California Needlefish, Strongylura exilis
California Needlefish, Strongylura exilis. Fish caught from within Magdalena Bay, Baja California, May 2017. Length: 54 cm (21 inches).
The California Needlefish, Strongylura exilis, is a member of the Needlefish or Belonidae Family, and known in Mexico as agujón californiano. Globally, there are fourteen species in the genus Strongylura, of which four are found in Mexican waters, three in the Atlantic and one in the Pacific Ocean.
The California Needlefish has a very elongated rounded body with extremely elongated jaws, a relatively short beak, and numerous needle-like teeth. They are blue-green dorsally and transition to silver ventrally. They have a dark blue stripe mid-flank and dark pigmentation at the junction of their cheek and gill cover that extends down to their eyes. Their eyes and fins are yellowish. This countershading provides camouflage to avoid predation. Their fins do not have spines. The front lobe of their anal fin is larger than the dorsal fin and their anal and dorsal fins have low lobes at the rear. Their anal fin has 16 to 19 rays; their caudal fin is slightly concave; their dorsal fin has 13 to 17 rays; and their pectoral fins are small. They do not have gill rakers. Their body is covered with small scales.
The California Needlefish is a coastal pelagic species found in lagoon areas with mangroves, in bays, and in harbors at depths up to 100 m (330 feet). They are known to enter freshwater systems. They reach a maximum of 91 cm (3 feet 0 inches) in length. Adults form small schools and are voracious predators feeding on pelagic crustaceans and small fish. Reproduction is oviparous with females laying large spherical eggs in shallow water habitats which attach themselves to floating vegetation via long filamentous tendrils before being fertilized by males. The larvae are pelagic. The California Needlefish 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 California Needlefish is a resident of all Mexican waters of the Pacific Ocean.
The California Needlefish is easy to recognize and cannot be confused with any other needlefish from the Pacific Ocean.
From a conservation perspective, the California Needlefish are currently considered to be of Least Concern with stable, widely distributed populations. They are not commercially important and are caught by recreational anglers as a by-catch. In some parts of their range they are caught commercially using artificial lights and are marketed fresh. They are considered a poor food fish due to their overabundant bones.