Waltzing With Walter
When Walter the walrus got separated from his herd off Barrow, Alaska, last summer, the 250-pound calf was airlifted to the Alaska SeaLife Center for help. There, the affectionate and playful calf received rock-star treatment and round-the-clock care. Defenders’ Karla Dutton, who is working with the center to remotely monitor the effect of climate change on walruses, was one of his volunteer caregivers. Read about her encounter and watch a healthy and happy Walter playing in his pool at defenders.org/walterthewalrus.
Drought No More
On the heels of one of the worst droughts in U.S. history, scientists are questioning the future of a critter that crawls—and swims—under the radar in the streams of the Southeast.
© Todd Pierson
Salamanders play an important role in forest ecosystems by gobbling up bugs and regulating nutrients. In turn, they are important food sources for birds and mammals. But to survive, they need to stay cool and moist, and their larvae must stay totally submerged in water while they develop.
But in a five-year study beginning in 2005, including 12 months of conditions where water levels reached a 110-year low, biologists found that larvae disappeared at 30 percent of the sites during the drought year, and that adult salamanders migrated from streambeds to underground refuges at twice the rate of non-drought conditions.
“During the drought, adult salamanders demonstrated a 90 percent survival rate from one month to the next,” says Steven Price, a biologist participating in the Wake Forest University and Davidson College study. “It sounds pretty high, but at this rate, less than 1 percent would survive a four-year drought suggested under certain climate scenarios.”
And salamanders aren’t the only amphibian affected by the whacked-out weather.
Although most of the world’s frogs lay their eggs in water, many tropical frogs do not. Outside of water they are protected from aquatic predators but at increased risk of drying out.
By analyzing long-term rainfall data, Justin Touchon, a post-doctoral fellow at the Smithsonian Tropical Research Institute in Panama, found that rainfall patterns are changing just as climate-change models predict. “Over the past four decades, rainfall has become more sporadic during the wet season,” he says. Heavy rains trigger breeding, but as storms become sporadic, the chance of rain the next day decreases and so does egg survival.
Those, like the pantless treefrog, that can switch between laying eggs in water or on leaves may weather the changes better, says Touchon.
Unfortunately, not all frogs are as flexible.
Keepers of the Kelp
Sea otters often make their daily doings look as if life is just fun and games. But a closer look finds these charismatic creatures actually working to help save the planet from global warming.
Scientists already knew sea otters provide big benefits to ocean ecosystems by dining on sea urchins, which would otherwise overgraze kelp forests—destroying as much as 30 feet a month when left unchecked. But researchers from the University of California-Santa Cruz recently found that kelp left to spread absorbs as much as 12 times the amount of carbon dioxide from the atmosphere than if it were munched up by the voracious urchins. The effect is similar to how terrestrial forests remove carbon from the environment. With a thriving population of sea otters around, the urchins must instead hide in crevices and eat kelp scraps.
Although an enhanced sea otter population won’t solve the problem of higher carbon dioxide in the atmosphere, the scientists argue that the restoration and protection of otters is an example of how animals the world over work in different ways to influence the carbon cycle—and how protecting them might actually help protect us.