Noise Follows Heat as Arctic Wildlife’s Woes Mount
Climate change has caused the Arctic to warm at about twice the rate of the rest of the world, and while reduced levels of sea ice leave smaller habitats for animals such as walruses and polar bears, the open waters make those below the surface increasingly vulnerable to noise pollution.
“The melting ice opens everything up for more shipping, more oil, and gas exploration,” Lindy Weilgart, a bioacoustics researcher at Dalhousie University in Halifax, Nova Scotia, told the single-issue news site Arctic Deeply. “At the same time, because of climate change, the storms are getting worse, and so you’ve got more wind and wave noise.”
Noise pollution has long been identified as harmful to marine life. The nonprofit Ocean Conservation Research likens the noise pollution to putting a bucket over animals’ heads: The man-made sounds make it difficult for marine animals to hear the natural ones and communicate with one another to find food and to reproduce. A study published earlier this month found that noise from container ships and oil tankers made it difficult for orcas in the Pacific Northwest to find the salmon they rely on. Communication between endangered North Atlantic right whales has been reduced by as much as 65 percent owing to noise pollution.
The cacophony in the Arctic is compounded by climate change and likely to grow louder. Arctic air temperatures were up an average of 6 degrees Celsius in January, and sea ice extent is the lowest on record for the month, according to the National Snow and Ice Data Center. “We’re at a record low for this time of year right now,” Mark Serreze, the center’s director, told The Washington Post. That’s not a promising start for 2016 as winter turns to spring and what relatively little ice there is will start to melt. Serreze warns, “We are starting out in a deep hole.”
Experts attribute the unseasonably warm January to accelerated warming in the Arctic as a result of greenhouse gas emissions and a strong El Niño event.
Not only did the sea ice keep out much of the shipping traffic, but it helped dampen sound from permeating the ocean surface. Sound travels faster in warm temperatures but farther in cold ones. So even though the Arctic is less cold than in previous years, its low temperatures still allow marine life to hear sound originating from hundreds of kilometers away, Arctic Deeply explains.
A study published in June found that noise from air guns used for oil exploration prevented bowhead whales from communicating with one another in the Beaufort Sea. Researchers note that the whales’ behavior changed even with relatively low-volume sounds.
With oil prices on the decline, oil exploration projects and the noise they generate are on hold—for now. But as sea ice continues to recede as the weather warms, the Arctic is increasingly open for ship traffic. Wildlife advocates are campaigning for quiet sanctuaries for marine life and working with shipping companies to reduce engine noise.