GREATER SCAUP PAIR – A male greater scaup follows his mate across their nesting pond early in the breeding season. The male has a dark, rounded head that shows an iridescent green sheen in good light. Lesser scaup, that occur here only infrequently, have a slight peak at the back of the head and the male’s head has a purplish iridescence. These features can only be seen up close and the birds are indistinguishable at a distance.CRECHE OF DUCKLINGS – A female greater scaup leads a crèche of 21 ducklings along the shore of Swan Lake. Occasionally a female will depart soon after her eggs hatch, leaving her brood in the care of another female with young. A crèche is a group of young from more than one brood, tended by one or more females. Crèching is not unusual for mergansers and common eiders but occurs far less often with scaup. This was the only scaup crèche I have seen.

Greater Scaup––The life of a common duck nesting on the Seward Peninsula

The greater scaup is a handsome, solidly-built diving duck that breeds across the circumpolar north. They are a familiar sight in this region, since greater scaup are one of the more common and widespread ducks nesting along freshwater lakes and ponds of the Seward Peninsula.

The male, with his starkly contrasting white, gray and dark markings, would be unmistakable if not for his close relative, the slightly smaller but hard to distinguish lesser scaup. However, lesser scaup breed in Alaska’s interior and more southerly regions and are only infrequently seen here.

Greater scaup return to breed on the peninsula in mid-May to early June. The birds usually arrive in pairs, having already bonded for the season, often returning to the female’s previous breeding area. In late springs such as this one, they may find their ponds still frozen, which delays nesting.

Scaup nest along waterbodies that vary in size from tiny ponds to large lakes. Certain features are important: wetland shorelines where grasses and sedges grow; open water for diving; and vegetated shallows where ducklings can feed.

The hen picks a nest site, usually near the shoreline, and hides her nest in a clump of dried grass left over from the previous year. She makes a depression on the ground which she lines with fine grasses and increasing amounts of down plucked from her own breast as incubation progresses.

She lays an average of eight or nine eggs, one per day, and incubation begins when the last egg is laid. Her mate typically stays at the nest site for about half of the 25-day incubation period, which allows the pair to renest if the clutch is lost early in incubation. The male then leaves the breeding ground to join other males at a traditional, secluded molting area while he is flightless.

Newly hatched ducklings are covered in brown down, and ready to go as soon as their down dries. Within 24 hours the chicks follow their mother into the water. She keeps her brood together and leads them to the shallows to feed.

At first the ducklings feed themselves on insects and larvae at the surface, but soon they can dive along the shoreline for submerged aquatic invertebrates.

Eggs and ducklings are vulnerable to predation by gulls, jaegers, ravens, foxes and mink. Northern pike can snatch ducklings from below.

Females attempt to deflect predators with distraction displays and by feigning injury. Their alarm calls cause ducklings to scatter, dive underwater and disappear into submerged vegetation, where they are hidden from view.

The hen stays with her brood until they are nearly grown but leaves them before they can fly. Then, it is her turn to molt. She flies to an isolated lake with abundant food and good cover and stays there while flightless.

Greater scaup dive to find food in the water and on the bottom, occasionally feeding at depths of up to 23 feet.

Adults eat roughly equal proportions of animal and vegetable matter. On the breeding grounds their diet consists of aquatic plants, seeds, tubers, aquatic insects and larvae, crustaceans and mollusks.

After the molt, the males move to coastal river deltas, estuaries and lagoons to stage for fall migration. These pre-migratory gatherings begin forming during the second week of August. Scaup numbers build up through late August and the first half of September as females and recently fledged juveniles arrive.

In the Nome area, Safety Sound is an important staging area for scaup during fall migration. Large flocks can be seen there, diving to feed on aquatic plants and invertebrates, and roosting on the rich waters.

In mid-September numbers drop sharply as the ducks depart. A few scaup, mostly juveniles from late broods, may remain until freeze-up.

In North America, the majority of greater scaup winter in marine waters along the Atlantic coast, including many scaup from Alaska. A smaller number winter along the Pacific coast as far north as the Aleutian chain.

Seward Peninsula’s scaup are thought to winter along both coasts, with the majority traveling across North America to the east coast.

Greater scaup are still common throughout their range, but their numbers are declining rapidly. They are listed as a “common species in steep decline,” which means their population is estimated to be 50 percent of what it was 40 years ago.

Eighty percent of the population winters along the Atlantic Coast, often in urban areas where they contend with contaminants, habitat degradation and disturbance. High levels of heavy metals and other contaminants have been measured in scaup tissues and eggs. These factors, along with climate change and hunting, are perhaps contributing to the decline.

In 2023, the annual U.S. Fish and Wildlife waterfowl survey on the northern Seward Peninsula found greater scaup numbers roughly unchanged from the most recent 10-year average.

Many scaup and other waterfowl got off to a late start this spring, but as July progresses keep an eye out for broods of downy, brown scaup ducklings diving energetically on local ponds.



The Nome Nugget

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Nome, Alaska 99762

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