

February 26, 2010\u2014After dropping dead pigs into the sea and watching via Webcams, researchers were \"very surprised\" to see marine scavengers risk low\u2013oxygen waters for a meal.

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Sometimes a scientific study reveals things that were never expected to be part of the discovery.

While conducting forensic studies on human decomposition, scientists in Canada found deep sea dwelling animals taking a chance and going after a pig carcass where oxygen is at extremely low levels.

Pigs are used in decomposition studies because they are anatomically similar to humans.



It\u2019s at depths like this that oxygen drops to very low levels, leading to the term \u201cdead zones\u201d. In recent years, dead zones are occurring more frequently in many areas of the oceans.


In this video recorded in British Columbia\u2019s Saanich Inlet, the first animal on the scene was a squat lobster. Over several days, scientists observed more squat lobsters coming for a meal, as well as crabs and shrimp. This pig carcass was devoured by the 23rd day.

According to Dr. Tunnicliffe, the pigs used in this study, coordinated with Canada\u2019s VENUS project, were originally raised for market. They were euthanized humanely under strict government regulations.

The findings were presented at a meeting of the American Geophysical Union in Portland, Oregon this week.

The scavenger animals usually hang out at shallower depths, where oxygen levels are higher. But the pig carcasses attracted a daring crowd.

If the crabs, squat lobsters and other animals stay too long in oxygen-depleted waters, they will suffocate.

One pig in the experiment sat untouched for nearly 2 months, apparently because the oxygen level was too low to support the hungry scavengers.

The findings will help scientists in their study of other locations, such as the Mississippi Delta, where fertilizer in upstream agricultural runoff lowers oxygen levels.

The so-called dead zones also diminish the success of fishermen\u2019s attempts at catching shrimp, crab and other commercial species.

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