Birder’s Notebook: Steller’s Eider––The little eider

Unless you live on St. Lawrence Island, Steller’s eiders aren’t a bird you are likely to see very often in this region. So, in early November when I spotted two of these small, flatcrowned, brown eiders close to shore just below the Safety Bridge I settled in to watch them.

The hungry ducks were dabbling along the rocky shoreline, occasionally tipping tails up to feed below the surface. Their appearance and behavior reminded me more of puddle ducks than their deep-diving, ocean-going relatives––the common, king and spectacled eiders.

Steller’s eiders are the smallest and rarest of the four eider species. They differ from their eider relatives enough to be placed in a genus of their own––“Polysticta.”

Inspired by the outlandish plumage of the breeding male, the genus name means “many spotted” in ancient Greek. The genus of the other three eiders, “Somateria,” in ancient Greek translates to “wooly bodied.”

All eiders are sea ducks of the far north. Unlike their larger kin that typically winter in the deep waters of northern seas, Steller’s eiders usually winter in shallow, nearshore waters of coastal lagoons.

Although Steller’s eiders are able to dive deeply for prey, the dabbling behavior I observed at the Safety Bridge is more typical. They feed on marine invertebrates, seeds and insect larvae, straining prey through their stout, broad bills.

The smaller, lighter bodies of Steller’s eiders allow them to take off easily from the water without the running start across the surface required by the larger, deep-diving eiders.

A large part of the Steller’s eider population migrates north through the Bering Strait in the last half of May, mostly on the Russian side. A few migrants may pass through the Seward Peninsula’s coastal waters, the males in their spectacular breeding plumage, for those lucky enough to see them. Occasionally a few nonbreeders in plain brown plumage may be seen along the peninsula’s coastline over the summer.

The showy sea ducks are a more regular sight at St. Lawrence Island, but since the early 1990s, spring and fall passage has greatly declined. Steller’s eiders were once a rare and irregular breeder on the island but are no longer known to breed there.

Steller’s eiders are Arctic breeders. Most of the population nests in the Russian Arctic. A small part of the population nests along freshwater tundra ponds on Alaska’s Arctic coastal plain, especially near Utqiagvik. Historically, nesting also occurred in the coastal wetlands of the Yukon-Kuskokwim Delta, but nesting is rare there now.

The eiders typically arrive on their breeding grounds in pairs, having formed pair bonds for the season on the wintering grounds.

Studies at Utqiagvik have found that the breeding success of Steller’s eiders increases when brown lemmings are abundant. It is thought that the eggs and young of the eiders are preyed upon less by jaegers, gulls, ravens and foxes when lemmings are plentiful.

After the breeding season, Steller’s eiders from northern Alaska and Russia move south through the Bering Strait in a “molt migration,” gathering by the thousands in Nelson and Izembek Lagoons on the Alaska Peninsula to molt their flight feathers.

During this flightless period they forage in food-rich eelgrass beds of lagoons and shallow, sheltered, coastal waters and on tidal flats.

When the eiders regain flight, Alaska-nesting eiders move to wintering areas at Kodiak Island and along the Alaska Peninsula and Aleutian chain. They settle into bays and lagoons but also forage in deeper, sheltered waters.

Eel grass beds are an especially rich habitat for wintering Steller’s eiders, providing a diverse diet of marine invertebrates including a variety of crustaceans, marine worms, snails, clams and other shellfish.

In contrast to their scattered breeding distribution, Steller’s eiders are highly social in winter, forming large, single-species flocks. They tend not to mix with other sea duck species. Large flocks are probably a defense mechanism to avoid predation by large avian predators such as bald eagles and gyrfalcons.

The species is noted for spectacular foraging behavior of the large wintering flocks that dive in astonishing synchrony, creating a halo of spray.

Many northern seabirds are in decline, but limited data from the breeding and wintering grounds indicate Steller’s eiders are declining more dramatically than most, for unknown reasons. The Alaska breeding population is listed as threatened under the Endangered Species Act, and the Russian population has similar status in Russia.

Impacts of global warming on marine ecosystems are likely contributing to the eider’s decline. But there are other factors to consider, too.

Studies at Utqiagvik suggest lead poisoning from historical and current illegal use of lead shot may be impacting Steller’s eiders. On the Yukon-Kuskokwim Delta, lead poisoning was shown to cause significant mortality for spectacled eiders. Steller’s eiders use the same habitat, so lead poisoning may have contributed to their decline there.

Thanks to co-management agreements between federal, state and tribal governments for waterfowl management, the harvest of Steller’s eiders and their eggs is small in Alaska. However, that is not the case in Russia, where harvest and egging may occur at levels that could be impacting the population, especially when large numbers of eiders cluster in bad weather near settlements.

The Steller’s eider’s habit of forming huge flocks in a few critical areas, especially during the molt, is problematic for the species in the event of habitat loss or an oil spill. In 1973 a spill off the coast of Norway killed 2,500 Steller’s eiders.

As Russian oil tanker traffic increases through the Bering Strait, we hold our breath. A spill in the Bering Sea ecosystem, already challenged by climate change, would have tragic and long-lasting impacts on all life in Bering Sea waters and along its shores.

ARIES – Mar 21/Apr 20

You may have di culty reaching people this week, Aries. Whether it’s di culty getting attention or tech issues a昀ecting communication, use the situation as an opportunity to relax.

TAURUS – Apr 21/May 21

Taurus, a challenging project may lead you to throw yourself into work even more than usual over the course of the week. Remember to take time to exhale.

GEMINI – May 22/Jun 21

Visit someone in person if you are looking to catch up or have a meaningful conversation, Gemini. Skip impersonal text messages or social media posts and meet face-to-face.

CANCER – Jun 22/Jul 22

Unfortunate 昀nancial news may come your way, Cancer. Take the developments in stride and resolve to overcome them. Seek advice on how to do so, if necessary.

LEO – Jul 23/Aug 23

Leo, there is a strong desire for romance surrounding you. Whether you want to spice up a current relationship or are seeking a new one, this is the week to put out feelers.

VIRGO – Aug 24/Sept 22

Virgo, enjoy a unique chance to spend quality time with someone you love. Enjoy the experience in the moment and resolve to spend more time together.

LIBRA – Sept 23/Oct 23

An unexpected meeting with a friend and subsequent conversation could leave you feeling a little shaken, Libra. You will learn things that give you a new perspective.

SCORPIO – Oct 24/Nov 22

You could experience a desire to make sudden changes to your home life, work situation or even a relationship, Scorpio. Stagnation has set in, but now is not the time for big moves.

SAGITTARIUS – Nov 23/Dec 21

Sagittarius, if a message arrives from someone who lives far away, you may be prompted to hop in the car or on a plane and visit that person. An impromptu trip could be fun.

CAPRICORN – Dec 22/Jan 20

Look into all of the facts surrounding an o昀er to increase your income, Capricorn. It could be too good to be true, or it might be a legitimate deal. You need to sort things out.

AQUARIUS – Jan 21/Feb 18

Aquarius, this week you may encounter someone who is very interested in you. The resulting attention can be quite 昀attering. You’ll need to decide if it should go further.

PISCES – Feb 19/Mar 20

Situations that arise this week could have you feeling stressed, Pisces. Find ways you can separate yourself from certain situations that rile you up, even if it means a 昀ve-minute break.

Photo by Nick Hajdukovich BREEDING PLUMAGE – A flock of Steller’s eiders in breeding plumage is on their breeding ground near Utqiagvik where the majority of the Alaska population nests. Occasionally during spring migration, a few Steller’s eiders pass through Seward Peninsula coastal waters and the males can be seen decked out in their unmistakable, eye-catching finery. However, more often when this species is seen along the peninsula’s shores, they are nonbreeding birds in brown plumage similar to the brown females in this photo.

Photo by Nick Hajdukovich FLOCK IN FLIGHT IS QUITE A SIGHT – A flock of Steller’s eiders is flying over their breeding grounds near Utqiagvik. Steller’s eiders are smaller and more maneuverable in the air than their larger eider relatives. They are able to rise easily off the water without scampering over the surface, and can twist and turn more tightly in flight than their kin.

Photo by Kate Persons SIZE COMPARISON – Two female or juvenile, plain, brown Steller’s eiders are leading the way across the Safety Sound entrance below the Safety Bridge with a long-tailed duck in tow. Steller’s eiders are only slightly larger than long-tailed ducks and much smaller than spectacled, king and common eiders. Notice the distinctive flat-topped profile of the eider’s head.