Refuge Notebook
Article
April
16,2004
Possible title: Gulls Migrate Great Distances for Summer on the
Kenai
By Todd Eskelin
Spring has finally sprung and the first migrant
birds have returned to the Kenai Peninsula. Many people would assume the first
migrant species is a robin or maybe a Canada Goose. Actually, the goose
is a very good guess and would net you the number two spot in the migration game.
Number one on our list is the gull. Most people would say that gulls
are not migratory, they are just dump birds. Well, after reading about some
of the fascinating results from some early studies of gulls on the Kenai National
Wildlife Refuge, you may have a different opinion of gulls.
In the early
1980's refuge staff and folks from the Migratory Bird office in Anchorage set
out to learn about the colony of Glaucous-winged Gulls nesting on Skilak Lake.
They found a similar colony on Lake Louise north of Anchorage and did similar
studies up there, as well. I am only going to tell you about what they
found with the Kenai population, but the Lake Louise population basically mirrored
what was found down here.
The method these scientists chose to study the
gulls was to band the chicks with a standard aluminum band on the right leg and
a bright yellow plastic band on the left leg. The plastic bands had unique
alphanumeric codes that could be read from a great distance with binoculars.
So, toward the end of July and early August 1983 they banded a large number of
gull chicks. They repeated this exercise again in 1984.
As
the birds dispersed, reports began coming in from various locations where the
color-banded birds were spotted. The researchers were shocked to discover
that these birds actually migrated great distances each year and then returned
to Alaska in the spring.
There were too many re-sightings to list
individually, so I will just summarize the results. Basically, the young
gulls would move up anddown the >Kenai >River > as soon as they could
fly. They concentrated at the >Russian >River >, the outlet of
the >Kenai >River > where it empties into Skilak > Lake> and down
at the mouth of the river near the >Port of >Kenai>. They hung
arounduntil the end of August and early September then started their journey south.
Over the next 2 months, sightings were scattered from Kodiak to Prince William
Sound.
By December the birds were moving through >Southeast Alaska
> and British Columbia with a few arriving in California >. The ultimate
wintering grounds were split into several areas along the >Pacific >Coast
>, with concentrations on the >Columbia River near Portland > and another
centered around >San Francisco > Bay > on the >California > coast.
Birds weresighted at these areas through February.
Surprisingly, there are
no spring sightings of the banded birds on their northbound journey. No
sightings were recorded until May, when they begin showing up around the >Kenai
Peninsula. It may just be a coincidence, but the birds might have routed
over the Gulf of Alaska, making them impossible to view.
Gulls are
slow to mature and they don't actually return to the breeding grounds until they
are around 5 years old. For the next few summers the banded birds spent
summers around coastal >Alaska > and usually didn't return to their birthplace
on the Kenai. Eventually, when they reached breeding age, many returned
to the rocks on Skilak > Lake >.
The book record for the oldest banded
Glaucous-winged Gull is 24 years 9 months. So, it is possible that some
of the banded gulls are still around. While counting the gulls at the Skilak
> Lake > colony a few years ago, I was able to spot several banded gulls.
The plastic leg bands had all worn off, but the aluminum bands were still present.
So,
as the migrant birds begin to filter in, take notice of the Glaucous-winged Gulls.
These hardy birds have traveled a great distance to enjoy the beautiful weather
and bountiful food that the >Kenai Peninsula provides.
Also, remember
to call the Central Peninsula Bird Hotline (262-2300) and report the first arrival
date of any migrant birds in our area. The Kenai National Wildlife Refuge
is sponsoring a contest for the person who documents the first arrival date for
the most species between now and June 15th.
Todd Eskelin is a Biological
Technician at the Kenai National Wildlife Refuge. He specializes in birds
and has conducted research on songbirds in many areas of the state. Previous
Refuge Notebook articles can be viewed on the Refuge website at http://kenai.fws.gov/.
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