Distinctly Montana Magazine

w w w. d i s t i n c t ly m o n ta n a . c o m 23 test your knowledge of How wildlife in Montana cope witH winter ground squirrel 3. EvEryonE KnowS Many of Montana'S BIrdS MIgratE South for thE wIntEr, But do BIrdS EvEr hIBErnatE? Yes. One species of bird in the world is known to hibernate, and it breeds in eastern Montana! The common poorwill, a small brown bird related to nighthawks, hibernates for weeks at a time in order to survive cold periods when insects are not active. Common poorwills may also migrate to the southern United States for the winter. 4. thE ClaSSIC "rEEEEK" Call of MalE BorEal ChoruS frogS IS onE of thE fIrSt SIgnS of SPrIng, But what haPPEnS to thEM durIng thE wIntEr? do thEy hIBErnatE lIKE SoME MaMMalS do? Sort of, but not quite. Hibernation in amphibians is called brumation. Unlike mammals, amphibians are ectothermic (cold-blooded) meaning they rely on their environment for heat so the physi- ological processes for overwintering are different. Unlike mammals, boreal chorus frogs and many other amphibians freeze nearly solid in winter, but they suffer no ill effects because of a protective substance called glycerol, a sugar produced by the liver. When the outside temperature warms, boreal chorus frogs are reanimated. 5. In SoME yEarS roBInS arE around all wIntEr, But In othEr yEarS thEy dISaPPEar. what'S thE dEal? arE roBInS MIgratory or not? Yes and no. Robins are irregular migrators. In winter robins form small flocks and become nomadic. If there is enough food where they breed then they'll remain resident, but if food is scarce they will migrate so don't be surprised to see one in your backyard this winter, especially if you have a bird feeder. 6. afrICa IS faMouS for thE 300-500 MIlE MIgratIon of wIldEBEESt In thE SErEngEtI. whICh of thESE Montana MaMMalS MIgratES JuSt aS far? a. Wolverine B. Pronghorn C. Elk d. Wolf If you answered b, you're right. Every year, pronghorn, the fastest land mammal in North America, migrate between 250 and 500 miles from southern Saskatchewan and Alberta to northern Montana. Like other ungulates elk also migrate, but wolves and wolverines do not although they can disperse great distances. 7. wE Know SoME BIrdS lIKE SandhIll CranES MIgratE South for thE wIntEr, But do any BIrdS MIgratE South to Montana for thE wIntEr? a. Snowy owl B. Bohemian waxwing C. Trumpeter swan d. No. Birds from the north skip right over Montana on their way south If you answered a, b, and c, you're right. It's hard to imagine, but all three species migrate to Montana for the winter. Trumpeter swans breeding in Canada spend the winter feeding on submerged vegetation on Montana's ice-free rivers and lakes. Snowy owls and bohemian waxwings breed in the far north, but migrate to Montana and other northern states in December. Some years hun- dreds of snowy owls migrate as far south as Texas in what is known as an irruption. 8. what IS an anadroMouS fISh and arE thErE any In Montana? Anadromous fish are those that migrate from the sea to spawn in freshwater. White sturgeon living in the Kootenai River in northern Montana were historically anadro- mous. Before the little ice age ended 11,000 years ago, white sturgeon migrated from the Pacific into Kootenai River between Troy and Libby, Montana — a journey of more than 700 miles made every spring. But retreating glaciers created an impassable waterfall leav- ing the population stranded. It's the only known naturally occurring inland white sturgeon population in the United States (others were created by dams). The Kootenai River white sturgeon was listed as endangered in 1994. These are just a few of the winter adaptations of Montana's amazing wild- life. As you warm yourself with a hot cup of cocoa this winter, remember the many ways in which wild- life in Montana survive the harshest of seasons. bigHorn sHeep boreal cHorus frog grizzly bear Photos courtesy of Yellowstone National Park

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