by Wyatt Fournier from the Northwest Explorer
The Second Leg of the 2011 Summer Survey in the Western Gulf of Alaska has begun! Once again, researchers and students from Alaska and Washington State are onboard the F/V Northwest Explorer conducting surface trawls with concurrent oceanography and acoustic profiling. Our science crew consists of lead acoustician Jennifer Nemura (University of Washington), lead oceanographer Ayla Doubbleday (University of Alaska, Fairbanks graduate student), Brendan Coffin, Michael Kohan (both University of Alaska, Juneau graduate students), seabird / marine mammal observer Jackelyn Slawson (US Fish and Wildlife), and Chief Scientist Wyatt Fournier from NOAA’s Alaska Fisheries Science Center, TSMRI, in Juneau, Alaska.
Our research goal is to identify and quantify major ecosystem processes that regulate recruitment strength of key groundfish species in the Gulf of Alaska that are commercially and ecologically important. We’re studying five key species in particular: arrowtooth flounder (Atheresthes stomias), Pacific cod (Gadus macrocephalus), Pacific ocean perch (Sebastes alutus), sablefish (Anoplopoma fimbria), and walleye pollock (Theragra chalcogramma).
Recruitment and survival of these species depends on a biophysical gauntlet that occurs as they switch from an early life history offshore pelagic phase to a nearshore settlement phase. To investigate the mechanisms affecting recruitment and survival, we will contrast two regions: the western Gulf of Alaska with a broad shelf dominated by high oceanographic variability and large demersal fish biomass, and the eastern Gulf of Alaska with a narrower shelf, lower demersal biomass, and higher species diversity.
|The first leg of our survey in July covered the eastern Gulf grid, and our survey this month will cover the western Gulf grid.