For thousands of years, some of the world's largest filter-feeding whales, including humpbacks, fin whales and blue whales, have undertaken some of the longest migrations on Earth to travel each year between warm breeding grounds in the tropics and nutrient-rich feeding grounds at the poles.
“Nature has fine-tuned these journeys, guided by memory and environmental cues that tell whales when and where to move,” said Trisha Atwood, an ecologist and associate professor in the College of Agriculture and Natural Resources at Utah State University. But she said climate change is “muddying those signals,” causing marine mammals to veer off course. And they are not alone.
Earlier this year, Atwood joined more than 70 other scientists to discuss the global impacts of climate change on migratory species at a workshop convened by the United Nations Convention on Migratory Species of Wild Animals. The organization monitors and protects more than 1,000 species that cross borders in search of food, mates and favorable conditions to raise their young.
More than 20 percent of these species are critically endangered. This was the first time that the congress had met for such a purpose, and their conclusions were: published this month in a report, were alarming.
“Almost no migratory species have been affected by climate change,” Atwood said in an email to Inside Climate News.
From whales and dolphins to Arctic shorebirds and elephants, rising temperatures, extreme weather and changing ecosystems are affecting migration patterns and changing critical habitats across the planet.
The report says Asian elephants, for example, are being driven to higher ground and closer to human settlements in search of food and water amid increasing drought, leading to more frequent human-elephant conflicts. Shorebirds reach their Arctic breeding grounds despite the insect blooms on which their chicks depend for survival.
Seagrass meadows that feed migrating sea turtles and dugongs are disappearing due to warming waters, cyclones and rising sea levels, according to the report. Today about 30 percent The world's famous seagrass beds have been lost, threatening not only the animals that depend on them, but also people. These vital ecosystems store about 20 percent of the world's ocean carbon and also support fisheries and shoreline protection.
