Long-tailed Jaeger
Long-tailed Jaeger
Stercorarius longicaudus
At a Glance
A swift-flying seabird, extremely graceful and agile in flight. When swimming, it floats buoyantly, and it takes flight from the water easily. Of the three jaeger species, the Long-tail is the smallest and the one that migrates farthest offshore; south of the Arctic, it seldom comes within sight of land.
All bird guide text and rangemaps adapted from by Kenn Kaufman漏 1996, used by permission of Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Category
Gull-like Birds, Gulls and Terns
IUCN Status
Least Concern
Habitat
Lakes, Ponds, and Rivers, Open Ocean, Tundra and Boreal Habitats
Region
Alaska and The North, California, Eastern Canada, Florida, Great Lakes, Mid Atlantic, New England, Northwest, Southeast, Southwest, Texas, Western Canada
Behavior
Direct Flight, Hovering, Swimming
Population
1.700.000
Range & Identification
Migration & Range Maps
Typically migrates farther offshore than other jaegers. In early fall, a very few (mostly first-autumn immatures) show up on lakes well inland. Fall migration earlier than in other jaegers, with many adults southbound by mid-August. Wintering areas not well known, but apparently mostly at sea south of the Equator.
Description
21" (53 cm). Adult has very long, pointed central tail feathers. Plumage less variable than other jaegers, with white chest, neat black cap, blue-gray back. Juvenile in first fall grayish brown, with whitish barring. Later immature stages quite variable.
Size
About the size of a Crow, About the size of a Mallard or Herring Gull
Color
Black, Brown, Gray, Tan, White, Yellow
Wing Shape
Long, Narrow, Pointed, Tapered
Tail Shape
Long, Pointed, Square-tipped, Wedge-shaped
Songs and Calls
A harsh kreeah; other yelping and rattling notes on breeding grounds.
Call Pattern
Flat, Simple
Call Type
Scream
Habitat
Open sea; tundra (summer). Spends much of year far out at sea, generally out of sight of land. In breeding season on tundra, both near coast and well inland, but tends to prefer higher and drier areas rather than marshy coastal tundra. Young birds and non-breeders may remain at sea all year.
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Behavior
Eggs
2, sometimes one, rarely 3. Brown to olive, blotched darker brown and gray. Incubation is by both sexes, 23-25 days.
Young
Both parents feed young, by regurgitation. Parents defend nest by diving at predators or humans, even landing on intruder's head and pecking. Young can fly at 22-27 days; remain with parents another 1-3 weeks.
Feeding Behavior
In summer on tundra, hunts by hovering and then swooping down on prey; sometimes picks up items while swimming, or catches insects in flight. May steal food from other birds.
Diet
Includes fish, rodents, birds, berries. Summer diet is mostly small rodents, especially lemmings and voles when they are in high population cycle; also insects, small birds, fish, squid, carrion, and berries (especially crowberries). Diet during rest of year poorly known; includes fish, carrion, refuse.
Nesting
Probably does not breed until at least 3-4 years old. More likely to nest successfully in years when lemmings are abundant. Has spectacular courtship flight, with rapid swoops and zigzags, often three birds together, or one male chasing one female. In courtship on ground, male feeds female. Nest site is on ground on open tundra, often on slightly raised spot. Nest (built mostly by female?) is simple depression, usually with sparse lining of plant material.
Conservation
Conservation Status
Local breeding populations fluctuate sharply with changes in food supply; overall numbers probably more or less stable. No evidence of widespread trends in population.
Climate Threats Facing the Long-tailed Jaeger
Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.