Researchers often use some tried and true methods for collecting animals from the ocean. In addition to nets, fairly standard traps are used to catch many different organisms from small zooplankton and amphipods that live under sea ice to fish and crabs around hydrothermal vents. To attract animals, the traps are baited with a variety of foods, such as rotten fish, cat food, or even the leftovers from the galley of a Research Vessel. After a little bit of time, these traps can then be collected by divers or by submersibles and brought to the surface with the animals alive and in good shape for study. Traps must be specially designed with pressure and/or temperature control if the animals from the deep are to be studied alive after being brought to the surface.

A trap for catching crabs has been placed next to a hydrothermal vent by the submersible ALVIN. (W. Joe Jones, Monterey Bay Aquarium Research Institute, MBARI).

This potentially new giant Antarctic amphipod crustacean – of the genus Eusirus – was one of the stars among the species collected during the trip to the Weddell Sea in 2006–07. Nearly 10 centimeters (4 inches) long, it was sampled by using baited traps off the Antarctic Peninsula. (C. d'Udekem, Royal Belgium Institute for Natural Sciences, 2007)