Species: Thalasseus elegans

Elegant Tern
Species
Birds

This is an approximately 43-cm-long bird with long pointed wings (span about 86 cm), a forked tail, and a long, thin, reddish orange (adults) to yellow (some juveniles) bill; underside of primaries is mostly pale; breeding adult is pale gray above, with black crown, nape, and crest, and white below, often with a pinkish tinge; winter adult and juvenile have white forehead, and the black on the crown extends forward around the eye; juveniles has variable dark mottling on the upperparts, may have orange legs; some juveniles have relatively little black on the crown as in juvenile royal tern (NGS 1983).

Kingdom
Animalia
Phylum
Craniata
Class

Aves

Order

Charadriiformes

Family

Laridae

Genus

Thalasseus

Natureserve Explorer
Source:
ELEMENT_GLOBAL.2.103610
Classification
Other Global Common Names
Charrán Elegante - Sterne élégante
Informal Taxonomy
Animals, Vertebrates - Birds - Other Birds
Formal Taxonomy
Animalia - Craniata - Aves - Charadriiformes - Laridae - Thalasseus - but separated on the basis of genetic data that correspond to plumage patterns (Bridge et al. 2005).

This is an approximately 43-cm-long bird with long pointed wings (span about 86 cm), a forked tail, and a long, thin, reddish orange (adults) to yellow (some juveniles) bill; underside of primaries is mostly pale; breeding adult is pale gray above, with black crown, nape, and crest, and white below, often with a pinkish tinge; winter adult and juvenile have white forehead, and the black on the crown extends forward around the eye; juveniles has variable dark mottling on the upperparts, may have orange legs; some juveniles have relatively little black on the crown as in juvenile royal tern (NGS 1983).

Short General Description
A smallish, gray, black, and white seabird.
Migration
false - false - true
Non-migrant
false
Locally Migrant
false
Food Comments
These terns dive into water to obtain fishes and shrimps. In the San Diego, California, area, the diet of chicks is mostly northern anchovy; age class of anchovies in diet overlaps with that taken in commercial fishery (Schaffner 1986).
Reproduction Comments
Eggs are laid between early April and early June. Clutch size usually is 1, sometimes 2. Incubation lasts probably about 20 days. Fledging occurs in early June-late July (Schaffner 1986). Individuals first breed probably no earlier than their third summer; longevity is unknown, but individuals likely are long lived (Burness et al. 1999).
Ecology Comments
Productivity is strongly correlated with northern anchovy abundance (Schaffner 1986).<br><br>Western and ring-billed gulls may destroy all eggs in a colony and cause a shift to a new nesting site (Schaffner 1986).
Length
43
Weight
257
NatureServe Global Status Rank
G2
Global Status Last Reviewed
2009-02-03
Global Status Last Changed
1997-02-05
Other Status

NT - Near threatened

Conservation Status Map
<img src="http://www.natureserve.org/explorer/servlet/GetMapGif?US.CA=S1&US.NM=SNR&US.WA=__" alt="Conservation Status Map" style="width: 475px; height: auto;" />
Global Range
Nesting range encompasses the Pacific coast from southern California south to central Baja California, Gulf of California islands, Mexico. Currently, five known breeding colonies exist: Isla Rasa, Gulf of California, Mexico (Clapp et al. 1993 cited in Burness et al. 1999); Western Salt Company, south San Diego Bay, California (has also attempted nesting elsewhere at San Diego Bay); Bolsa Chica Ecological Reserve, Orange County, California (since 1987, Collins et al. 1991); Isla Montague in the Colorado River Delta, Gulf of California; and Los Angeles Harbor (since 1998). Nesting formerly may have extended southward to Honduras (see Burness et al. 1999). Summer nonbreeders occur along Pacific coast primarily from central California south to Costa Rica (Howell and Webb 1995, AOU 1998).<br><br>During the nonbreeding season most birds are in South America, along the Pacific coast mainly from Ecuador to central Chile, with small numbers northward to central Mexico (Howell and Webb 1995, AOU 1998, Burness et al. 1999). After breeding, individuals disperse northward along the Pacific coast as far as northern California (and sometimes to northern British Columbia) (Burness et al. 1999).
ELEMENT_GLOBAL.2.103610