“This organism is surprising,” said Dr. Humberto González, PhD in Oceanography.
Ariel Diéguez, Las Últimas Noticias. “We found small schools of red lobsters that have been seen by almost everyone who passes through these seas. [These lobsters] are far from coloring the sea red, as noted by Dampier and Cowley, which leads me to believe that we never saw more than a few hundred of them at one time. However, we caught several on poles and in nets, and we called them Cancer gregarius.”
In his journal, Joseph Banks, an English explorer and naturalist, recorded observations of clusters of these crustaceans near Tierra del Fuego. His sightings were made from the Endeavor, Captain James Cook’s boat, in January 1769. However, the patches were never enough to cover large expanses of water.
A scientific expedition carried out by the Research Center Dynamics for High Latitude Marine Ecosystems (IDEAL) found surprising densities of the red lobsters now known as Munida gregaria in the area. Perhaps they hid from Banks!
“We turned on spotlights on the boat at night, and the sea practically looked red,” said Dr. Ricardo Giesecke, PhD in Oceanography at the Universidad de Concepción, professor of the Universidad Austral de Chile, and head of this expedition. Like moths to a flame, these little lobsters are drawn to the lights of boats. Thus, these sightings could not be used for calculating population density.
A more precise method was carried out by day. “We hauled in plankton nets, and 95 to 98 percent of what we caught [in them] was Munida. The rest were other organisms. Not only were there many [Munida], they were also large,” said Giesecke. “I had never seen anything like it with a single species.”
Munida gregaria, also known as channel squat lobster, can measure up to six centimeters and has crab-like pincers.
“From an ecological perspective, it has been really interesting. We think this species could play an ecological role similar to krill in Antarctica,” said Dr. Humberto González, PhD in Oceanography at the University of Bremen, Germany; professor at the Universidad Austral de Chile; and director of the IDEAL Center.
Krill is the basic food staple for animals on the white continent, just as Munida gregaria is for whales, sea lions, and even birds in Chile’s XI and XII regions. High concentrations of this species are good news, indicating that no animal that feeds on it will go hungry.
The red lobster is itself a voracious feeder, consuming small organisms and organic matter suspended in the water. “It grabs its prey with the pincers and takes it to its mouth. We had many Munida in containers, and we saw how suddenly a large one grabbed a small one and practically tore it apart. It ripped the smaller one in two, took it to its mouth, and ate the whole thing: pincers, legs, all of it. There is a lot of cannibalism,” said González. “This organism is surprising, very interesting. And it will bring more surprises.”
Smaller organisms that cannot be caught in Munida‘s pincers can be trapped in the small hairs found in several places on this crustacean’s body.
Next year, scientists will have much more precise calculations of the Munida population in the area, thanks to data collected from the instruments installed in Yendegaia Bay and in Pía Fjord. These instruments include sonar devices that can measure shoal sizes.