The soundscape produced by narwhals is giving researchers new insights into their summertime feeding behaviors. It also shows that the whales have a daredevil streak as they swim close to glaciers that are in the process of releasing icebergs.
The catalog of narwhal noises adds to a growing understanding of these enigmatic animals. Scientists recently looked into the advantages for narwhals with big tusks. While most of us will never encounter a narwhal in the wild, we can live vicariously through the scientists' recordings. Biologist Susanna Blackwell and colleagues listened in on the clicks, buzzes and calls of the East Greenland narwhal Monodon monoceros.
The research could help scientists determine how human-made noises may affect narwhals as the Arctic warms due to climate change and shipping lanes become more open. Many whale sounds are recorded using hydrophones, underwater microphones that dangle in the water. Blackwell and colleagues skirted these issues by attaching an acoustic recording device to the narwhals themselves.
With the help of native Greenland hunters, the researchers tagged six of the skittish creatures from to After three to eight days in the water, magnesium links to the string degraded and released the device, which the researchers retrieved using GPS.
Several whales socialize with each other at a depth of 65 meters, using clicks, whistles and trumpet sounds. Tagging was stressful for the narwhals , says Blackwell, who works for Greeneridge Sciences, Inc. But after a day of silence, the narwhals resumed their normal behavior. Like other species of toothed whales, narwhals use echolocation to hunt in the dark arctic waters. The researchers found that the narwhals clicked while diving to locate their prey, often arctic and polar cod or squid.
When closing in on a meal, the clicking sounds turned into a rapid buzzing noise. What they learned could help future studies of whether the whales might be disturbed by human-made noise from fishing or oil drilling, the scientists hope. Narwhals rely on sound in the dark Arctic waters where they live. Like other species of toothed whales, narwhals use echolocation to hunt.
She studies whales and their songs at the University of Washington in Seattle. Whale sounds are often recorded using hydrophones HIGH-druh-fohnz.
These special underwater microphones dangle in the water to collect sounds. But these devices have a few drawbacks. So Blackwell and her colleagues came up with a different solution.
They attached acoustic recording devices to the narwhals themselves. With the help of native Greenland hunters, the researchers tagged six of the skittish creatures between and The devices stuck to the whales with suction cups. Narwhals can be found off the coast of Canada, too.
It makes sense, Podolskiy said, because the fish the narwhals eat can move pretty fast, so the narwhals need to be accurate. Watch the video to hear how the creatures sound underwater New recordings that capture the sound of narwhals buzzing, clicking and whistling underwater could help scientists learn more about the mysterious creatures. What are narwhals?
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