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Report on 2002 field season
 Exceptionally
early melt of snow and breakup of sea ice.
 Early
snow and ice melt made the start of the 2002 Cooper Island
field season unlike any in the previous 28 years. A warm
April and May resulted in the earliest recorded snow disappearance
at Barrow. When they became aware of the rising temperatures
in northern Alaska, George Divoky and his 2002 field assistant,
Katie Pindell, rushed to Barrow to try to get out to the
island by snow machine before the nearshore ice was covered
by water from the melting snow.
Unfortunately, by 27 May water covered much of the 20 miles
of nearshore ice between Barrow and Cooper Island and there
were also indications that patches of ice might be too thin
for safe travel. Since airplanes capable of landing on Cooper
Island's gravel beach are no longer available in Barrow,
eight trips in a small helicopter were necessary to get George,
Katie and their supplies to the field camp. Upon arrival
the ice conditions around the island were unlike any George
had ever seen from the island in June.
 Typically, Cooper Island is surrounded by continuous pack
ice until sometime in July with little ice-free water present
within 10-20 miles. In 2002, there was a patch of open water
directly northeast of Cooper Island that extended all the
way to the horizon. Satellite imagery showed the ice-free
waters open water had been present since late May . For the
first year since 1975, when the study began, there was water
and not ice on the beach for the birds' arrival.
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Early
egg laying and increase in number of breeding birds
 The
Black Guillemots initially appeared to benefit from the warm
weather in spring and early summer. Snow had melted from
most nest entrances by the time the guillemots arrived the
first week in June. This allowed the median date of egg-laying
(the day on which half of the active nests in the colony
have eggs) to equal the earliest date on record. The close
proximity of ice-free waters also changed the schedule and
behavior of the guillemots during the early breeding season.
Guillemots are diving birds that need open water both to
have access to their prey but also to provide areas where
they can dive to avoid capture by avian predators such as
Peregrine Falcons and Snowy Owls. When the nearest open water
is ten to twenty miles away, birds must "commute" over
the nearshore ice to feeding areas and will also temporarily
abandon the colony when an avian predator visits the island.
In 2002 the patch of open water just northeast of Cooper
Island allowed birds to feed near the colony and also move
a much shorter distance in response to predation risks. The
early melt of snow and ice probably made the early breeding
season easier for first-time breeders and may have contributed
to one of the larger increases in the breeding population
in the last decade, with the colony going to 145 pairs from
125 pairs in 2001.
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Mid-August
storm pushes pack ice offshore and leaves Polar Bears on
the beach.
 A
cool late June and July kept the pack ice onshore from Barrow
and along the Plover Islands (of which Cooper Island is the
largest) but mid-August brought warm air and strong winds
from the Bering Sea. A storm with wind speeds near 50 mph
pushed the ice from the shoreline almost overnight on 15-16
August. The displacement of the pack ice decreased the availability
of ice-associated prey to guillemot parents feeding their
young and also stranded a large number of polar bears on
the Beaufort Sea coast east of Cooper Island.
Polar bear sightings have been rare on Cooper Island in
the past 28 years but from 15-18 August 2002 over 20 bears
walked west on Cooper Island heading north along the Plover
Islands. Most passed within a few hundred yards of our camp.
After 10 bears went by in a 24-hour period it became clear
that data gathering and sleep would not be possible and George,
Katie and volunteer Evan deBourguignon left the island. Not
having time to charter a boat or plane from Barrow we were
extremely grateful that the North Slope Borough's Department
of Search and Rescue came out to the island in their helicopter.
The assistance of the people of Barrow and especially the
North Slope Borough has always been critical in maintaining
the Cooper Island field camp but never was it more needed
or appreciated than during this past summer's polar bear
invasion.
We returned to the island by boat later in the week to pick
up our gear and found that bears had eaten over three-quarters
of the guillemot chicks on the island. It is unlikely that
the bears killed any adult guillemots since parent birds
do not spend any time in the nest cavity during the nestling
period once chicks are able to maintain their own body temperature
at approximately six-days of age.
After the field season was over the arctic pack ice remained
far offshore and the stranded polar bears gathered at Point
Barrow in numbers to feed on the remains of whale carcasses.(Read
article)
One bear wandered inland in search of food and was found
100 miles south of Prudhoe Bay.
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