A mile and a half (two and a half kilometers) underwater, this alien-like, long-armed, and--strangest of all--"elbowed" Magnapinna squid is seen in a still from a video clip recently obtained by National Geographic News.
In a brief video from the dive recently obtained by National Geographic News, one of the rarely seen squid loiters above the seafloor in the Gulf of Mexico on November 11, 2007.
The clip-from a Shell oil company ROV (remotely operated vehicle)-arrived after a long, circuitous trip through oil-industry in-boxes and other email accounts.
"Perdido ROV Visitor, What Is It?" the email's subject line read-Perdido being the name of a Shell-owned drilling site. Located about 200 miles (320 kilometers) off Houston, Texas (Gulf of Mexico map), Perdido is one of the world's deepest oil and gas developments.
The video clip shows the screen of the ROV's guidance monitor framed with pulsing inputs of time and positioning data.
In a few seconds of jerky camerawork, the squid appears with its huge fins waving like elephant ears and its remarkable arms and tentacles trailing from elbow-like appendages.
Despite the squid's apparent unflappability on camera, Magnapinna, or "big fin," squid remain largely a mystery to science.
ROVs have filmed Magnapinna squid a dozen or so times in the Gulf and the Pacific, Atlantic, and Indian Oceans.
The recent video marks the first sighting of a Magnapinna at an oil development, though experts don't think the squid's presence there has any special scientific significance.
But the video is evidence of how, as oil- and gas-industry ROVs dive deeper and stay down longer, they are yielding valuable footage of deep-sea animals.
Some marine biologists have even formed formal partnerships with oil companies, allowing scientists to share camera time on the corporate ROVs-though critics worry about possible conflicts of interest.
Based on analysis of videos not unlike the one captured at the Perdido site, scientists know that the adult Magnapinna observed to date range from 5 to 23 feet (1.5 to 7 meters) long, Vecchione said. By contrast, the largest known giant squid measured about 16 meters (52 feet) long.
And whereas giant squid and other cephalopods have eight short arms and two long tentacles, Magnapinna has ten indistinguishable appendages that all appear to be the same length.
"The most peculiar structure is that of the arms," said deep-sea biologist Bruce Robison of the Monterey Bay Aquarium Research Institute in California.
Referring to the way the tentacles hang down from elbow-like kinks, Robison said: "Judging from that structure, we think the animal feeds by dragging its arms and the ends of its tentacles along the seafloor as it drifts slowly above it."
The elbow-like angles allow the tentacles to spread out, perhaps preventing them from getting tangled.
"Imagine spreading the fingers of a hand and dragging the fingertips along the top of a table to grab bits of food," he added.
21 окт 2024
