A rare find: Marine mammal tracker found in Golovin
A Golovin resident recently happened upon a rare find on a beach near Golovin: a seal satellite tracker, which came off a bearded seal that was tagged in September 2017 in Koyuk.
The tags are glued on to the seal’s coat and, in theory, come off when the seals molt in spring. Usually these expensive trackers sink to the ocean floor to never be seen again. This one somehow ended up ashore.
According to Justin Crawford with the Arctic Marine Mammals Program of the Alaska Department of Fish and Game, this particular tag came off a young male bearded seal that was tagged on September 21, 2017. “The seal was captured and tagged on the Koyuk River by Merlin Henry, his grandson Jeremiah Henry, and two members of the Alaska Department of Fish and Game’s Arctic Marine Mammal Program, myself and Ryan Adam,” explained Crawford.
A few weeks ago, Gay Sheffield, UAF Alaska Sea Grant agent for the Bering Strait region, received the report from the Golovin resident, who wishes to remain unidentified, that she found a marine mammal tracker on the beach. The reason that she could identify the rectangular box with an antenna as such was that she has seen one of those before at a different research project in 2001. Sheffield asked the Golovin resident to ship the tracker to Nome to identify whom it belonged to. “Knowing that there are multiple research projects throughout the Arctic that put tags on seals, this tag could have originated from anywhere in the Arctic,” Sheffield said. There are several different seal tagging programs, including a program by Alaska Department of Fish and Game, a separate tagging program by the North Slope Borough Wildlife Management and yet another one by NOAA’s Polar Ecosystem program.
On the tracker was the name of the manufacturer, an email and the serial number. After talking to the manufacturer in Scotland, Sheffield was able to identify that ADF&G deployed the tracker.
As the Ice Seal Committee is co-management partner, Sheffield handed the tracker to Ice Seal Committee representative for the Bering Strait region, Brandon Ahmasuk.
Crawford explained the seal tagging project under ADF&G’s auspices.
The tag that was found near Golovin is a so-called CTD tag, short for Conductivity-Temperature-Depth, and the thing costs $4,950. “In addition to location, dive, and haul-out behaviors, this tag collects oceanographic measurements,” Crawford wrote in an email.
“Our program conducts two separate studies involving the tagging of seal,” Crawford explained. “One [is] funded by the Bureau of Ocean Energy Management (BOEM) titled “Ice Seal Movements and Foraging: Village-based Satellite Tracking and Collection of Traditional Ecological Knowledge Regarding Ringed and Bearded Seals” and the other funded by the Office of Naval Research (ONR) titled “Movements and Habitat Use of Pacific Arctic Seals and Whales via Satellite Telemetry and Ocean Sensing”. The overall objective of these studies is to work with subsistence hunters to deploy satellite transmitters on Arctic seals, and whales under the ONR study. In addition to studying seal movements, habitat use, and behavior, the BOEM study incorporates Traditional Ecological Knowledge, gathered from interviewing hunters, into our understanding of seal biology and the ONR study incorporates oceanographic measurements into our understanding of important foraging areas for seals and whales.”
According to Crawford, they have trained taggers in three Norton Sound communities: Merlin Henry in Koyuk, Alexander Niksik in St. Michael and Tom Gray in Nome. “These three tagging crews have captured and tagged 24 seals since 2014,” he noted.
The goal of the project is to document year-round movements and habitat use of seals “relative to oceanographic conditions and other factors such as ice cover and human-related disturbance.” The movements of individual seals can thus be tracked year-round and provide information on distribution, movement, migration and diving behavior. This information is useful to identify important feeding, summering and wintering areas and the oceanographic conditions in those areas, Crawford explained.
Brandon Ahmasuk said the information this tracker holds is invaluable. “The chance of finding those things is minimal,” he said.
Crawford concurred, saying that it is rare that tags are found. “Since we started tagging seals in 2007 we’ve deployed 116 tags and only five have been returned, either from being found or the seal was harvested and the hunter contacted us. Only five tags in 10 years,” he noted.
A map with the seal’s movements reveals the animal’s movements from September to November.
Crawford described that the seal left the Koyuk area soon after being tagged. It moved along the northern shore of Norton Sound and looped back and forth between Golovin Bay and Sledge Island before moving into Golovin Bay in late October. “The last location we received from the tag was in Golovin Bay on November 9. We don’t know how the tag fell off the seal in November since the tag should have stayed on until the seal molted the following spring,” he wrote.
Crawford said his office sends project updates and maps of seal movements weekly to a list of interested people, including subsistence seal hunters, IRA and city offices from Bering, Chukchi and Beaufort sea communities, the Ice Seal Committee, industry, collaborating agencies, and universities.
If anyone would like to be added to the list of people receiving updates on this project they should contact Justin Crawford at firstname.lastname@example.org.
There are no laws against subsistence hunters harvesting tagged seals. Crawford said the department offers a reward for trackers that are returned because they are expensive and can be reused again on a different seal.