Pacific Sardine

Pacific Sardine, Sardinops sagax

Pacific Sardine, Sardinops sagax. Fish provided by the commercial fishermen of Puerto Los Cabos, Baja California Sur, March 2006. Length: 10 cm (3.9 inches). Uncommon to the greater Los Cabos area.

Pacific Sardine, Sardinops sagax. Fish caught from coastal waters off Loreto, Baja California Sur, June 2022. Length: 16 cm (6.3 inches). Catch, photograph and identification courtesy of Chris Wheaton, Fullerton, California.

Pacific Sardine, Sardinops sagax. Fish caught from coastal waters off Santa Cruz, California, June 2015. Length: 18 cm (7.1 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).

The Pacific Sardine, Sardinops sagax, is a member of the Herring or Clupeidia Family, that is also known as the California Pilchard and the South American Pilchard (which is a subspecies), and is known in Mexico as sardina monterrey. There are two global members of the genus Sardinops, one of which is found in Mexican waters, this species from the Pacific Ocean.

The Pacific Sardine has a slender elongated rounded fusiform body with a depth that is 17% to 21% of standard length. They are blue dorsally, silvery on their sides, and white ventrally. They have a row of black spots on their sides allowing for easy identification. They have a relatively large oblique mouth that opens at the front and reaches the center of their eyes. Their anal fin has a short base with 13 to 21 spines and originates well behind the dorsal fin; their caudal fin is forked; their dorsal fin is located mid-body with no spines and has 12 to 23 rays; and, their pelvic fins are under the rear of the dorsal fin. They have very short gill rakers.

The Pacific Sardine is a pelagic coastal schooling species that are found in large schools on the surface in the surf zone at depths up to 385 m (1,260 feet) with water temperatures ranging form 16oC (61oF) to 23oC (73oF) in the summer and 10oC (50oF) to 18oC (64oF) in the winter. They reach a maximum length of 41 cm (16 inches). They feed on planktonic crustaceans and phytoplankton; young fish feed on zooplankton such as copepods. Reproduction is oviparous with batch fecundities of ranging from 10,000 eggs to 45,000 eggs with larger females having more eggs, with the eggs and the larvae being pelagic. They have lifespans of 12 to 15 years. The Pacific Sardine is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

In Mexican waters the Pacific Sardine is a resident of the Pacific being found along both coasts of Baja and along the coast of the mainland as far south as Puerto Vallarta, Jalisco.

The Pacific Sardine is a straightforward identification that is not easily confused with any other species.

From a conservation perspective the Pacific Sardine is currently considered to be of Least Concern, with stable, widely distributed populations. They are heavily fished commercially. In 2000, they were the number one commercial catch of Mexico with 460,000 tons collected. They are the major fish processed in the large fish processing plant in Puerto Adolfo Lopez Mateos, Baja California Sur, where they are canned for human consumption. They were abundant in California waters until the 1970s when they virtually disappeared. Their populations have remained large and consistent in central and southern Baja California and in the Midriff Island area of the Sea of Cortez. They can be found up to 150 miles from shore and travel in schools that contain hundreds of thousands to millions of individuals. They migrate annually between feeding and spawning sites located at distances of 600 miles from each other. They are a mainstay of the diets of the Elegant Tern and the Heermann’s Gull. Each year 500,000 Elegant Terns and Heermann’s Gulls gather for nesting on Isla Rasa in the Central Gulf and consume about 65 tons of these sardines every day.