Larus occidentalis, Western gull
Advertisement

You can sponsor this page

Larus occidentalis   Audubon, 1839

Western gull
Upload your photos 
 Google image |

No photo available for this species.
No drawings available for Laridae.

Classification / Names Common names | Synonyms | CoL | ITIS | WoRMS

Aves | Charadriiformes | Laridae

Environment: milieu / climate zone / depth range / distribution range Ecology

Others.  Temperate

Distribution Countries | FAO areas | Ecosystems | Occurrences | Introductions

Eastern Pacific and Western Atlantic. Subtropical to temperate.

Length at first maturity / Size / Weight / Age

Maturity: Lm ?  range ? - ? cm Max length : 68.0 cm TL male/unsexed; (Ref. 8812); max. published weight: 1.0 kg (Ref. 356)

Short description Morphology

Culmen: 5.56 cm; tarsus: 7.197 cm; wing: 41.2 cm.

Biology     Glossary (e.g. epibenthic)

Total Length: 61 to 68 cm; Wingspan: 132 to 142 cm (Ref. 8812). Occupies the continental shelf; <80 km (Ref. 356). Scavengers; exhibits kleptoparasitism (Ref. 356). Opportunistic feeders that eat a wide variety of food. Based on stable isotope analysis (SIA) diet study of egg albumin, belongs to lower N signature group (based on ratios of stable isotopes of nitrogen and carbon) indicating a more planktivorous diet. Switch in diet from garbage to fish when chicks hatch for its higher nutritional content to assure higher fledging success. Early breeding and early egg-laying assures higher fledging success for this species. On the Farallon Islands, California, high nest failures recorded during ENSO (El Niño) events; severe events in 1982-1983 causing adult mortality. (Ref. 87784).

Life cycle and mating behavior Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae

Main reference References | Coordinator | Collaborators

Schreiber, R.W. 1970 Breeding biology of Western gulls (Larus occidentalis) on San Nicolas Island, California, 1968. The Condor 72:133-140. (Ref. 80153)

IUCN Red List Status (Ref. 130435: Version 2025-1)

  Least Concern (LC) ; Date assessed: 08 August 2018

CITES status (Ref. 108899)

Not Evaluated

CMS (Ref. 116361)

Not Evaluated

Threat to humans

Human uses


| FishSource |

Tools

E-book | Field guide

More information

Trophic Ecology
Food items (preys)
Diet composition
Food consumption
Predators
Ecology
Ecology
Population dynamics
Growth
Max. ages / sizes
Length-weight rel.
Length-length rel.
Length-frequencies
Mass conversion
Abundance
Life cycle
Reproduction
Maturity
Fecundity
Spawning
Eggs
Egg development
Larvae
Distribution
Countries
FAO areas
Ecosystems
Occurrences
Introductions
Physiology
Oxygen consumption
Human Related
Stamps, coins, misc.
Outreach
Collaborators
Taxonomy
Common names
Synonyms
Morphology
Pictures
References
References

Internet sources

BHL | BOLD Systems | CISTI | DiscoverLife | FAO(Publication : search) | Fishipedia | GenBank (genome, nucleotide) | GloBI | Gomexsi | Google Books | Google Scholar | Google | PubMed | Tree of Life | Wikipedia (Go, Search) | Zoological Record

Estimates based on models

Preferred temperature (Ref. 115969): 5.4 - 18.5, mean 8.3 (based on 112 cells).
Resilience (Ref. 69278): High, minimum population doubling time less than 15 months (K=16.74-39.08).
Fishing Vulnerability (Ref. 71543): Moderate to high vulnerability (47 of 100).
Price category (Ref. 80766): Unknown.

Comments & Corrections
Back to Search
Random Species
Back to Top