Cookiecutter Shark

The name "cookiecutter shark" refers to its feeding habit of gouging round plugs, as if cut out with a cookie cutter, out of larger animals. Marks made by cookiecutter sharks have been found on a wide variety of marine mammals and fishes, as well as on submarines, undersea cables, and even human bodies. It also consumes whole smaller prey such as squid. Cookiecutter sharks have adaptations for hovering in the water column and likely rely on stealth and subterfuge to capture more active prey. Its dark collar seems to mimic the silhouette of a small fish, while the rest of its body blends into the downwelling light via its ventral photophores. When a would-be predator approaches the lure, the shark attaches itself using its suctorial lips and specialized pharynx and neatly excises a chunk of flesh using its bandsaw-like set of lower teeth. This species has been known to travel in schools.

It spends the day at a depth of 1–3.7 km, and at night it rises into the upper water column, usually remaining below 85 m, but on rare occasions venturing to the surface.

Virtually every type of medium to large-sized oceanic animal sharing the habitat of the cookiecutter shark is open to attack.

Like other dogfish sharks, this shark is aplacental viviparous, with the developing embryos being sustained by yolk until birth.