Zoo Animals Adapt to Winter Weather

Jan. 9, 2010 — -- This week when sub-zero temperatures hit the nation, we humans bundled up and made the best of it. But animals can't just reach for some mittens and a muffler, and that's why many species have been having a terrible time tolerating the unusual fluctuations in temperatures.

In Florida, "cold-stunned" sea turtles have been found floating on the water. Thousands of butterflies in Coconut Creek are grounded because they can't flap their wings in weather this cold. Iguanas have been dropping off branches because the cold puts them into a deep sleep. And zoos across the nation are scrambling. In Texas, zookeepers have raced to set up heat lamps and lay out plastic tarps to protect animals like kangaroos that could easily succumb to frostbite.

But at the Franklin Park Zoo in Boston, the animals are better prepared than most to meet the demands of winter's harsh conditions. Christopher, the zoo's "Lion King," spends most of his day basking on a 75 degree heated rock that the zoo had installed especially for him. From there, Christopher can survey his kingdom while remaining toasty warm on even the coldest of days. Zookeepers activate the coils under the rock in late fall and keep it on throughout the winter. There are heated rocks for the two tigers, too.

"People are always surprised that we have lions and tigers out here in the winter. But you have to remember, lions used to roam all the way up into Europe," said John Linehan, executive director of Zoo New England.

And because temperatures in New England regularly drop down to the 20s and 30s in the winter, the animals have been acclimated to the cold. That's an advantage their southern counterparts don't have.

"When it gets below zero it's more challenging for us, but for the most part we have designed the zoo and acquired animals that can adapt to the cold weather," Linehan said.

Warm-Weather Animals Adapt to Boston's Winters

On a recent snowy day in the 20s, the Grant's Zebras, a species that hails from Africa, were shuffling through the snow eating hay.

Chilean flamingoes pranced about quite happily on the ice and snow thanks to a hay bed that gives their tiny feet some traction and protection from the elements. A water churner keeps their critical water supply circulating.

Wildebeests, also from Africa, were snubbing their indoor shelter and roaming a snow-packed field.

Linehan and his staff have paid special attention to the kinds of species that would do well in the winter because the zoo is open year-round.

"We need them to be cold-hardy," Linehan said. And any new animal spends the first year or so with limited time outdoors in winter so they can get used to the colder climate. "It takes about a year until they are better adapted to our environment," he said.

The camels are a good example of a seemingly warm-weather species that is thriving in a cold-weather climate. "The camels we have could live with anything our winter could throw at them," Linehan said.

They are Bactrian camels and they come from Central Asia and the Gobi desert where temperatures can rise to over a 100 degrees and drop down below zero, according to Linehan. In addition, they have developed a 4- to 6-inch-thick winter coat that insulates them from the cold. The hair sheds in sheets in the spring.

Often it's not the snow or cold that's the biggest hazard for zoo animals, it's the ice. In snow, hooved animals can grip the ground quite well, but ice is a different matter and a slip or a fall could be disastrous.

That's one of the reasons why the giraffes here spend most of their time indoors in winter.

"Because giraffes have a lot of surface area relative to body mass, we are pretty conservative when they go out. They can't get down the long pathway to their exhibit when the conditions are icy," Linehan said. And their bodies are simply not equipped to handle the bitter cold.

The temperature cut off for the male, Beau, and his mate, Jana, is around 60 degrees. It's no easy feat to protect a several-thousand-pound animal from the elements. But the Franklin Park Zoo built a special 45-foot-high heated barn with gauges at the top and bottom to constantly monitor the temperature. And there are Christmas trees dotting the enclosure to give the mammoth mammals something to play with during the day.

Zoo Animals Bulk Up for Winter

Zookeepers pay special attention to the food they set out for the animals -- adding special fiber such as beet root in the food to help the animals bulk up for the colder season.

"Our animals look a little more, um, robust than the animals in Southern Africa, in part because they have an extra little layer of fat," Linehan said.

If you love animals and you're thinking of going to a zoo, the cold can actually be an advantage. There are none of the summertime crowds, and the animals actually tend to be a bit peppier.

Christopher, the Franklin Park Zoo's lion, spent a recent morning roaring loudly and often from his perch on the heated rock -- a sound that could be heard all around the relatively empty zoo.

"He doesn't do this quite so often in the summer," Linehan said. "He's really a magnificent animal."