Amphibians in the spring

Among the many harbingers of spring are frogs peeping. On the prairie, the boreal frog sings its loudest now.

Boreal frogs are heard everywhere in the spring and early summer. During their April-June breeding season their loud, short chirp that resembles the slow running of a thumb over the teeth of a comb, seems to come from every prairie pond and water-filled roadside ditch.

Frogs, which need to spend their lives in or near water, seem out of place in the semi-arid Northern Plains. What’s next? Alligators and crocodiles?

As one might expect, there are several toad species found on the prairie — plains spadefoot, Great Plains toad, and Woodhouse’s toad.

When it comes to frogs, however, the boreal frog and the northern leopard frog are also at home — home on the range. That’s because those animals have found their niche to reproduce and thrive in the brief spring wet season, then hang on to survive during summer’s dry heat.

By midsummer, the inch-long boreal frogs disappear underground, beneath vegetation, into water tanks, or even on building foundations, anywhere they can keep their skin moist.

For a great description of the boreal frog, including an audio file of its call, go the Montana Natural Heritage Program Web site at http://fieldguide.mt.gov/speciesDetail.aspx?elcode=AAABC05130.

This frog is not the only amphibian sign of spring. The mid-April snowstorm that dropped several inches of snow on central Montana also brought a tiger salamander sighting on the prairie. It is a bit early for this salamander’s breeding season, but they are moving to breeding ponds.

Tiger salamanders are, perhaps, the weirdest looking creature on the prairie. Its body is typically a crazy quilt of blotched olive or pale yellow markings on a black or dark green background, kind of like a blacklight poster from the ‘60s.

Come summer, tiger salamanders survive by spending daylight hours in borrows, under logs and rocks or in prairie dog burrows. People sometimes find this secretive six- to eight-inch-long amphibian in basements, window wells or stock tanks.

Just wait until a summer downpour when folks not used to this psychedelic looking critter find it on their patio.

Like all of Montana’s amphibians, the tiger salamander goes through a larval stage in water (tadpoles are the larval stage for frogs), but some never complete their transformation.

Instead, they stay in water, become sexually mature and breed while keeping their external gills. These salamanders are called axolotls, water dogs or mud puppies. The latter name, perhaps, because they spend their days in the bottom of ponds — the benthic zone — entering the upper water column at night.

Sometimes a lake in the middle of nowhere will be filled with these animals that are not quite salamanders, not quite fish. Where do you think the Axolotl Lakes in southwestern Montana got their names? Not from a bad hand at Scrabble.

Again, for more information check out the state Natural Heritage Web site at http://fieldguide.mt.gov/speciesDetail.aspx?elcode=AAAAA01142.

The seasons continue to move all around us, sometimes soothing, sometimes bizarre, but always moving.

Bruce Auchly is the Montana Fish, Wildlife and Parks Region 4 information officer.