By Rick LaFrombois
Wausau Daily Herald
March 24, 2005

The freeze-thaw cycle known to raise havoc on roads also has taken a toll on small birds.

More than 100 reports of sick or dead birds have flooded the phone lines in recent weeks at Marge Gibson's Raptor Education Group International in Antigo. Those calls have come from throughout north central Wisconsin, including more than 50 from Marathon County and Wausau.

The deaths, suffered mostly by red polls, likely are being caused by a bacteria, possibly salmonella, which has grown in bird feeders during the recent warm-up. A red poll is a small, red-capped finch.

Some predators, including cats and hawks, also likely have fallen ill after eating the dead or sick birds.

The bacteria is eaten by winter-weary birds that congregate more often around feeders this time of year, which is a recipe for disaster that birders can help avert, say Gibson and the Wisconsin Department of Natural Resources.

Feeders should be cleaned weekly with a mild bleach and water mixture. Seed not eaten within three or four days in spring should be picked up and discarded. And bacteria grows more rapidly in seed that absorbs moisture, so it's best to avoid seeds without shells, such as hulled sunflower seeds. Use only whole seeds in spring, when moisture is prevalent.

Birders should wear vinyl gloves while cleaning feeders and picking up sick or dead birds, cautions Julie Langenberg, wildlife veterinarian with the DNR. It's important to wash hands thoroughly after handling potentially infected birds or seed, because contact with salmonella can cause illness in humans.

Heavy hearts

Some birders were frantic when they reported sightings of sick or dead birds at their feeders, Gibson said.

Bird watching is a serious hobby, especially among retirees, she said.

"They take it very personally when birds at their feeder start dying," Gibson said. "They're not pets, but they're birds that they see on a daily basis. They've become friends over the winter."

Jane Raymond-Wood, a birder from the town of Weston, said she recently found a dead bird, possibly a red poll, near one of her three feeders.

"This one caught my eye because it was still out on the snow," Raymond- Wood said. "Only its tail feathers were flapping ... turns out that was the last movement it made. It died soon after."

Raymond-Wood, a member of the Wausau Bird Club, cleans her feeders often and only puts out as much seed as the birds can eat daily, so she was surprised to find a dead bird near one of her feeders.

"Because they die on your property doesn't mean they got (sick) from your seed," she said.

Raymond-Wood, like many birders, likes to look out her picture window, enjoy the sun and watch the birds.

She, like many other birders, does not like to watch the birds suffer. But bird mortality is high, so she does not get attached to the birds that visit her feeders, she said. "I know some people really do get attached."

Bittersweet fascination

The lure of nature understandably leads birders to erect feeders, which has led to the outbreak of bacteria- caused deaths, Gibson said. But if people did not feed the birds, many might starve.

Feeders are popular because they draw nature to a birder's window. "You don't have to go out and snowshoe through the forest to find them," Gibson said.

Red polls, which are smaller than sparrows and have a red spot on their foreheads, spend their summers in Canada. They migrate south until they find an available food source, such as an abundance of feeders erected by birders.

"They're down here for the winter - it's like Florida for them," Gibson said.

Bacteria is prevalent year-round in feeders, but the birds do not congregate as much around them in summer and fall when food is naturally available. Birds also are healthier then, so fewer get sick and die even when exposed to bacteria.

That's why it's important that people realize they can prevent bacterial outbreaks in winter, Gibson said.

Nature's compromise

More than a dozen people have rushed sick birds to Gibson's wildlife education center for treatment. Staff members use an incubator to quickly warm a sick bird back to near its normal body temperature - between 104 and 108 degrees. They then treat the birds with antibiotics and feed them with tubes.

When bacteria attack a bird's digestive system in the wild, it likely has no more than an hour to live, Gibson said.

Red polls, which weigh very little, have a high metabolism and must eat constantly to maintain their body temperatures. By the time they arrive in Wisconsin from Canada, they typically are already in poor health.

Should a red poll fall ill and not be able to eat, its body's furnace shuts down and it quickly dies.

"Anything in nature that's not 100 percent dies pretty quickly - that's nature's compromise," Gibson said. Larger birds have a longer "mercy window," but still can fall victim to the bacteria, she said.

About 10 of the infected birds brought to Gibson continue to struggle for life, including a rare brown thrasher, an elegant, rust colored bird about 11-inches long with a long, curved beak.

During the freeze-thaw cycles of spring, experts recommend birders: