Pacific Silverstripe Halfbeak, Hyporhamphus naos
Pacific Silverstripe Halfbeak, Hyporhamphus naos. Fish caught from the shore at Los Barriles, Baja California Sur, January 2018. Length: 19.8 cm (7.8 inches). Catch and photograph courtesy of Brad Murakami, Surrey, British Columbia, Canada.
Pacific Silverstripe Halfbeak, Hyporhamphus naos. Fish caught off the Las Barriles Fishing Pier, Baja California Sur, July 2021. Length: 23 cm (9.1 inches).
Pacific Silverstripe Halfbeak, Hyporhamphus naos. Fish caught within the Old Harbor, Puerto Peñasco, Sonora, November 2020. Length: 24 cm (9.4 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.
The Pacific Silverstripe Halfbeak, Hyporhamphus naos, is a member of the Halfbeak or Hemiramphidae Family, that is also known as the Naos Halfbeak and in Mexico as pajarito blanco del Pacifico. Globally, there are thirty-six species in the genus Hyporhamphus, of which six are found in Mexican waters, three in the Atlantic and three in the Pacific Ocean.
The Pacific Silverstripe Halfbeak has and elongated cylindrical slender body. They have a silvery appearance with a translucent back, a silver stripe along their flank with a dark border that widens toward the rear, and a white belly. Their snout and beak are black with a red tip. The fins are transparent to dusky. Their lower jaw extends into a prolonged beak and their upper jaw is short and triangular. They have no teeth. Their anal fin has 15 to 17 rays and originates directly under the dorsal fin; their caudal fin is moderately forked with the lower lobe being larger than the upper lobe; their dorsal fin has 14 to 16 rays and originates behind the anus; their pectoral fins are short, high on the sides, and do not reach the nostrils when folded forward; and, their pelvic fins are on the abdomen well back on the body with the origin being about equal distance between the pupil and the caudal fin base. Their anal and dorsal fins are well back on the body with bases opposite each other. They have 29 to 39 gill rakers. They are covered with large scales. Their lateral line is low on the body.
The Pacific Silverstripe Halfbeak is a pelagic species normally found in coastal waters on the surface to depths of 30 m (100 feet). They reach a maximum of 21 cm (8.3 inches) in length. They feed on small fish and plankton. In turn they are preyed upon by birds, dolphins, dorado, marlins, porpoises, squids, and tuna. Reproduction is oviparous with females releasing large eggs containing a sticky substance that allows the eggs to attach to floating debris. Although fairly common, the Pacific Silverstripe Halfbeak 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 Silverstripe Halfbeak is a resident of Mexican waters of the Pacific but has a limited range being found from Guerrero Negro, Baja California, southward along the central and southwest coasts of Baja, in the southern half of the Sea of Cortez, and along the coast of the mainland south to Guatemala.
The Pacific Silverstripe Halfbeak can be easily confused with the California Halfbeak, Hyporhamphus rosae (lower bill dark red), the Choelo Halfbeak, Hyporhamphus gilli (37 to 50 gill rakers), and the Longfin Halfbeak, Hemiramphus saltator (25 to 32 gill rakers).
From a conservation perspective the Pacific Silverstripe Halfbeak is currently considered to be of Least Concern with stable, widely distributed populations. They are uncommon and of limited interest to most.