Pacific Fat Sleeper, Dormitator latifrons
Pacific Fat Sleeper, Dormitator latifrons. Fish caught from coastal waters off Mazatlán, Sinaloa, October 2021. Length: 6.5 cm (2.6 inches). Catch, photograph and identification courtesy of Bart, The Netherlands (worldangler.eu).
Pacific Fat Sleeper, Dormitator latifrons. Fish caught from the San José del Cabo Rió, Baja California Sur, April 2022. Length: 7.4 cm (2.9 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.
Pacific Fat Sleeper, Dormitator latifrons. Fish caught from coastal brackish waters off Mazatlán, Sinaloa, October 2018. Length: 11 cm (4.3 inches). Catch and photograph courtesy of George Brinkman, Guelph, Ontario, Canada.
Pacific Fat Sleeper, Dormitator latifrons. Fish caught from the San José del Cabo Rió, Baja California Sur, April 2022. Length: 11 cm (4.3 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.
Pacific Fat Sleeper, Dormitator latifrons. Fish collected by locals with a cast net at the mouth of the San José River, Baja California Sur, July 2005, during a breach in the barrier caused by Hurricane Hilary. Length: 25 cm (10 inches). The identical species in very non-photogenic red-brown and jet black colorations were also in this collection.
The Pacific Fat Sleeper, Dormitator latifrons, is a member of the Sleeper or Eleotridae Family, and is known in Mexico as puyeki. Globally, there are five species in the genus Dormitator, of which two are found in Mexican waters, one in the Atlantic and one, this species, in the Pacific Ocean.
The Pacific Fat Sleeper has an elongated compressed body with a depth that is 31% to 35% of standard length being widest just before their second dorsal fin. They vary in color from jet black to shiny red-brown to yellow-brown with 7 or 8 oblique bars on their upper sides. They have a dark bar under their eyes and several dark brown stripes on the side of their head behind the eyes that extend to the end of their gill cover. They have a pale line at the base of their anal fin and a dark line at the base of their pectoral fins. Their anal and second dorsal fins have rows of spots. Some fish have a prominent blue “ear spot” behind the upper edge of their gill cover. Their head is flat with small beady eyes, a blunt snout, and a large slightly oblique mouth. Their mouth extends to the eyes and is equipped with slender teeth with straight tips set in bands on the jaws. Their anal fin has 1 spine and 9 or 10 rays; their caudal fin is straight; their first dorsal fin has 7 spines; their second dorsal fin has a short base with 1 spine and 8 or 9 rays; their pectoral fins are relatively short and do not reach the anus; and, their pelvic fins are long and widely separated. They have 83 to 114 gill rakers. They are covered with large scale and do not have a lateral line.
The Pacific Fat Sleeper is a demersal species that is found in both freshwater and marine environments over sandy and muddy substrates, such as estuaries, stagnant ditches, and low current velocity coastal creeks in water depths up to 2 m (6 feet) and in coastal areas with elevations of under 30 m (100 feet). They reach a maximum of 61 cm (2 feet 0 inches) in length and of 1.2 kg (2 lbs 10 oz) in weight. Males are slightly bigger than females. They prefer water temperatures between 25oC (77oF) and 33oC (91oF) and they have the ability to migrate from freshwater to the ocean. They are bottom feeders that will sift through the substrate consuming detritus, plankton, and small fish. They are extremely tolerant of dramatic changes in salinity even up to 50%. They are very hardy and capable of surviving for up to 10 hours out of water due to their ability to absorb oxygen through their broad and highly vascularized forehead. They have a lifespan of up to twelve years. The Pacific Fat Sleeper 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 Pacific Fat Sleeper is found in all coastal lagoons and freshwater systems of Mexico’s Pacific Ocean.
From a conservation perspective the Pacific Fat Sleeper is currently considered to be of Least Concern with stable, widely distributed populations. They are sold commercially and raised via aquaculture. Within some South American cultures they are considered an important food fish. They are attractive for marketing due to their long shelf-life without refrigeration. They are also a component of the aquarium trade on a limited basis.