E-Fauna BC: Electronic Atlas of the Wildlife of British Columbia

Bothragonus swanii (Steindachner, 1876)
Rockhead
Family: Agonidae

Source: Distribution of Bothragonus swanii as compiled by Aquamaps

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Species Information

Dorsal spines (total): 2 - 5; Dorsal soft rays (total): 4 - 5; Anal spines: 0; Anal soft rays: 4 - 5; Vertebrae: 32. Dorsal fins small; caudal fin rounded; pectoral fins large, supported well out from sides of body; pelvic fins very narrow and rays appear fused (Ref. 6885). Color very variable, depending on background; brown with dark bars, orange with bluish bars, or scarlet with brown bars (Ref. 6885).

Source: FishBase. Kanayama, T. 1991 . (Ref. 28197)

Biology

Species Biology

Inhabits intertidal areas and to 18 m depth (Ref. 2850). Frequently caught in tide pools (Ref. 28197). Its food consists mainly of tiny crustaceans (shrimp and crab-like creatures) which are picked from the bottom or very close to it (Ref. 4930). Demersal spawner in nearshore habitats (Ref. 56049). demersal; marine; depth range 0 - 18 m (Ref. 2850). Temperate.

Source: FishBase. Kanayama, T. 1991 . (Ref. 28197)

Distribution

Eastern Pacific: Kodiak Island, Alaska to Carmel Bay, Monterey County, California, USA (southernmost range confirmed by J.R. Wolfe, pers. Comm. 09/02).

Source: FishBase. Kanayama, T. 1991 . (Ref. 28197)

Status Information

Origin Status	Provincial Status	BC List (Red Blue List)	COSEWIC
Native	SNR	No Status	Not Listed

BC Ministry of Environment: BC Species and Ecosystems Explorer--the authoritative source for conservation information in British Columbia.

Taxonomic and Nomenclatural Links

Genetic and lineage information (NCBI Taxonomy Browser)

Additional Range and Status Information Links

NatureServe Explorer
University of Alaska Museum

Additional Photo Sources

Flickr Image Search
Google Image Search
Images from Calphoto

Related Databases

fishbase

General References

FishBase References
Google Scholar Search

Recommended citation: Author, Date. Page title. In Klinkenberg, Brian. (Editor) 2021. E-Fauna BC: Electronic Atlas of the Fauna of British Columbia [efauna.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed: 2025-05-21 8:00:31 AM]

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