Aves | Ciconiiformes
Environment: milieu / climate zone / depth range / distribution range
Circumglobal. Tropical to polar.
Length at first maturity / Size / Weight / Age
Maturity: Lm ?  range ? - ? cm Max length : 38.0 cm TL male/unsexed; (Ref. 8812); max. published weight: 110.00 g (Ref. 356)
Culmen: 3.35 cm; tarsus: 1.69 cm; wing: 27.0 cm.
Total Length: 33 to 38 cm; Wingspan: 79 to 81 cm (Ref. 8812). Coastal (Ref. 356), found in the beach, shoreline, and pelagic zone (Ref. 116102). Displays surface plunging and dipping (Ref. 356). "Erect" and "sky-pointing" display as an appeasement posture during nesting and in pairing. High level of territorial aggression during pre-incubation and hatching periods. European Starlings (Sturnus vulgaris) and Ruddy Turnstones (Arenaria interpres) feed on its eggs. Colonial behavior as an anti-predatory tactic by confusing or intimidating its predator. Ruddy Turnstones (A. interpres) steal fish delivered by parents of young birds in colonial nesting sites. Surface feeder. Moves across the great distance from the polar northern hemisphere to the southern polar region to feed after the breeding season; when feeding, tend to spread out pelagically instead of in groups. 1988 La Niña event linked to fledging failure on Mousa Island off Scotland (Ref. 87784).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Lepage, D. 2007. (Ref. 7816)
IUCN Red List Status (Ref. 123251)
CITES status (Ref. 108899)
Threat to humans
| FishSource |
Estimates of some properties based on models
): 0.4 - 13.3, mean 6.8 (based on 2468 cells).
Low to moderate vulnerability (28 of 100)