Finescale Triggerfish

Finescale Triggerfish, Balistes polylepis

 Finescale Triggerfish, Juvenile, Balistes polylepis. Fish collected off the ocean surface with a bait net north of Puerto Los Cabos, Baja California Sur, December 2007. Length: 5.0 cm (2.0 inches). Identification courtesy of H.J. Walker, Jr., Scripps Institution of Oceanography, La Jolla, California.

Finescale Triggerfish, Balistes polylepis. Fish caught from the Devil’s Bend section of Magdalena Bay, Baja California Sur, January 2020. Length: 33 cm (13 inches). Catch, photograph and identification courtesy of Brad Murakami, Surrey, British Columbia, Canada.

Finescale Triggerfish, Balistes polylepis. Fish caught from coastal waters  north of Puerto Los Cabos, Baja California Sur, May 2006. Length: 40 cm (16 inches).

Finescale Triggerfish, Balistes polylepis. Fish caught from coastal waters within Gonzaga Bay, Baja California, June 2015. Length: 40 cm (16 inches). Catch and photograph courtesy of Chris Wheaton, Fullerton, California.

Finescale Triggerfish, Balistes polylepis. Fish caught from coastal waters off Mazatlán, Sinaloa, October 2021. Length: 41 cm (16 inches). Catch, photograph and identification courtesy of Bart, The Netherlands  (worldangler.eu).

Finescale Triggerfish, Balistes polylepis. Fish caught from coastal waters off Puerto Adolfo Lopez Mateos, Baja California Sur, July 2016. Length: 59 cm (23 inches). Catch caught by Jesus Camacho, Puerto Adolfo Lopez Mateos, Baja California Sur.

Finescale Triggerfish, Balistes polylepis. Fish caught from coastal waters off Puerto Adolfo Lopez Mateos, Baja California Sur, July 2016. Length: 60 cm (2 feet 0 inches) by Jimmy Camacho, Puerto Adolfo Lopez Mateos.

Finescale Triggerfish, Balistes polylepis. Underwater photograph taken in Zihuantanejo Bay, Guerrero, July 2019. Photograph courtesy of Maude Jette, Dive Zihuantanejo,   www.Divezihuantanejo.com.

The Finescale Triggerfish, Balistes polylepis, is a member of the Triggerfish or Balistidae Family, that is known in Mexico as cochi. Globally, there are seven members of the Balistes Genus, three of which are found in Mexican waters, two in the Atlantic and one in the Pacific Ocean.

The Finescale Triggerfish has a robust, compressed, and oblong body with a depth that is 57% to 61% of standard length. They are a drab uniform brownish-tan color with hints of blue throughout. Mature adults have bright neon blue markings that “light up” on their head and the edges of their fins when feeding or fighting aggressively. Their head has a rounded profile and a flat beak, modest-sized eyes, a small mouth that opens at the front, and powerful jaws with eight heavy human-like teeth on the upper and lower jaws. Their anal fin and second dorsal fin rays are longer than their rear rays; their caudal fin is doubly concave with prolonged lobes; their dorsal fin has three spines, the first of which can be locked erect, the second being one-half the size of the first, and the third being closer to the second dorsal fin than the first dorsal spine; and their pelvic fins are minute. They are covered with thick leathery skin composed of small and fine scales.

The Finescale Triggerfish inhabit rocky reefs and slopes with borders adjacent to sand. They are found from the surface to depths of up to 520 m (1,700 feet). They reach a maximum of 80 cm (2 feet 7 inches) in length and 7.4  kg (16 lbs) in weight. As of January 1, 2023, the International Game Fish Association world record stood at 7.37 kg (16 lbs 4 oz) with the fish caught in coastal waters off Oahu, Hawaii in February 2013. Although they have a vast range the Finescale Triggerfish 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 Finescale Triggerfish is a resident of all Mexican waters of the Pacific Ocean.

The Finescale Triggerfish is an easy fish to identify and normally cannot be confused with any other species, however juveniles and young adults are very similar to the very rare Blunthead Triggerfish, Pseudobalistes naufragium (dark skinned covered with thin blue lines).  They are also quite similar to the Gray Triggerfish, Balistes capriscus, found only in the Atlantic Ocean.

From a conservation perspective the Finescale Triggerfish is currently considered to be of Least Concern with stable, widely distributed populations. They are heavily pursued by b both commercial and recreational anglers via hook-and-line. They are a strong foe on light tackle; they might even be the strongest fish in the ocean pound for pound. Beware of their truly lethal chomp which can take two weeks to recover from! They are caught off the bottom with tradition bottom rigs on cut bait utilizing ample chum, however stronger than normal small hooks are recommended as they will demolish traditional hooks. They are, however, very elusive and travel in large schools that are continually on the move. They can be caught off the beach at certain times of the year. Very small juveniles can be encountered on the surface far out at sea and collected with a bait net; presumably they approach the Panga seeking shelter. The Finescale Triggerfish are deemed an excellent food fish and are primarily used by locals for ceviche. They can be found on rare occasions in the markets of the greater Los Cabos area.