Redear Sardine, Harengula humeralis

Redear Sardine, Harengula humeralis. Fish caught from coastal waters off Boca Raton, Florida, March 2022. Length: 7.7 cm (3.0 inches). Catch, photograph and identification courtesy of Ben Cantrell, Sebastian, Florida.

Redear Sardine, Harengula humeralis. Fish caught off the Grand Mayan Pier, Riviera Maya, Cancun, February 2019. Length: 18 cm (7.0 inches). Catch, photograph and identification courtesy of George Brinkman, Guelph, Ontario, Canada.

Redear Sardine, Harengula humeralis. Fish caught from coastal waters off Key Largo, Florida, April 2019. Length: 18 cm (7.0 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.

Redear Sardine, Harengula humeralis. Fish caught from coastal waters off Key Largo, Florida, February 2019. Length: 18 cm (7.0 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).

The Redear Sardine, Harengula humeralis, is a member of the Herring or Clupeidae Family, that is also known as the Redear Herring, and in Mexico as sardinita de ley. Globally, there are four species in the genus Harengula, all of which are found in Mexican waters, three in the Atlantic Ocean and one in the Pacific Ocean.

The Redear Sardine has a fusiform moderately compressed body with convex upper and lower body profiles. They are an iridescent blue-green dorsally that transitions to silvery ventrally with 3 or 4 faint orange longitudinal lines on the sides and an orange spot behind the top corner of the fill cover. The dorsal fin has a black tip. The mouth opens at the front with the lower jaw slightly projecting. The anal fin has a short base and is well behind the dorsal fin with 15 to 19 rays; the caudal fin is forked; the dorsal fin has 17 to 20 rays and is located slightly before mid-body; and, the pelvic fins and are closer to the pectoral fin base than the anal fin origin and have 7 rays. They have 27 to 31 gill rakers. Their belly is covered with bony scales.

The Redear Sardine is a pelagic coastal species that form very large schools around coral reefs and over seagrass beds at depths up to 9 m (30 feet). They reach a maximum of 26.5 cm (10.4 inches) in length. They are active nocturnally being planktivores feeding on a variety or prey including amphipods, copepods, insect larvae, isopods, small mollusks, mysids and ostracods. In turn they play an important role as a food source which includes their eggs and larvae for a wide variety of marine fish, marine mammals, and sea birds. Reproduction is oviparous. They are fast growing but short lived. The Redear 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.

The Redear Sardine is a resident of all Mexican waters of the Atlantic Ocean including the Gulf of Mexico and the Caribbean.

The Redear Sardine is most likely confused with the False Pilchard, Harengula clupeola and the Scaled Sardine, Harengula jaguana, both of which have a small black spot on the upper corner of the gill cover.

From a conservation perspective the Redear Sardine is currently considered to be of Least Concern with stable, widely distributed populations. They are caught with purse seines, beach seines, floating gill nets and cast nets and sold commercially. They are utilized as a live bait fish and also marketed fresh for human consumption and utilized in fish meal.