March 5, 2014
WELLINGTON, New Zealand — They may look like guts stuffed in cellophane, but five fish hauled up from near-record depths off the coast of New Zealand are providing scientists with new insights into how deep fish can survive.
In a paper published this week in the Proceedings of the National Academy of Sciences, scientists from the U.S., Britain and New Zealand describe catching translucent hadal snailfish at a depth of 7 kilometers (4.3 miles).
By measuring levels of a compound in the fish that helps offset the effects of pressure, the scientists say they’ve concluded that fish likely can’t survive below about 8,200 meters (5.1 miles). That would mean no fish at all live in the deepest one-quarter of the world’s oceans.
The snailfish have little pigmentation due to the lack of light in their environment, hence their translucent appearance.
New Zealand marine ecologist Ashley Rowden, a co-author of the paper, said nobody had caught a snailfish in nearly 60 years and so he wasn’t overly hopeful when they sent down a box-like trap into the Kermadec Trench near New Zealand in late 2011.
He said they used mackerel as bait to attract the small sandhopper-like creatures the snailfish feed upon.
“When it came up, it was just amazing to see. It was ‘Oh my God, we’ve got the fish, and we’ve got more than one,’” Rowden said.