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.
Peninsula Clarion ©2013. All Rights Reserved.