Refuge Notebook
Article
Dated
April 26, 2002
Elusive harlequin ducks can be spotted on peninsula's streams
by
Todd Eskelin
Last month marked 13 years since the Exxon Valdez ran aground
and spilled large quantities of oil in Prince William Sound.
For years,
scientists have been studying the impacts of the oil spill on the various marine
species in the Gulf of Alaska. I was curious which bird species had recovered
so I surfed the Web and found the Exxon Valdez Oil Spill Trustee Council Web page.
One species that jumped out at me was the harlequin duck.
I have been fascinated
by harlequin ducks since I was a kid out halibut fishing and saw these strange
colored ducks hanging out on the rocks. Back then I called them the clown ducks.
I was saddened to learn that they are one of the species in Prince William Sound
that continues to show signs of contamination.
If you have not seen a male
harlequin duck you are really missing out. The name harlequin was actually derived
from characters in Italian comedies that wore outrageous outfits and preformed
tricks. They have also been called sea mice, due to the funny squeaking noises
they make while feeding in groups. It is worth traveling to Homer or Seward to
take a day cruise just to see these birds.
They are often found feeding
in the intertidal rocky areas diving for crabs, clams, snails, and occasionally
small fish. That is probably why they were impacted by the oil spill. When the
oil hit the beaches and rocky outcroppings, it covered their preferred feeding
areas during fall, winter, and spring. Over the years, some of the oil has broken
down and disappeared, but some of the oil was buried in the rocks and gravel on
the beaches. This oil is then filtered and absorbed by the crabs and clams, and
eventually eaten by harlequin ducks.
So why am I writing about a sea duck
when I work at the Kenai National Wildlife Refuge (NWR)? It sounds like I should
be working for Alaska Maritime NWR in Homer.
Well, during summer, many species
of sea ducks travel inland to breed. Long-tailed ducks travel hundreds of miles
inland and can be found in Denali National Park. Spectacled Eiders go inland to
breed on the North Slope and can be found in the Arctic National Wildlife Refuge.
Harlequin ducks also travel inland and have been found breeding here on the Kenai
NWR.
Sometime around the end of April, male and female harlequin ducks will
move inland and the female will pick out a nest site. Typically, they nest on
the upper stretches of very clear, fast, high-mountain streams.
They feed
primarily on aquatic insects, but will also supplement their diet with salmon
eggs in the fall. After the female walks around and finds a nest site, the male
supervises while she collects nesting material and builds the nest. Then after
a brief courtship and mating, the male returns to the ocean until he is needed
the next summer.
The females are highly sensitive to disturbance while on
the nest, so they often build it on small islands in the middle of these tiny
streams. When disturbed, they often flush from the nest long before people or
predators are even in sight. This is one reason they often go unnoticed and why
I thought I would write this article.
It is likely that some of the harlequin
ducks that breed on the refuge spend their winters in Prince William Sound. The
number of harlequin ducks wintering in the Sound is double the estimated number
that breed in the area.
With all the changes going on in the refuge, i.e.
spruce bark beetles, wild fires, and development along the major rivers, we should
try and identify which streams currently support a breeding population of harlequin
ducks.
Due to the various threats to their populations, the East Coast population
was listed as endangered in Canada and threatened in Maine in 1991. The wintering
population on the East Coast is less than 1,500, down from historic estimates
of 10,000 birds.
We could possibly see the same thing happen here on the
West Coast if we don't pay attention. The population outside of Prince William
Sound has been fairly stable for the past 10 years, but who knows what the future
holds.
So, if you are out hiking on the dozens of small streams on the Kenai
Peninsula and you happen to spot a harlequin duck, write down the date and exact
location and give me a call at the Refuge 262-7021. I will be out checking many
of the likely spots myself, but I can only cover a small area and would appreciate
any sightings of this elusive duck.
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 columns
can be viewed on the web at http://kenai.fws.gov.
|