Atlantic Bonito

Atlantic Bonito, Sarda sarda

Atlantic Bonito, Sarda sarda. Fish caught from coastal waters off Manasquan, New Jersey, September 2014. Length: 41 cm (16 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).

Atlantic Bonito, Sarda sarda. Fish caught from coastal waters off Point Pleasant, New Jersey, September 2014. Length: 56 cm (22 inches). Weight: 1.4 kg (3.1 lbs). Catch, photograph, and identification courtesy of Kenneth Tse, Toronto, Canada.

The Atlantic Bonito, Sarda sarda, is a member of the Mackerel or Scombridae Family, that is also known as the Common Bonito and in Mexico as bonito del Atlántico. Globally, there are four species in the genus Sarda,  of which three are found in Mexican waters, one in the Atlantic and two in the Pacific Ocean.

The Atlantic Bonito has an elongated, rounded, fusiform, thick, stout, and tuna-like body with a depth that is 23% to 27% of standard length and is designed aerodynamically for speed. They are steely blue dorsally transitioning to silver ventrally with 5 to 11 narrow dark blue bands running slightly obliquely downward and forward across their lateral line. Their anal and pelvic fins are white; their caudal fin is dark gray; their dorsal fins are dusky with the second fin having a white tip; and their pectoral fins are gray. Their head has a moderately large mouth that ends at the rear margin of the eyes and is equipped with prominent large conical teeth. Their anal fin has 14 to 17 rays with a short base and is deeply concave, and is followed by 7 finlets; their caudal fin is lunate, is much broader than long, and has 1 large and 2 small keels on its base; their first dorsal fin has 20 to 23 spines; their second dorsal fin has 15 to 18 rays, is deeply concave and closely follows the first dorsal fin, and is followed by 8 finlets; and, their pectoral and pelvic fins are similarly shaped and small in stature. They have 16 to 23 gill rakers on their first arch. They are covered with minute scales. Their lateral line is prominent and wavy.

The Atlantic Bonito is a common inhabitant of shallow waters, being epipelagic and neritic that is normally found at depths up to 200 m (660 feet). They are also known to enter estuaries. They reach a maximum of 1.02 m (3 feet 4 inches) in length and 11 kg (24 lbs) in weight and known for being fast growing. As of January 1, 2023, the International Game Fish Association world record stood at 60 cm (2 feet 0 inches), with the fish caught off Massachusetts in September 2020. They are typically found in waters between 12oC (54oF) and 27oC (81oF). At sea they form large schools and jump out of the water in pursuit of prey. They prey on small schooling fish and invertebrates including shrimp and squid; they are also known to be cannibalistic. Reproduction is oviparous and involves pelagic eggs and larvae. They have lifespans of up to five years. The Atlantic Bonito 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.

The Atlantic Bonito is a resident of Mexican waters of the Atlantic Ocean being found throughout the Gulf of Mexico; they are absent from along the east coast of the Yucatán Peninsula in the Caribbean.

The Atlantic Bonito can be confused with the Skipjack Tuna, Katsuwonus pelamis (4 to 6 dark horizontal stripes on belly) and the Striped Bonito, Sarda orientalis (horizontal stripes; mouth more than half the head length).

From a conservation perspective the Atlantic Bonito is currently considered to be of Least Concern with stable, widely distributed populations. They are caught commercially with various types of nets, by hook and line, and as a by-catch of tuna fishermen trolling for bigger game. On a global basis they are caught at annual levels of 80,000 tons of which 5% is taken from Mexican waters. They are a significant recreational angler foe and known for their strength and endurance. They are also used as bait. They are considered a quality food fish and sold fresh, dried, salted, smoked, canned, and frozen but are considered inferior to tuna. They are reported to contain ciguatoxin. Note: commercially sold canned Bonito del Norte is actually Albacore Tuna.