Marine scientists focused on the Arctic Ocean, Bering Sea and Gulf of Alaska presented a plethora of research results to several hundred participants at the 2024 Alaska Marine Science Symposium in Anchorage Jan. 29-Feb. 2, while acknowledging the unknowns that are still to be determined.
Associate Professor Peter Westley of the University of Alaska Fairbanks’ College of Fisheries and Ocean Sciences offered an update on his research into chum salmon on tributaries of the Colville River in Arctic Alaska, where fish are caught for subsistence from Kaktovik to Point Hope.
Ongoing studies, which Westley said he hopes will yield more information by the fall of 2024, are to determine the diet of these chum, their size and abundance.
All five species of Pacific salmon have been encountered on Alaska’s North Slope, but the unanswered question is whether they are establishing territory in that area, rather than simply straying there.
Westley said muscle tissue taken from some of the 55 spawned out individuals and recovered carcasses will prove invaluable for investigating questions of fish provenance and establishment, including what they are eating and how their diet may vary from that of chum salmon found in other areas of Alaska.
Stable isotopes are to be employed for that research.
Westley’s presentation focused on highlights of his most recent fieldwork in the fall of 2023 that provided unequivocal evidence of spawning chum salmon in the Anaktuvuk and Itkillik rivers, tributaries of the Colville River.
The complex anadromous salmon life history requires substantially more work to assess the ultimate fates of Pacific salmon spawning in Arctic waters, he said.
Wesley’s UAF faculty colleague Russell Hopcroft gave a keynote presentation on his research into zooplankton of the Gulf of Alaska, noting that while surface waters of the Gulf have been studied for decades, that communities in deeper water are virtually undescribed, except for a few keystone species.
He said that scientists use all kind of tools to image zooplankton, each with their own inherent biases, weaknesses and strengths.
“No single net can assess the whole zooplankton community,” he said.
Hopcroft said his research team used tools ranging from plankton nets to Remotely Operated Vehicles (ROVs), with analyses that encompass classical morphology, video recordings and molecular identification.
In particular, he said, they emphasize the exquisite beautify of the deep-water macro fauna, such as jellyfish ctenophores, and squid, that are prominent and charismatic components of the midwater communities.
Diversity tends to increase with depths of the ocean, he added.
Serena Alstrom Fitka, executive director of the Yukon River Drainage Fisheries Association, addressed the importance of incorporating traditional knowledge into western science.
Fitka expressed great concern over the demise of salmon in the Yukon River, which she said is forcing area residents to incorporate other fish into their diets and to hunt for moose and other wildlife.
The complete book of abstracts for the 2024 symposium is online at https://online.flippingbook.com/view/832931631/.