Harlequins specialize in turbulent water

Posted: Sunday, May 18, 2003

One of the most interesting sea ducks to watch in winter and early spring in Southeast is the harlequin duck. Harlequins are rough-water specialists. They seem to relish bouncing around in turbulent seas or perching on rocky points and reefs while the water crashes over their feet.

You'll recognize the males because of their colorful markings. Like no other duck in Southeast Alaska, they have white spots and stripes on slate-blue bodies, and chestnut-colored flanks - a wildly variegated costume like those worn by medieval court jesters, or the stock character of Italian comedies after which harlequins are named.

Barry Bracken, a marine biologist and naturalist who conducts marine ecotours through Kaleidoscope Cruises in Petersburg, says harlequins are his favorite sea ducks.

"They're the one species we have in front of our house year-round," he said, "and they're great fun to watch. You can watch them foraging in rough, rocky surge areas that other birds can't tolerate, and they also spend a lot of time on the rocks resting, while other ducks, like surf scoters and mergansers, are out bobbing on the waves."

In salt water harlequins feed on a wide variety of invertebrates, diving down to pluck them from rocks and the bottom close to shore. They eat mollusks such as snails, mussels and small clams; crustaceans such as hermit crabs and shrimps; and amphipods, small, laterally flattened invertebrates such as beach hoppers and skeleton shrimp. They are one of the few ducks that can feed on limpets and chitins - they pry them off rocks using a sharp hook on their beaks.

Harlequins are the only sea ducks that commonly nest in Southeast. In late winter you might hear male harlequins courting females, making what Bob Armstrong, author of "Alaska's Birds," calls "a mouse-like squeaking or a low whistle ending in a long trill."

In April or May mated pairs head up to fast-moving streams on the mainland to nest. The females stay up there for a long time - nearly a month - to incubate their eggs and for another month or so to rear their young. Males return to salt water shortly after the eggs hatch, around late June, probably to avoid competing with females and chicks for a limited food supply.

While they're living along freshwater streams the harlequins' ability to contend with rough water and strong currents serves them well. They spend a lot of time foraging underwater, eating mostly larvae of aquatic insects. Armstrong said he watched a nesting harlequin in a stream near the Mendenhall Glacier one summer.

"I could see it swimming underwater," he said. "It would push up rocks with its bill and gobble like crazy. It was obviously taking invertebrates dislodged by the current."

Bracken said young harlequins often exercise by playing in waterfalls, sometimes suffering a higher mortality from this "whitewater rafting" than from predators. Armstrong said he saw that once.

"I was watching fish at Sheep Creek falls," he said. "Suddenly an entire family of Harlequins - a female with young - came shooting over the waterfall. They hit the water at the bottom and just bounced off. It was amazing."

Bracken said harlequins are a good reminder of the important links between marine and freshwater environments.

"They need a pristine marine environment as well as a pristine terrestrial one for breeding. They're a good reminder for us that little changes in one area can have a profound influence over a much broader area - that we need to take care of everything and keep everything in balance."

Southeast Wild is provided by the Juneau Audubon Society. Spring migration bird walks continue through June 7. For the schedule, see the society Web site at www.juneau-audubon-society.org. Monthly meetings resume in September.

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