Seismic survey and western gray whales

A gray whale Eschrichtius robustus 'spyhops' on the near-shore feeding ground off north-eastern Sakhalin Island, Russia. Photo: Yuri Yakovlev

Seismic survey and western gray whales

 

Commercial whaling had nearly extirpated gray whales Eschrichtius robustus in the western North Pacific by the 1960s. In fact, the 'probable extinction' of the so-called Korean stock was declared in a paper published in Journal of Mammalogy in 1974, soon followed by a note in the same journal referring to a handful of observations of gray whales in Korea and Russia in the late 1960s and early 1970s. A small and slowly increasing population of 'western' gray whales, red-listed as Critically Endangered, has since been closely studied since the late 1990s off north-eastern Sakhalin Island in the Sea of Okhotsk. The whales, including calves of the year, congregate in shallow near-shore waters to feed intensively during the brief open-water season. Among the greatest concerns for these whales' future, besides the ever-present risk of bycatch in fishing gear throughout their migratory range, is the expanding industrial footprint of oil and gas development on the Sakhalin Shelf. Seismic surveys, as sources of very loud impulsive noise, are a particularly contentious aspect of regional conflict between conservation and development. This Theme Section of ESR provides a series of detailed empirical analyses which, taken together, provide insights on how gray whales in a key feeding area respond to noise from a nearby seismic survey and, most importantly, how measures can be taken by operators to minimize the risks to the whales, monitor the impacts, and still acquire the needed geophysical data.

 

Articles belonging to this Theme Section were published upon completion in the respective issue of ESR. They are listed below as well as on the contents page of the respective issue of publication.

 

Editors: Randall Reeves, Okapi Wildlife Associates/IUCN SSC Cetacean Specialist Group (Guest Editor; rrreeves@okapis.ca); Greg Donovan, International Whaling Commission (Guest Editor; greg.donovan@iwc.int)

 

 

Bröker K, Gailey G, Muir J, Racca R

Monitoring and impact mitigation during a 4D seismic survey near a population of gray whales off Sakhalin Island, Russia

ESR 28:187-208 | Full text in pdf format | Corrigendum

 

 

Racca R, Austin M, Rutenko A, Bröker K

Monitoring the gray whale sound exposure mitigation zone and estimating acoustic transmission during a 4-D seismic survey, Sakhalin Island, Russia

ESR 29:131-146 | Full text in pdf format

 

 

Muir JE, Joy R, Bychkov Y, Bröker K, Gailey G, Vladmirov V, Starodymov S, Yakovlev Y

Delineation of a coastal gray whale feeding area using opportunistic and systematic survey effort

ESR 29:147-160 | Full text in pdf format

 

 

Muir JE, Ainsworth L, Joy R, Racca R, Bychkov Y, Gailey G, Vladimirov V, Starodymov S, Bröker K

Distance from shore as an indicator of disturbance of gray whales during a seismic survey off Sakhalin Island, Russia

ESR 29:161-178 | Full text in pdf format

 

 

Muir JE, Ainsworth L, Racca R, Bychkov Y, Gailey G, Vladimirov V, Starodymov S, Bröker K

Gray whale densities during a seismic survey off Sakhalin Island, Russia

ESR 29:211-227 | Full text in pdf format

 

 

Gailey G, Sychenko O, McDonald T, Racca R, Rutenko A, Bröker K

Behavioural responses of western gray whales to a 4-D seismic survey off northeastern Sakhalin Island, Russia

ESR 30:53-71 | Full text in pdf format