First record of common bottlenose dolphin (Tursiops truncatus) in Canadian Pacific waters

Abstract

Background: Common bottlenose dolphins (Tursiops truncatus) are distributed globally in tropical and warmtemperate waters with coastal and offshore ecotypes known. In the eastern North Pacific Ocean, common bottlenose dolphins are typically found in offshore waters as far as 41°N and in coastal waters as far as 38°N. Despite considerable survey effort, the species has not been previously recorded in Canadian Pacific waters. Results: On 29 July 2017, a group of approximately 200 common bottlenose dolphins were observed together with approximately 70 false killer whales (Pseudorca crassidens) in waters of 16.5°C at 50°N during a pelagic seabird and marine mammal survey off the west coast of northern Vancouver Island, British Columbia, Canada. Conclusions: This sighting represents the only occurrence of common bottlenose dolphins recorded in Canadian Pacific waters and, to our knowledge, is the most northerly record for this species in the eastern North Pacific. It is also the first sighting record of false killer whales in non-coastal waters in British Columbia, Canada. The occurrence of both species may be associated with a prolonged period of warming in offshore regions of the eastern North Pacific.

Acoustic and visual cetacean surveys reveal year-round spatial and temporal distributions for multiple species in northern British Columbia, Canada

“…We could not confidently differentiate between dolphin species based solely on these recordings, delphinid whistles at GS and RI could have been mostly produced by Risso’s dolphin, but further analysis is required. Other whistle-producing delphinids are only very rarely encountered in BC and include: common dolphins ( Delphinus delphis and Delphinus capensis ), false killer whales ( Pseudorca crassidens ), short-finned pilot whales ( Globicephala macrorhynchus ), striped dolphin ( Stenella coeruleoalba ), and bottlenose dolphins ( Tursiops truncatus ) 13 , 32 . These species are not likely to have contributed much to the overall delphinid occurrence, but cannot be ruled out without further analysis.…”

A bowhead whale in the eastern North Pacific

“…The occurrence of a juvenile bowhead whale in Caamaño Sound, British Columbia represents the first confirmed record of this species in the eastern North Pacific despite intensive whaling efforts that took place in this region throughout the 19th and early 20th centuries (Clapham et al, 1997 ; Gregr et al, 2000 ; Reeves et al, 1985 ; Townsend, 1935 ) and significant cetacean research effort from Alaska to California in more recent decades (Barlow, 2016 ; Ford et al, 2010 ; Nichol et al, 2017 ; Rone et al, 2017 ; Wright et al, 2021 ). This sighting also represents the first natural occurrence in Pacific Canadian waters of any of the three cetacean species that are year‐round residents to the Arctic [bowhead whale, narwhal ( Monodon monoceros ), beluga ( Delphinapterus leucas )], as most extralimital cetacean occurrences in western Canada are of tropical species associated with warm water events (Halpin et al, 2018 ).…”

Northern Range Expansion of California Coastal Bottlenose Dolphins (Tursiops truncatus)

“…At the height of this marine heatwave, numerous invertebrate and vertebrate marine species set new northern range records on the West Coast (Sanford et al, 2019). These records included a large group of likely offshore ecotype bottlenose dolphins sighted in 2017 at 50º N off British Columbia (Halpin et al, 2018), approximately 1,000 km north of this stock's typical range, suggesting at least a temporary shift in response to ocean warming in the eastern North Pacific.…”