A Crab Swarm at an Ecological Hotspot

Vimeo Link:  https://vimeo.com/263695510

YouTube Link: https://youtu.be/FUF2lc_18qs

Team Members:

Jesús Pineda,  Woods Hole Oceanographic Institution
Brett Kuxhausen, Ocean Media Institute


Hannibal Bank seamount off the coast of Panama is an ecological hotspot—a place where many different species can be found. During a trip to Hannibal in 2015, divers in a human-occupied sub found a cloud of sediment on the seafloor near the bottom of the seamount with hundreds of objects moving around inside. The objects turned out to be red crabs, an abundant species never before seen this far south, but known to be a source of food for larger predators such as tuna and whales. The crabs were in a region of low oxygen, possibly to avoid predators. Using an autonomous underwater vehicle, they took photos of the swarm and found that the crabs were grouping like insects, a behavior rarely seen in the ocean. Their discovery could not have been predicted and demonstrates the importance of human observation in the ocean.

Original Publication: 

Pineda, Jesús, Walter Cho, Victoria Starczak, Annette F. Govindarajan, Héctor M. Guzman, Yogesh Girdhar, Rusty C. Holleman,, James Churchill, Hanumant Singh and David K. Ralston, 2016. A crab swarm at an ecological hotspot: patchiness and population density from AUV observations at a coastal, tropical seamount. PeerJ 2016:

Link to Publication: https://peerj.com/articles/1770/

Support Provided by: Dalio Foundation

By the Numbers

Over 40,000 students in 50 US states, the US Virgin Islands, and 25 countries participated as judges in the 2016 Ocean 180 Video Challenge.