Habitat
Long-tailed Jaegers breed in Arctic tundra, often far from the sea, sometimes in marshy or sedge-filled areas and other times in higher, drier spots such as small ridgelines. They also sometimes use areas with dwarf shrubs, as well as wind-scoured areas with patches of bare ground. They spend the nonbreeding season on the open ocean, from the Gulf Stream to the continental shelf break in oceans of the Southern Hemisphere off Australia, South America, and Africa.
Back to topFood
During summer, Long-tailed Jaegers depend largely on lemmings, particularly the collared lemming, and voles. These rodents can swell a hundredfold in population over a 4–5-year cycle, causing fluctuation in jaeger breeding success. They hunt lemmings from the air, by hovering into a headwind like a kestrel; or from the ground either by keeping a lookout from a rise, or by waiting at lemming warrens. Long-tailed Jaegers also eat young birds, insects, and berries in smaller amounts. Outside the breeding season, Long-tailed Jaegers pick fish and marine invertebrates (alive or dead) from the sea surface, or chase terns, gulls, and other seabirds to take their catch. They sometimes show up to feed on waste or discards from ships.
Back to topNesting
Nest Placement
They build their nests on the ground in the tundra, variously on low rises, gentle slopes, bare clay, gravel, or among dwarf shrubs.
Nest Description
The nest is a small depression on the ground without any lining.
Nesting Facts
| Clutch Size: | 1-2 eggs |
| Number of Broods: | 1 brood |
| Egg Length: | 2.0-2.4 in (5-6 cm) |
| Egg Width: | 1.4-1.6 in (3.5-4.2 cm) |
| Incubation Period: | 23-25 days |
| Nestling Period: | 1-2 days |
| Egg Description: | Greenish to olive brown or pale blue, with dark brown spots. |
| Condition at Hatching: | Downy and well developed, able to leave the nest in 1–2 days. |
Behavior
Long-tailed Jaegers are the most graceful and agile of the three jaeger species, although their flight is not as all-out fast as Parasitic Jaegers. They tend to have larger breeding territories than other jaegers, and they defend these against intruders using flight displays. These include calling at the offender while gliding with bowed wings, showing off their white wing patches, and flying slowly at the intruder with an exaggerated raising of the wings. Long-tailed Jaegers form pair bonds to breed, and often rejoin the same mate the next year. Both sexes help raise the young.
Back to topConservation
Long-tailed Jaegers breed in the high Arctic and their breeding numbers vary from year to year based on local conditions and fluctuating prey populations, making their numbers difficult to track. Partners in Flight estimates the global breeding population at 1.7 million. They score a 9 out of 20 on the Continental Concern Score, which means they are not on the Partners in Flight Watch List and are a species of low conservation concern.
Back to topCredits
Dunne, P. (2006). Pete Dunne's essential field guide companion. Houghton Mifflin Harcourt, New York, USA.
Mullarney, K., L. Svensson, D. Zetterström, and P. Grant (1999). Collins Bird Guide. HarperCollins Publications Ltd., London, United Kingdom.
Wiley, R. Haven and David S. Lee. (1998). Long-tailed Jaeger (Stercorarius longicaudus), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.