Blackwing Flyingfish

The Blackwing Flyingfish (Hirundichthys rondeletii) is a widely distributed flyingfish in the family Exocoetidae, named for the dark, dusky-black coloration of its large pectoral wing fins. It belongs to the genus Hirundichthys, a group of four-wing flyingfishes that use both enlarged pectoral and pelvic fins to glide above the water's surface. Unusually among flyingfishes, it tolerates cooler waters and is found across a broad temperate-to-tropical range in the Atlantic, Indian, and Pacific Oceans. It serves as an important prey species for tunas, billfish, and seabirds throughout its extensive range. The species is not considered threatened.

Key features of the Blackwing Flyingfish:

• Stout, streamlined body, typically 25-30 cm long
• Dark blue-black back fading to bright silvery sides and belly
• Large, distinctly dusky to blackish pectoral fins, the source of its common name
• Smaller but still enlarged pelvic fins forming a second wing pair
• Short, rounded snout and deeply forked tail with an elongated lower lobe

The dark, largely unmarked black pectoral fins (rather than clear, banded, or mottled wings) distinguish this species from many other Cheilopogon and Hirundichthys relatives. Its tolerance for cooler, temperate waters also sets it apart ecologically from more strictly tropical flyingfish species.

Blackwing Flyingfish live at the surface of open ocean waters, ranging more broadly into cooler temperate seas than most other flyingfish species, in addition to tropical waters. They are found across the Atlantic, Indian, and Pacific Oceans, generally favoring surface temperatures from roughly 15 to 25°C. As an epipelagic species, they remain in the uppermost layer of open water, typically well offshore over deep water rather than near coastlines. Their unusually wide temperature tolerance allows them to occur further from the equator than many related species.

Like other flyingfish, the Blackwing Flyingfish escapes predators by accelerating underwater, breaking the surface, and spreading its large pectoral and pelvic fins to glide, often using rapid tail beats against the water to extend or redirect its flight path. It typically occurs in loose aggregations near the surface and feeds on small planktonic organisms. As a widely distributed forage species, it is an important prey item for tunas, billfish, dolphinfish, and seabirds across a broad range of ocean temperatures. Spawning occurs at the surface, with eggs bearing adhesive filaments that attach to floating algae or debris until hatching.