Elegant Tern
Elegant Tern
Thalasseus elegans
At a Glance
Formerly just a late-summer visitor to our Pacific Coast from its Mexican breeding colonies, the Elegant Tern has been reaching California in increasing numbers since about 1950, nesting there since 1959. A medium-sized tern, slim and long-billed, strictly coastal in its occurrence. In size, shape, and callnotes, very similar to the Sandwich Tern of the Atlantic Coast.
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
Near Threatened
Habitat
Coasts and Shorelines, Open Ocean, Saltwater Wetlands
Region
California, Northwest
Behavior
Direct Flight, Swooping
Population
180.000
Range & Identification
Migration & Range Maps
Moves north along coast to northern California or farther in late summer and early fall, after breeding. Most move south again in October. Winter range extends as far south as Peru and northern Chile. Very rarely strays inland, but perhaps somewhat more likely in the interior than Royal Tern.
Description
16-17" (41-43 cm). Very similar to Royal Tern. Smaller (apparent only when they are together). Has much slimmer bill that often looks slightly droopy. In "winter" plumage (worn for most of year), black from nape usually extends forward to include the eye on Elegant, not on Royal Tern.
Size
About the size of a Crow, About the size of a Mallard or Herring Gull
Color
Black, Gray, Orange, White
Wing Shape
Long, Pointed, Tapered
Tail Shape
Forked, Long, Notched, Pointed
Songs and Calls
A loud grating kar-eek.
Call Pattern
Falling, Flat
Call Type
Rattle, Trill
Habitat
Coast, bays, beaches. Generally on ocean, close to shore over shallow waters, concentrating around bays and estuaries. Sometimes far out to sea. Extremely rare on fresh waters inland. Nests on sandy or rocky islands.
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Behavior
Eggs
One, rarely 2. Buff to white, blotched or spotted with dark brown. Incubation is probably by both parents; incubation period not well known, but more than 20 days.
Young
May leave nest after a few days, gather in group (called a "creche"). Both parents probably feed young. Age at first flight and at independence not well known.
Feeding Behavior
Forages by flying over water, hovering and plunge-diving to catch prey below the surface.
Diet
Small fish. Feeds mostly on small fish, probably also taking some small crustaceans. In California waters, preys heavily on northern anchovy; increasing population of anchovies there coincided with increase in Elegant Terns.
Nesting
Breeds in colonies. Sometimes associated with other terns (or, in Mexico, with Heermann's Gulls). In California, appears to prefer nesting close to the larger Caspian Terns, which may help in defense against predators. Courtship displays on ground involve both members of pair drooping wings, stretching neck upward, raising and lowering bills. Nest site is on open bare ground. Nest (probably built by both sexes) is a simple scrape in the soil.
Climate Vulnerability
Conservation Status
Has increased and spread northward in California in recent years, first nesting at San Diego in 1959 and in Orange County in 1987. At the same time, has disappeared from some former nesting sites in western Mexico. Considered vulnerable because nesting is restricted to very few sites.