Friday, July 22, 2011

Plants, animals work to beat the heat

Heat may be delightful for mad dogs and Englishmen but for wildlife anything above the average can disrupt normal routine.

And yet animals typically are well appointed to deal with the heat, just as they are with below seasonal average cold weather, biologists say.

Some animals - such as elephants - radiate heat via their large ears. The same for hares and rabbits, notes the National Wildlife Federation.

Other animals shed heavy hair, or their “winter coats.”

Seeking shelter from the sun and staying hunkered down there until the cool of the evening is a trademark for lizards, sinks and snakes while amphibians and other species go through a process can “estivation,” the reverse of hibernation, the Federation says.

In this process toads and such become dormant, even burrowing into mud.
Whatever the mechanism, wildlife doesn’t moan and complain. Neither can they install all-room air conditioning. For them, it is adapt to the stressors or die.

Even fishes have ways to ajust, moving from locations that are too warm to those that are just right.

“Fish do move to cooler water and try find a place that is more comfortable and with more oxygen,” said Phil Hillman, fish management supervisor for the Ohio Division of Wildlife’s District Three office in Akron.

“Like northern pike at Mosquito, which will sit just above the thermocline and not even eat. That would take too much of their metabolism.”

Meanwhile, terrestrial wildlife are suited to life in the bush, even if that bush is stormed by troops of biting insects and impacted by hot temperatures.

However, in some places the heat and the bugs can be a problem. Moose and deer and other ungulates can suffer from being hammered by an infestation of ticks and other blood-sucking insects.

And in Texas the recent oppressively severe and extended heat has caused many doe deer to abandon their fawns.

Fortunately for Ohio, these situations are rare or nonexistent, biologists say.

“Since deer are crepuscular - a scientific term that means moving mostly at dawn and dusk - they avoid the heat of the day by default,” said Mike Tonkovich, Ph.D., the Wildlife Division’s deer management administrator.

“Deer that are in good health will get through this heat wave just fine. And the accompanying rains should be helping to keep summer foods, including crops, available, which is essential regardless of the weather.”

Much the same applies to smaller critters, even those whose pelts are cherished by trappers for their winter-warming characteristics.

“Most fur bearing species also are nocturnal, so they avoid the heat of the day,” said Suzanne Prange, Ph.D., a Wildlife Division wildlife research biologist involved with fur-bearing animals.

“As for flies, mosquitoes, and ticks, they are something that fur-bearers must deal with every year. Unless an animal is otherwise debilitated from disease, starvation, and the like, they are little impacted by these common pests.”

Heat can impact plants, though. When hit hard by the heat, prairie grasses turn the margins - or edges - of their leaves inward to conserve their moisture.

“That’s much the same as what corn does, and most other plants are adapted to the heat as well,” said Guy Denny, formerly of Willoughby and a retired chief of the Ohio Division of Natural Areas and Preserves.

Among the tree species where heat has all ready reached out and touched are Eastern cottonwoods, Denny said.

“They are actually prairie trees that are exposed to the heat and the wind so this is a mechanism whereby the tree can conserve moisture,” Denny said. “I’ve seen my own cottonwoods begin dropping their leaves.”

- Jeffrey L. Frischkorn

No comments:

Post a Comment