Imagine a planet where jellyfish rule the seas, giant rodents roam the mountains and swarms of insects blur everything in sight. It may sound far-fetched, but enough global warming is likely to change the distribution of wildlife on Earth. While species that are under threat, such as the polar bear, seem to get all the attention, others are beginning to thrive like never before.
In the past three months, new studies have been published about killer whales, wandering albatross and trumpeter swans—all of which appear to be benefiting from climate change.
Melting ice is turning the Arctic Sea into a giant buffet for killer whales. They have been arriving in growing numbers to feed on belugas, seals and narwhals, according to a recent study by scientists from the University of Manitoba. Warmer temperatures make it easier for the whales to hunt because their prey is less likely to climb onto sea ice or hide below it to escape.
At the opposite end of the world, in Antarctica's Southern Ocean, changing winds have been helping the wandering albatross find food faster. Researchers say global warming has produced stronger air currents that allow the birds to spend less time away from their nests, increasing the odds that their chicks will survive.
"The duration of foraging trips has decreased, breeding success has improved and birds have increased in mass by more than 1 kilogram," wrote the study's authors, who called their findings "positive consequences of climate change."
In Arctic areas, global warming is happening at roughly twice the average speed, which has allowed Alaska's trumpeter swans to expand their breeding grounds northward into regions that were previously too cold, according to a study published in Wildlife Biology in December.
....White-tailed deer in the northern United States are already showing a population boom thanks to this year's lack of snowfall, which has made it easier for the animals to find food, said Curtis. He also believes a warmer spring could benefit snakes and salamanders, giving them more time to grow and add to their fat reserves.
...Jellyfish populations are also suspected to be swelling because of climate change. In recent years, the creatures have been clogging the nets of fishermen, stinging record numbers of beachgoers and blocking the water intake lines of power plants in at least three countries. Some scientists are linking the phenomenon to warmer waters and ocean acidification caused by high levels of carbon dioxide in the atmosphere. Studies have found that today's oceans are 30 percent more acidic than in the 18th century, when the Industrial Revolution began.
...Certain species of insects, like mosquitoes, ticks and invasive beetles, are also expected to benefit from warmer temperatures. In fact, a 2003 study published by the Ecological Society of America concluded that "all aspects of insect outbreak behavior will intensify as the climate warms."
...Future levels of carbon dioxide may help beetles, as well, according to researchers from the University of Illinois, Urbana-Champaign, who found that Japanese beetles lived longer and laid more eggs after eating leaves that were grown in an environment with additional carbon dioxide.
..."What we really don't know is what the long-term consequences of climate change are," explained Curtis. "There will definitely be winners and losers, and it's hard to predict what some of those will be." He said animals that can migrate—like whales and birds—are more likely to adapt, while species bound to a particular environment, or food source, will face greater challenges.
Even creatures that appear to be benefiting today may not be so lucky in the future. Scientists predict the winds that are helping the wandering albatross will become increasingly violent by the end of the century, threatening the birds' survival. And Colorado's marmots don't easily adapt to heat, so rising temperatures may soon put them—and the plants they eat—at risk.
"It's hard to say if swans will even benefit long-term," said Schmidt, who explained that the ponds they live in may already be drying up. "If those sorts of things are occurring, it might be a zero-sum game. Or it might be negative."
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