which indicates that biomass combustion and immature coal formations are the major putative respective sources for the reference areas. Alkyl PAH ratios for the C3 and C4 naphthalenes, C2 and C3 phenanthrenes and 3- and 2-methylchrysene, reflecting terrigenous/vascular plant sources and petroleum maturity, exhibit marked differences between Comox bituminous coal and Alberta Sweet Mixed Blend (ASMB) oil and reveal that the petrogenic input in all of the sediments is non-biodegraded. Ratios of these alkyl PAHs with multiple substituents indicate that the sediment samples in the northern Strait of Georgia closest to the Comox coal field receive relatively constant input of eroded coal, while those in the southern Strait of Georgia and Vancouver Harbour show a composition closest to ASMB oil. PAHs associated with liquid fossil fuel combustion and petroleum discharges adjacent to urbanised areas are expected to be fully bioavailable to marine food webs, while the char from biomass combustion and coal from immature deposits in more remote areas would have limited bioavailability. This implies that biota in remote areas of Hecate Strait/Queen Charlotte Sound are likely not adapted to the presence of oil and thus would be more sensitive to exposure to spilled oil than those in the more impacted environments in southern British Columbia. © 2015 Elsevier Ltd. Source

Filatova O.A.,Moscow State University | Ford J.K.B.,Canadian Department of Fisheries and Oceans | Matkin C.O.,Gulf | Barrett-Lennard L.G.,Vancouver Aquarium Marine Science Center | And 2 more authors.
Journal of the Acoustical Society of America | Year: 2012

Ultrasonic whistles were previously found in North Atlantic killer whales and were suggested to occur in eastern North Pacific killer whales based on the data from autonomous recorders. In this study ultrasonic whistles were found in the recordings from two encounters with the eastern North Pacific offshore ecotype killer whales and one encounter with the western North Pacific killer whales of unknown ecotype. All ultrasonic whistles were highly stereotyped and all but two had downsweep contours. These results demonstrate that specific sound categories can be shared by killer whales from different ocean basins. © 2012 Acoustical Society of America. Source

Noel M.,University of Victoria | Noel M.,Canadian Department of Fisheries and Oceans | Loseto L.L.,University of Winnipeg | Helbing C.C.,University of Victoria | And 3 more authors.
Environmental Science and Technology | Year: 2014

High trophic level arctic beluga whales (Delphinapterus leucas) are exposed to persistent organic pollutants (POP) originating primarily from southern latitudes. We collected samples from 43 male beluga harvested by Inuvialuit hunters (2008-2010) in the Beaufort Sea to evaluate the effects of POPs on the levels of 13 health-related gene transcripts using quantitative real-time polymerase chain reaction. Consistent with their role in detoxification, the aryl hydrocarbon receptor (Ahr) (r2 = 0.18, p = 0.045 for 2008 and 2009) and cytochrome P450 1A1 (Cyp1a1) (r2 = 0.20, p < 0.001 for 2008 and 2009; r2 = 0.43, p = 0.049 for 2010) transcripts were positively correlated with polychlorinated biphenyls (PCBs), the dominant POP in beluga. Principal Components Analysis distinguished between these two toxicology genes and 11 other genes primarily involved in growth, metabolism, and development. Factor 1 explained 56% of gene profiles, with these latter 11 gene transcripts displaying greater abundance in years coinciding with periods of low sea ice extent (2008 and 2010). δ13C results suggested a shift in feeding ecology and/or change in condition of these ice edge-associated beluga whales during these two years. While this provides insight into the legacy of PCBs in a remote environment, the possible impacts of a changing ice climate on the health of beluga underscores the need for long-term studies. © 2014 American Chemical Society. Source

Filatova O.A.,Moscow State University | Deecke V.B.,University of St. Andrews | Deecke V.B.,Vancouver Aquarium Marine Science Center | Ford J.K.B.,Canadian Department of Fisheries and Oceans | And 6 more authors.
Animal Behaviour | Year: 2012

Although killer whale, Orcinus orca, dialects have been studied in detail in several populations, little attempt has been made to compare dialect characteristics between populations. In this study we investigated geographical variation in monophonic and biphonic calls among four resident populations from the North Pacific Ocean: Northern and Southern residents from British Columbia and Washington State, southern Alaska residents, and eastern Kamchatka residents. We tested predictions generated by the hypothesis that call variation across populations is the result of an accumulation of random errors and innovation by vertical cultural transmission. Call frequency contours were extracted and compared using a dynamic time-warping algorithm. We found that the diversity of monophonic calls was substantially higher than that of biphonic calls for all populations. Repertoire diversity appeared to be related to population size: in larger populations, monophonic calls were more diverse and biphonic calls less diverse. We suggest that the evolution of both monophonic and biphonic calls is caused by an interaction between stochastic processes and directional selection, but the relative effect of directional selection is greater for biphonic calls. Our analysis revealed no direct correlation between call repertoire similarity and geographical distance. Call diversity within predefined call categories, types and subtypes, showed a high degree of correspondence between populations. Our results indicate that dialect evolution is a complex process influenced by an interaction among directional selection, horizontal transmission and founder effects. We suggest several scenarios for how this might have arisen and the implications of these scenarios for call evolution and population history. © 2011 The Association for the Study of Animal Behaviour. Source

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