Biology

Sturgeons are most closely related to paddlefishes, reedfishes, and numerous fossil groups within the infraclass Chondostei that are primary cartilaginous fish with some degree of bonny structures (ossicification). They are not ancestral to modern bony fishes, but represent a highly  specialized and successful offshoot of ancestral Chondosteans. Their skeleton is composed  of cartilage, and they have a series of external bony plates, called scutes along their backs and sides. Sturgeon are often likened to sharks because of the many features they share, including spiracles, heterocercal tails, fin and jaw structure, spiral valve and Ampullae of Lorenzini (special sensing organs forming a network of jelly-filled pores). These unique sensory organs allow them to detect electrical signals given off by prey in murky waters and substrates. Sturgeon do not have teeth, but instead use their long, flexible "lips" to suck food up from the bottom.

Green Sturgeon were first described in San Francisco Bay in Ayres in 1857. Like most sturgeon they are anadromous, but tend to spend more time in the ocean than most species.  They can be found from Alaska to Mexico, but are most commonly encountered north of Point Conception.  Olive green coloration, barbell placement, differences in number and sharpness of scutes, and presence of an additional scute behind the dorsal and anal fins distinguish them from the co-occurring white sturgeon.

For more information, contact NOAA Fisheries Green Sturgeon Recovery Coordinator Joe Heublein at joe.heublein@noaa.gov or 916.930.3719.