A fine layer of snow blanketed the ground Saturday, and temperatures hovered below freezing, but neither Dolly nor Anna seemed to mind.

The two female elephants, like many of the hundreds of animals at the Maryland Zoo in Baltimore, might not be native to cold climates. But they've learned to adapt. And having a thick hide and big body doesn't hurt.

"I always tell people, with animals, it's not so much where you're from as much as what you're acclimated to," said Mike McClure, general curator of the zoo in Druid Hill Park.

While visitors won't be returning until March when the zoo reopens for the year, the 1,500 animals and several dozen caretakers never leave. None of the collection moves out of Baltimore for the winter, though many animals are moved to warmer quarters, holding areas on site.

"For the species that are sensitive to the cold, we have designated areas to be taken to," McClure said. "We monitor the temperatures throughout the fall, and when we see trends below their comfort level, we pull those animals," typically the birds and waterfowl are among the most sensitive.

During the winter months, the staff has to work that much harder to ensure the comfort and safety of zoo inhabitants. McClure, whose 15 years at the zoo include work as animal keeper, elephant keeper and elephant manager, said the staff has a plan for every species, no matter the season. No animals have died this winter because of cold weather.

"We're like the post office - rain, sleet or snow, we're still doing what we do," he said.

In wintry conditions, that can mean chipping away ice in the yards so zebras don't lose their footing. It means keeping aerating "bubblers" going in the duck pond to keep water from freezing. It means making sure the African black-footed penguins can get to their pool by breaking up any ice - and then checking that water doesn't refreeze and trap any of the birds.

Animal keepers monitor the hibernating reptile and amphibian collection every day. They need to keep temperatures from dropping below certain levels, but not raise them to the point of waking up the animals.

Once cold weather hits, elephant trainers begin to go through a more rigorous indoor exercise routine with their charges.

But the elephants also venture outside in the snow. McClure and others shoveled and plowed out the entire elephant yard after the recent December storm deposited 2 feet of snow. Dolly is known to eat and chew on snow, while Anna likes to climb little snow-covered hills, McClure said. Tuffy, the male, tolerates snow, but is usually one of the first to head back indoors.

On Saturday, two trainers worked with Dolly and Anna, giving commands to the elephants to lift their legs, cross their feet, raise their trunks or step up onto a giant tire. The exercises, done daily, help tone the elephants' legs and stomachs. They also build trust that allows trainers and veterinarians to work in close quarters with the elephants. The animals, which spend four to five hours a day working with trainers, earned treats of apple fiber biscuits.

After her session with the trainers, Dolly stretched her trunk over a fence, wrapped it around some leaves and branches on a tree and then dropped them into her mouth.

"It can be enriching for the elephants to be out in the snow," said Kevin Murphy, the zoo's assistant curator. "With their body mass, they don't get cold."

Another animal one might not expect to like the cold is the ostrich. McClure said the warm-weather African bird is hardy.

"They stay out year-round, no matter what the weather conditions," he said.

The chimps, too, are drawn to a frozen landscape and all too happy to leave their heated day room to romp in the snow.

"They all run out and look at their yard, and you can tell they're amazed at the difference," McClure said. "Some play in the snow. When they get cold they can come in."

Yet others are simply in their element in sub-freezing weather: the polar bears, the arctic fox, the snowy owls and the ravens.

In the polar bear exhibit on Saturday, Anoki, the female bear, basked in the cold and blinked in the sun as she stretched out on some hay. Magnet, the male with a propensity for rolling in mulch, lumbered about slowly. He wandered toward the pool, but stopped short of venturing in, choosing instead to rest his head on a rock.

"This weather is good for polar bears," Murphy said. "They can lie there for two days, and they don't get cold."