Jack silverside

Atherinopsis californiensis, the jack silverside or jacksmelt, is a species of neotropical silverside native to the Pacific coast of North America from Oregon, United States to southern Baja California, Mexico. This species often grows to 49 cm (19 in), but specimens of 55 cm (22 in) in total length have been reported. It is silver throughout the body, with a grey dorsal pattern, and a light silver ventral-lateral, as well as a yellow spot present behind the eye, on the operculum. and is important commercially as a source of human food. It is the only known member of its genus. They are commonly confused with the Atherinops affinis, the topsmelt silverside.

Atherinopsis californiensis is a key element of Pacific coast marine ecosystems. This circumscription reveals its ability to adapt to changing environmental conditions across its distribution in different habitats. The diet and reproductive strategies of Jacksmelt are important to understanding its ecological role in these ecosystems. Additionally, it is recognized that this species has economic value and the need is for sustainable practices to maintain abundance. Conservation efforts to proactively maintain healthy populations of Atherinopsis californiensis that are not chipped, will be important due to continuing threats of overfishing and habitat degradation.