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Threatened Eiders of North America Byram L. Feltner Bio 586

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Threatened Eiders of North America. Byram L. Feltner Bio 586. Eiders of North America (4 species). Common Eider King Eider Spectacled Eider (Threatened) Steller’s Eider ( Threatened ). Eider Characteristics. Large diving ducks (some can dive to depths of 180 feet) - PowerPoint PPT Presentation

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Threatened Eiders of North America

Byram L. FeltnerBio 586

Eiders of North America(4 species)

•Common Eider•King Eider•Spectacled Eider (Threatened)

•Steller’s Eider (Threatened)

Eider Characteristics

• Large diving ducks (some can dive to depths of 180 feet)

• Feed mainly on mollusks and invertebrates. Some diets can consist of some plant matter (rarely exceeds 5%).

• Found in extreme northern habitats. (Some spend the winter in openings of the sea ice.)

Nesting

• Typically line nest w/ down feathers

• Usually nest near rocky areas above water.

ClassificationKingdom: Animalia

Phylum: ChordataClass: Aves

Order: AnseriformesSuborder: AnseresFamily: AnatidaeSubfamily: AnatinaeTribe: Mergini

Common EiderSomateria mollissima

• Largest duck in North America (Length: 17”, Wingspan: 41”)

• Feed primarily on mollusks

• Population: 1-1.5 million

Common Eider Range

King EiderSomateria spectabilis

• Large Duck (Length: 16”, Wingspan: 37”)

• Feeds primarily on mollusks

• Population: <1 million

King Eider Range

Spectacled EiderSomateria fischeri

• Threatened Species• Large Duck (Length: 15”,

Wingspan: 36”)

• Diet varies according to time of year.

• Population: <100,000

Spectacled Eider Identification

• Identification Tip:– Bill feathered to nostril

• Adult male: – Pale green head with large

white patch around eye – Yellow bill – Black underparts – White upperparts

• Adult female: – Dark brown plumage with fine

black barring – Pale brown patch around eye

• Similar species: – The male is very distinctive. The female may be mistaken for

another eider female, but the eye patch and extensive feather on the bill sets it apart.

Spectacled Eider Diet

• Breeding/Growth Season– Insects and Vegetation

• Rest of Season– Mollusks and Vegetation

Threatened Listing

• Effective Date: June 9, 1993– Populations had declined by 94-98%

within the principle breeding range.• Alaska’s population declined 14% the

following year (1994).

Steller’s EiderPolysticta stelleri

• Threatened Species• Smallest of Eiders

(Length: 12”, Wingspan: 29”)

• Feeds mainly on crustaceans (amphipods, isopods, and barnacles)

• Population: 150,000 – 200,000

Steller’s Eider Identification• Identification Tips:

– Gray unfeathered bill – Squarish head – Long tail

• Adult male alternate: – White head and flanks – Black on throat and back – Black around eye – Greenish patch on lores and rear of head – Black spot on breast – Black and white scapulars – Brownish belly

• Adult female: – Dark brown plumage – Pale eyering – Square head

• Similar species: – Male is distinct. The female could be missidentified as

another eider. The female Steller’s has and unfeathered bill, squarer head, longer tail, and is smaller in size.

Steller’s Eider Diet

• Throughout Year– Mainly on various crustaceans (amphipods,

isopods, barnacles)

Threatened Listing

• Effective Date: 1997– Alaskan breeding populations has nearly

disappeared. • Estimates range from hundreds to low

thousands.• Problem not well understood.

Cause for Listing(Steller’s and Spectacled)

1. Destruction, Modification, or Curtailment of Habitat or Range

2. Over utilization for Commercial, Recreational, Scientific, or Educational Purposes

3. Disease or Predation4. Inadequacy of Existing Regulatory

Mechanisms5. Other Natural or Manmade Factors

1. Destruction, Modification, or Curtailment of Habitat

• Destruction of habitat is low.–Many areas unaltered and uninhabited

• Alaskan North Slope–Altered by oil and gas development–Only small portion of breeding range

• Marine habitat still poorly understood• Persistent Organic Pollutants (POPs).

Elevated concentrations of many trace elements, noticeably cadmium, selenium, and copper, but these were below levels associated with toxicological risk to marine birds.

2. Overutilization for Commercial, Recreational, Scietific, or

Educational Purposes

• Were traditionally harvested during migration

• Alaskan and Siberian natives– Take eggs and birds for food

• Skin and feathers used for clothing. • Bones used for household purposes• Feathers were used in fans for tourists• Spring harvest supplied traditional source of

meat to coastal communities.• Illegal harvest for taxidermy trade

– Magnitude unknown

3. Disease and Predation

• Increases in fox and common raven populations.– Never proven to have affected populations.

• Gull (glaucous-winged) populations increased due to fish processing wastes.– Prey on chicks

• Parasites (acanthocephalans) – Lowering reproduction/survival.– Not affected in good habitat.

4. Inadequacy of Existing Regulatory Mechanisms

• Harvest was regulated under authority of the Migratory Bird Treaty Act (16 U.S.C. 703-711).– Hunting has been closed since 1991

• Historically hunted in Russia– Estimates for harvest is high

• No records of harvest was recorded in Russia

• Hunting was not regulated strictly despite the M.B.T. (Prohibited hunting between March 10 and September 1)– This was due to the fact that many residents

historically and traditionally took eiders for food.

5. Natural or Manmade Factors

• Oil Spills• Oil Fields

– Low nesting numbers in active fields

• Pollution– From offshore oil development and fishery

vessels

• Fishing Nets• Lead shot

– Very few cases

• Severe weather– Natural die off

Conservation Measures Taken

1. Recognition2. Recovery Actions3. Requirements for Federal Protection4. Prohibition against certain practices

1. Recognition

• Encourages and results in conservation actions by Federal, State, and local governments and private agencies, groups and individuals.

2. Recovery Actions

• Act provides for possible land acquisition and cooperation with the states and requires that recovery actions be carried out for all listed species.

• Land isn’t always secured!– The spectacled eider is one of the many migratory

species that depend on the globally unique habitat at Teshekpuk Lake inside the National Petroleum Reserve-Alaska along Alaska's western Arctic coast. The area is also critical to Pacific black brant, yellow-billed loons, tundra swans, king eiders, and northern pintails. But the Bush administration wants to lease the lands along Teshekpuk Lake to the oil and gas industry.

3. Requirements for Federal Protection

• Prohibits taking and harm of the listed species.• Provided habitat protection rather than just

species protection that was covered in the M.B.A.

4. Prohibition against certain practices

• Scientific studies– Permit system

• Zoological exhibition, educational purposes– Permit system

• No threatened species on exhibit

Como Zoo, MN

Importance

• Balance– Keystone species

• Specific niche

Ten Most Wanted

1. Spectacled Eider2. Ross’s Gull3. Ivory Gull4. White morph Gyrfalcon5. Snowy Owl6. Albatross7. White-tailed Tropicbird 8. Atlantic Puffin9. Trogon10. Ivory-billed Woodpecker

Most Wanted