The green sturgeon is a long-lived, slow growing, species that spends most of its adult life at sea, primarily in nearshore oceanic waters, bays, and estuaries--although, as juveniles, they spend 1-4 years in freshwater or in estuaries (McPhail 2007, NOAA Fisheries 2010
). This species is usually dark green in colour on the back and flanks, and sports a "midventral dark, arro-like stripe on the belly that is a useful field character." (McPhail 2007). Although green sturgeon are classified as bony fish, the skeleton is mostly comprised of cartilage (NOAA Fisheries 2010). This species lacks scales, but has five rows of bony plates on the body (NOAA Fisheries 2010).
NOAA Fisheries (2010) provides the following reproduction information: "Early life-history stages reside in fresh water, with adults returning to freshwater to spawn when they are more than 15 years of age and more than 4 feet (1.3 m) in size. Spawning is believed to occur every 2-5 years (Moyle, 2002). Adults typically migrate into fresh water beginning in late February; spawning occurs from March-July, with peak activity from April-June (Moyle et al., 1995). Females produce 60,000-140,000 eggs (Moyle et al., 1992)."
McPhail (2007) reports that once they leave their spawning streams, green sturgeon migrate rapidly northwards, and likely travel in schools. Diet of adults includes shrimp, mollusks, amphipods, and small fish (NOAA Fisheries 2010).
The Committee on the Status of Wildlife in Canada (COSEWIC) list this species as "special concern". In British Columbia, it is illegal to keep green sturgeon and catches must be returned alive to the water.
Read the NOAA Fisheries (2010) page on this species for additional detailed information.