Spotted Sleeper

Spotted Sleeper, Eleotris picta

Spotted Sleeper, Eleotris picta. Fish collected by locals with a cast net at the mouth of the San José River, Baja California Sur, January 2011, during a breach in the barrier. Length: 18.0 cm (7.1 inches). Identification courtesy of H.J. Walker, Jr. and confirmed by Dr. Phil Hastings, Scripps Institution of Oceanography, La Jolla, California.

Spotted Sleeper, Eleotris picta. Fish collected by locals with a cast net at the mouth of the San José River, Baja California Sur, August 2008, during a breach in the barrier. Length: 54 cm (21 inches). Identification courtesy of H.J. Walker, Jr. and confirmed by Dr. Phil Hastings, Scripps Institution of Oceanography, La Jolla, California.

The Spotted Sleeper, Eleotris picta, is a member of the Sleeper or Eleotridae Family, and is known in Mexico as guavina manchada. Globally, there are thirty-three species in the genus Eleotris, of which three are found in Mexican waters, two in the Atlantic and one in the Pacific Ocean.

The Spotted Sleeper has a stout elongated body with a depth that is 22% to 26% of standard length that is deepest before the first dorsal fin. They are dark brown to blue-gray with a lighter colored belly and numerous white spots covering their body. Their fins are dark with transparent spots producing alternating bands of clear and dark. Their head is broad and depressed with a short snout, small eyes, and a large oblique mouth that has a strongly projecting lower lip equipped with several rows of small conical teeth on both jaws. Their gill openings are well back ending just before the first dorsal fin origin. They have a strong forward pointing spine embedded in the lower rear corner of their gill cover. Their anal fin has 1 spine and 7 or 8 rays; their caudal fin is round with a long base; their first dorsal fin has 5 or 6 spines with a short base; their second dorsal fin has 1 spine and 7 or 8 rays and is shorter than the distance separating it from the caudal fin; and, their pelvic fins have 1 spine and 5 rays and are long and completely separated. They are covered with small rough scales and they do not have a lateral line.

The Spotted Sleeper is found in fresh and brackish waters at depths up to 5 m (15 feet). They reach a maximum of 54 cm (21 inches) in length as established by a fish in my possession, which extended the known length for this species by a full 18.5 cm (7.3 inches). They take refuge during the day in rocks and bushes and emerge at night as carnivorous ambush predators feeding on crustaceans and fish. They are found at elevations up to 90 m (300 feet) preferring low volume stagnant freshwater with year-round temperatures between 25oC (77oF) and 33oC (91oF). They feed on small shrimp and fish. Reproduction includes pelagic eggs and larvae. The Spotted 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 Spotted Sleeper is a resident of Mexico’s freshwater freshwater systems that drain into  the Pacific Ocean but they have a limited distribution being found around the tip of the Baja, Baja California Sur, in the lower half of the Sea of Cortez, and along the coast of the mainland south to Guatemala.

From a conservation perspective the Spotted Sleeper is currently considered to be of Least Concern with stable, widely distributed populations. They are an important food fish in several countries of South America where they are cultivated and exported to the United States. Although fairly common in Mexican freshwater of the Pacific watershed, they are of limited interest to most with the exception of subsistence fishermen.