Contents:
Late winter 2002 survey info
Meet our newest caribou
What's new?
Locations of radio-collared Porcupine
and Central Arctic Caribou
courtesy of Steve Arthur, ADF&G
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In late February, Fran Mauer with the U.S. Fish and Wildlife Service started radio tracking flights to determine the distribution of collared Porcupine Caribou within their winter range, as well as the overlap between Porcupine Caribou and neighboring herds. A total of 169 radio-collared caribou were located. These included 62 from the Porcupine herd and 107 from the Central Arctic herd.
The Porcupine herd included two main groups: one occupied the area
surrounding the Ogilve River Basin in the north-central Yukon while the
other was centered in the southern foothills of the Brooks Range just east
of Arctic Village, Alaska. Most of the Central Arctic herd was found in the
Chandalar River drainage just south of the crest of the Brooks Range and
east of the Dalton Highway, although a significant number were also found on
the north side of the Brooks Range. With two exceptions, the two herds
seemed to be occupying separate winter ranges, although one Porcupine
caribou cow was found near a group of Central Arctic caribou, and one
Central Arctic cow was found near Arctic Village with a group of Porcupine
caribou. Similar cases of overlap between these herds have been observed in
the past, but most caribou cows return to their herd's traditional calving
areas during the spring migration.
On March 5, Steve Arthur with the Alaska Department of Fish and Game captured 10 cow caribou for deployment of radio collars. He also captured Isabella, and fitted her with a new satellite collar. Isabella's collar was getting old, and due to go off the air in late summer 2002. With her new collar, we will be able to track Isabella's movements for the next 3 years.
Capture and composition count locations
for Porcupine and Hart River Caribou
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Between March 9 and 12th, Yukon Wildlife Management technicians, accompanied by Dawson First Nation fish and wildlife steward Steven Kormendy captured and classified Porcupine Caribou on the Yukon side of the range. At the southern extent of their winter range, Porcupine Caribou were mixed with caribou of the Hart River Herd, which are woodland caribou. We have long known that Porcupine Caribou and Hart River caribou share winter range. However, the area of overlap is typically east of the Dempster Highway when Porcupine Caribou move into the Hart basin, which is the usual area of concentration of Hart River caribou during winter months. This year, radio-collared Hart River caribou were north and west of the Dempster in the upper Ogilvie Basin, well outside their known winter range. In areas outside of the overlap between these herds, 12 caribou were fitted with new radio collars, and one cow caribou was chosen at random to wear a new satellite collar.
In a seperate project towards the end of March, 17 Hart River cow caribou were captured and fitted with radio-collars, so that we can continue to monitor the overlap between the two herds during winter months.
Meet our newest caribou
Catherine on the day of capture!
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"Catherine" was captured on March 12th, south of the Ogilvie River. We had been hoping to recapture and recollar either Lucky or Blixen, but as the radio transmitter portion of their collars are not working, we were not able to locate them amongst the 1000's of caribou in the area. Catherine was chosen as she is a young animal and in very good condition. She was named by the 2001 Johnny Charlie Scholarship recipient and assistant wildlife technician, Kieran O'Donovan. Kieran worked with Dawson Regional Biologist Dorothy Cooley during the summer of 2001.
Composition counts were conducted in both Yukon and Alaska. 7,093 Porcupine caribou were classified. We found 31 calves per 100 cows, and 29 bulls per 100 cows. The calf to cow ratio is reassuring after the low calf survival last year. We hope to see between 30 and 35 calves per 100 cow during March counts. Bull ratios are often biased, as we don't always find enough bull groups to be representative of the March ratio.
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