How do anhingas catch fish underwater?

Anhingas, also known as snakebirds, are highly adapted for underwater swimming and employ a distinct hunting strategy compared to other pelecaniforms. Unlike cormorants, which actively pursue free-swimming or bottom-living fish, anhingas do not chase their prey. Instead, they lie in wait underwater and stab passing fish with their bills. They primarily feed on slow-swimming, laterally flattened fish.1

Their ability to remain submerged is facilitated by their physical characteristics. Anhingas have wettable plumage that traps very little air, which keeps their buoyancy low and allows them to submerge directly from the surface without needing an aerial dive. Additionally, they have less pneumatized bones than other pelecaniforms, giving them a higher specific gravity that helps them remain underwater while motionless. Anhingas are capable of staying submerged for significant periods, often for as long as two minutes, with some recorded dives lasting nearly seven minutes.21