Project Methods and Results
Our project originally proposed to put 20 satellite tags on ringed seals during two years of field work (2007 and 2008). Conditions were good in 2007 for catching seals and 14 seals were tagged, more than half our goal. In order to have a good sample again in 2008, additional funds to purchase more tags were pursued. One of the things the tags will do is provide information about whether and how the tagged seals use the areas where Shell and other companies are exploring for oil and gas in the Chukchi Sea. For this reason, we wrote a proposal to Shell for funds to purchase additional tags. Shell supplemented our TWG grant with enough funds to purchase, deploy and download data for 13 more SPLASH tags.
The goal for the 2008 field season was to tag 15-20 ringed seals, preferably seals older than pups or yearlings. This is because many young seals (especially pups) do not survive through the winter. The Principal Investigators were Kathy Frost, Alex Whiting , and John Goodwin . The Research Assistants were Jeff Barger, Jerry Jones Sr., Doc Harris III, Cyrus Harris, Grover Harris Sr., Grover Harris Sr., Edward Ahyakak and Pearl Goodwin. Seals were tagged under Alaska Department of Fish and Game Scientific Permit No. 358-1787-01.
As in 2007, the base of field operations was located at the Tribal Elders Camp at the tip of the Sisualik spit 10 miles north of Kotzebue across the inner Sound. John and Pearl Goodwin were the field managers of the camp and directed catching and tagging activity. There were two seal catching crews in 2008, one led by John Goodwin and the other by Cyrus Harris.
The field camp was established on October 2nd. Biologist Kathy Frost arrived at camp on October 9 th and left on October 22nd. ADF&G biologist Justin Crawford, who will be mapping the ringed seal tagging data during the winter, flew to Kotzebue and spent several days at seal camp near the end of the project learning about the tagging operation and photographing the tagging crew doing its work.
Jim Kincaid of Northwestern Aviation supplied transportation to and from Kotzebue for personnel and supplies. All-terrain vehicles were used to transport supplies, gear, seals, personnel, boats and generally be able to move about Sisualik. Boats small enough to be beached were used to check nets.
Seals were caught with the same nets that were used in the Kotzebue Sound bearded seal tagging project and for the 2007 ringed seal project. After the 2007 field season, the nets were repaired and re-hung. They got new float rope to replace the old worn out float rope and all of the nets were re-dyed because they had faded over the previous four years. Zippers were removed and sections were sewn together to make four 250-long straight hanging nets.
Capture activities began on October 2nd, 2008 , the first night the camp was established. Each of the two crews had its own boat and set out and tended two 250-ft seal nets, for 1000 ft of net in the water each day. The nets were set at different locations along Sisualik spit depending on water and ice conditions and where the seals seemed to be. The nets were in the water fishing every night except one (due to ice) for the next three weeks. Kotzebue hunters conducted all seal capture activities.
When a seal was caught, it was removed from the net and placed in a hoop net in the boat for transfer back to the beach. Seals were taken out of the boat and moved from the boat to camp using an ATV with a trailer to hold the seal.
When a seal reached camp, it was either sampled and released if it was too small or tagged if it was big enough. The seals that were released without satellite tags were weighed and measured. Sex was recorded, a small skin sample was taken from the hind flipper for genetic testing, blood was taken, and a numbered plastic tag was put in the hind flipper. Measurements included curve length from the tip of the nose to the tip of the tail, straight length from the tip of the nose to the tip of the tail, girth behind the front flippers, and maximum girth around the belly.
If a seal was large enough (more than 60 pounds), it was also satellite tagged in addition to everything that was done to smaller seals. The taggers put a small amount of acetone on the fur to clean it and rubbed the fur dry. The tags were fitted in the neck saddle as it slopes towards the shoulders. The correct spot for the tag was drawn with a black marker. The 5-minute epoxy glue was mixed in two small batches. The first batch went onto the bottom of the tag and also on the mesh and fur of the seal. The glue was spread in a very thin layer so that it didn't get too hot on the seal's skin. When that layer dried, the second batch was used to cover any places that were missed. After the second layer of glue was dry, the tag was turned on, data sheets were checked to make sure the tag number was written down and all of the data were complete, and the seal was taken to the water and released.
For the first time in 2008, we were able to spin blood and separate the serum in camp instead of bringing it back to town. ADF&G purchased a battery operated centrifuge for the project to use. After seal handling and tagging operations were completed for the day, blood was taken inside, spun for 20 minutes in the centrifuge, and the serum poured off into special vials for freezing.
The first 2008 ringed seal was caught on October 3rd, the first night the nets were set, but it was too small to tag. The first tagger seal was caught on October 10th. Twelve more ringed seals were tagged between then and October 21st, for a total of 13. In addition, 29 other small ringed seals were caught, sampled and released. DNA samples were collected from all 42 seals, and blood was taken from 31.