Fish
Black Swallower
Chiasmodon niger · also called great swallower
Stretching its stomach around prey several times its own body weight, a black swallower takes one of the most extreme feeding gambles in the animal kingdom, sometimes paying for an oversized meal with its own life.
Overview
The black swallower, Chiasmodon niger, is a small, deep-dwelling predator native to deep ocean habitat across tropical and temperate waters worldwide. Its extraordinarily expandable stomach, disproportionately large jaw, and extreme prey-to-body-size ratio make it one of the most physically remarkable feeding specialists found anywhere in the deep sea.
A gamble that does not always pay off
In an environment where meals are rare and skipping one could mean starvation, the black swallower has evolved to seize opportunity aggressively, even when that means swallowing prey so large it occasionally proves to be its own undoing.
Status
Least Concern, remaining widespread across deep ocean habitat worldwide and not targeted by fisheries.
Black Swallower: common questions
How much bigger than itself can a black swallower eat?
This species is famous for consuming prey that can weigh several times its own body weight, one of the most extreme documented cases of relative prey size among vertebrates, made possible by its highly elastic stomach.
Why does the black swallower sometimes die after eating?
This species occasionally swallows prey so large that it cannot fully digest the meal in time, and the prey's decomposition can produce gases that cause the swallower's own stomach to rupture, sometimes proving fatal.
How does the black swallower fit such large prey in its stomach?
This species has a highly elastic, expandable stomach capable of stretching dramatically beyond its normal size, allowing it to accommodate prey much larger than its own body.
Why does the black swallower take such extreme feeding risks?
This species lives at extreme ocean depths where meals are scarce and encounters with prey are infrequent, making it worthwhile to consume as much as possible whenever the opportunity arises, even at some risk.