Barred Flagtail

Barred Flagtail, Kuhlia mugil

Barred Flagtail, Kuhlia mugil. Fish caught in coastal waters off St. Lucia, South Africa in March 2019. Length: 10 cm (3.9 inches). Catch, photograph, and identification courtesy of Josh Leisen (joshadventures.com), Gaylord, Michigan.

Barred Flagtail, Kuhlia mugil. Fish caught in coastal waters off St. Lucia, South Africa in March 2019. Length: 15 cm (5.9 inches). Catch, photograph, and identification courtesy of Ben Cantrell, San Diego, California.

Barred Flagtail, Kuhlia mugil. Fish caught from the jetty at Cabo San Lucas, Baja California Sur, August 2020. Length: 16 cm (6.2 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).

The Barred Flagtail, Kuhlia mugil, is a member of the Flagtail or Kuhliidae Family, that is also known as the Five-bar Flagtail and the Ocean Flagfish and in Mexico as dara bandera. Globally there are twelve species in the genus Kuhlia with this being the only found Mexican waters, and it in the Pacific Ocean.

The Barred Flagtail has an elongated oval-shaped compressed body that has a body depth that is 32% to 36% of standard length with a straight upper head profile and a convex lower profile. Their body is silvery with the caudal fin having black and white stripes and white tips. Their tip of the snout and chin has a black tinge. Their second dorsal fin has a dusky band near the margin and terminates with a white tip. Juveniles are similarly marked as the adults with the exception that the middle band of the caudal fin is limited to a black spot near the margin of both lobes. Their head has large eyes and a mouth that is strongly oblique with a projecting lower jaw that is equipped with teeth set in bands on the center and sides of the roof of the mouth. Their gill cover is serrated. Their anal fin has 3 spines and 9 to 11 rays; their caudal fin is moderately forked; their dorsal fin has 9 spines and 9 to 11 rays and is deeply notched. They are covered with rough scales.

The Barred Flagtail are found in large aggregations around rocky areas and coral reefs within the surge zone at depths up to 26 m (85 feet). The juveniles can be found in tidal pools and will enter the freshwater mouths of creeks. They reach a maximum of 50 cm (20 inches) in length. They are nocturnal predators that consume zooplankton and small fishes. The Barred Flagtail 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 Barred Flagtail has a wide global distribution is a resident of Mexican waters of the Pacific Ocean but has a very limited distribution being found around the southern tip of Baja California Sur and in the waters adjacent to Clipperton Island and the Revillagigedo Islands.

The Barred Flagtail is a straight forward identification that cannot be easily confused with any other species.

From a conservation perspective the Barred Flagtail is currently considered to be of Least Concern with stable, widely distributed populations. They are of minor commercial interest, being caught with gill nets, seines, and by hook-and-line. They are utilized as a human food being sold fresh or dried salted, as a live bait, and by the aquarium trade including public aquariums.