NORTH AMERICA IS HOME TO UNUSUAL ANIMALS

by Whit Gibbons

March 14, 2004

Because most TV nature shows still focus on exotic fauna to the exclusion of homegrown varieties, some columns are worth repeating. I am not suggesting that koalas from Australia and anacondas from South America be banned from the airwaves. To be sure, these are fascinating animals worthy of recognition. What concerns me is that many viewers get the impression you must go to exotic lands to see engaging creatures.

Some people think that North America has little to offer in the way of intriguing mammalian wildlife aside perhaps from wolves and grizzly bears. But we actually have several species of notable mammals that most people have never seen or heard of. Even biologists know little about some of these creatures, so they are seldom if ever the topic of discussion.

Three such specimens that come to mind are the mountain beaver and the pika of the West and the starnose mole of the East. Ironically, all may owe their continued existence to having virtually no economic significance; they are neither something good to acquire or bad to get rid of.

Everyone is familiar with the dam-building beaver, our largest rodent. But what do we know about the mountain beaver, or aplodontia, of the western states? Mountain beavers are also rodents but belong to a different family from true beavers, and the North American species is the only living member. They are considered to be the most primitive rodents in the world.

Mountain beavers, which have no obvious tail, look somewhat like dark brown guinea pigs a little more than a foot in length. They have tiny ears and eyes. Little is known of their biology except that they live along the edges of waterways where they make burrows and trails. A certain type of flea is found only on mountain beavers and would have no interest in biting a dog or human.

The starnose mole of the eastern states is an enigma, its most intriguing feature being 22 long, fleshy tentacles that flare out from the end of the nose. The exact function of the tentacles remains unknown, as far as I am aware, but the tentacles may be used to find prey by sensing vibrations. Starnose moles differ from the half-dozen kinds of soil-digging moles of North America in being expert swimmers. They reach lengths of less than six inches, are generally found near streams or lakes, and are seldom obvious.

The general ecology of the starnose mole is poorly understood, and many biological mysteries surround these creatures. Even the geographic range of starnose moles is open to question and may be much greater than shown in mammal field guides. Researchers at the Savannah River Ecology Lab have captured them in areas where they have not been previously reported. These have been captured with a trapping system known as pitfall traps designed to capture reptiles and amphibians. Starnose moles fall into the pitfall traps, but they do not enter standard mammal traps and so may go undetected by mammalogists.

Pikas are closely related to rabbits. These little balls of brown or gray fur are restricted to high mountain regions where they live among the rocks. They have big rounded ears and no tail, and they make squeaking sounds like a squeeze toy. They eat mountain vegetation, storing grasses beneath boulders for a food supply during cold periods. The most likely place to see a live pika is in western mountains. I have seen them peeking out from craggy slopes in Rocky Mountain National Park.

And if other unusual North American creatures are needed for the nature show, how about flying squirrels, which are found in most of the states and all Canadian provinces but are seldom seen because they do their aerial gliding at night? And what about the two-inch-long pygmy shrew of Canada and colder parts of the United States, a tiny animal that is possibly the world's smallest mammal?

Nature shows could reduce travel budgets by focusing on interesting U.S species. A show on lightning bugs, velvet ants, chicken turtles, or glass lizards could be captivating. No need to go far afield for a glimpse of exotic animals: we have our share of biological mystery and intrigue at home.



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