In the warmer Svalbard fjords, carrion removal rates were low (0–51.5 g h −1 mean 14.6 ± 9.0 g h −1, n = 5). Amphipods and ophiuroids quickly reduced the bait to bones (207.6–304.7 g removed per hour (g h −1) mean 290.6 ± 7.3 g h −1, n = 4) in cold Svalbard fjords. In these cold Svalbard fjords, the mean carrion removal rates were almost 20 times higher than mean values noted elsewhere, except in the warm Norwegian fjord Kaldfjorden. However, Svalbard fjords with negative bottom temperatures had the lowest species richness and were dominated by lysianassoid amphipods and ophiuroids. Fjords influenced by relatively warm Atlantic waters, both in Norway and Svalbard, had high scavenger richness. To address this, we compared scavenging fauna in eight fjords with different physical characteristics in Svalbard and northern Norway using time-lapse imagery of scavengers consuming Atlantic herring ( Clupea harengus) bait. Factors including temperature and depth can structure Arctic and Subarctic fjord benthic communities, but the response of scavenging communities to these factors is poorly known. Original article on Live Science.In high latitude coastal regions, benthic scavenger communities are largely composed of invertebrates that play a key role in the cycling of organic matter. Knowing how bodies degrade in the ocean can give rescue divers a sense of what to look for, as well as manage the expectations of family members of those lost at sea, Anderson said.įollow Tanya Lewis on Twitter and Google+. In fact, it's quite normal for ocean scavengers to gnaw off feet, and the running shoes simply make the body parts float, Anderson said. This kind of research helps solve mysteries such as the " floating feet" found wearing running shoes that have washed up along the West Coast in recent years. "Now we have a very good idea of how bodies break down underwater," Anderson said. But when oxygen was low, the larger animals didn't come, and the smaller animals couldn't feed. So as long as the carcass entered the water when oxygen conditions were tolerable, the larger animals would feed, opening the bodies up for smaller critters and the squat lobsters, Anderson said. But the smaller animals' mouths aren't strong enough to break the skin of the pigs. The big scavengers (Dungeness crab and shrimp) need more oxygen to smaller creatures like the squat lobsters. When the researchers dropped the first two pigs into the water, the oxygen levels were about the same, but when scientists dropped the third body in, the levels were lower. The Saanich Inlet is a low-oxygen environment, and has no oxygen during some times of the year, Anderson said. The third body likely took so much longer due to the levels of oxygen in the water, the researchers found. Shrimp, Dungeness crabs and squat lobsters all arrived and started munching on the bodies a shark even came to feed on one of the pig corpses.Scavengers ate the first two bodies down to the bones within a month, but they took months to pick the third one clean. It didn't take long for scavengers to find the pigs. At the end of the study, the scientists collected the bones for further examination. The researchers monitored what happened to the pig bodies using the live VENUS cameras, which they could control from anywhere with an Internet connection, and sensors that could measure oxygen levels, temperature, pressure, salinity and other factors.
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