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Marine Animal Encyclopedia

Whiptail Gulper Saccopharynx lavenbergi

The Whiptail Gulper is a deep-sea fish noted for its ability to swallow very large prey, at least as large as its own body size. The oversized jaws and the stomach that is capable of stretching to accommodate large prey allow it to swallow just about anything that swims by. This ability to attack and swallow large prey is one of several adaptations that make the Whiptail Gulper a successful predator in the deep sea.

The Whiptail Gulper lives in very deep waters of the eastern Pacific Ocean from 6500 to 10,000 feet (2000-3000 m) below the sea surface! At that depth, food is scarce, and it is important to never pass up a meal when it becomes available. Some predators have long, needle-like teeth that they use to grasp lively prey, but the Whiptail Gulper uses its ability to swallow large prey whole to ensure that even a big meal is not too much to pass up. Vision is not particularly important for hunting in these depths, where no sunlight can reach. Consequently, the Whiptail Gulper’s eyes are small and rudimentary. The body is long and eel-like, and there is a light organ at the end of the very long tail, which may be used to attract prey or to attract mates.

Like most species in the deep sea, the Whiptail Gulper is very difficult to study and is only known from specimens that are brought up from deep nets. It has never been observed in its natural environment. For that reason, there are gaps in scientists’ knowledge about the behavior of this interesting fish. Unfortunately, it is difficult or impossible to keep this species alive in an aquarium. Based on specimens brought up during deep-sea surveys, scientists hypothesize that adult Whiptail Gulpers, like some salmons and other marine animals, may die after reproducing only one time.

Whiptail Gulpers are not eaten by people, and there is no evidence to suggest that people have any negative affects on their populations. They are likely naturally rare, and only a few specimens are available in fish collections around the world.

Additional Resources

Whiptail Gulperzoom image
  • Distribution eastern Pacific Ocean from California to Peru
  • Ecosystem/Habitat deep sea/open ocean (bathypelagic)
  • Feeding Habits ambush predator
  • Conservation Status unknown but likely stable
  • Taxonomy Order Saccopharyngiformes (swallowers and gulpers), Family Saccopharyngidae (swallowers)
Whiptail Gulper habitat mapzoom image