Migratory birds

The other morning, I spied a yellow-rumped warbler outside the office window. Just a brief moment that turned into a highlight of the day.

Bird watching anyone? It’s easy, doesn’t take much equipment and is cheaper than a lot of other hobbies — ask any boat owner. And it can brighten an early spring day when the weather wants to shackle us to winter.

One day it’s drab outside, the next day there is a colorful bit of fluff and feathers in the front yard that has just accomplished an amazing feat of migration. Some of those birds, weighing just a few ounces, fly thousands of miles from the tropics to the northern boreal forests.

Although other parts of the country south of Montana are already seeing lots of songbirds passing through or setting up house, the beginning of May is a bit early for the peak here.

Many migratory birds, such as orioles and yellow warblers, don’t reach their peak arrival here until mid- to late May.

The early birds, like that tiny yellow-rumped warbler, that are here by late April or the beginning of May, have found a niche in nature that allows them to arrive ahead of the feathered mob, find a spot for a nest, attract a mate and get on with the survival of their species.

Several years ago, May 1 blizzards hit the state and no doubt killed a few of the early migrant species.

The early bird gets the worm, of course. But also, the early bird can muscle in on some prime real estate for nesting, which means a better chance to hatch and raise young, have the young learn to fly, then everyone head south by late summer.

Birds arriving too late are pushed into marginal habitat and are less likely to successfully nest for a variety of reasons — less food, more predators, exposure to the elements. So there’s the gamble — arrive early and with warm weather, or even average temperatures, thrive and prosper, or arrive late, or get hit with a cold wet spring, and lose.

By the way, there are several fascinating Web sites on spring migrants. Try the Cornell Lab of Ornithology and National Audubon Society at http://ebird.org/content/ebird. It lists weekly updates by regions, then species. Start at the Explore Data link.

For a Montana flavor, specifically which bird is seen where, find the American Birding Association Web site at http://birding.aba.org. Then, click on Montana under Western U.S. At that point, bookmark it.

What is perhaps more amazing than when birds arrive is how they do it. How do birds navigate over thousands of miles to find just the right spot for raising young and ensuring the survival of their species?

Migrating birds navigate by using the sun and stars, the earth’s magnetic field and probably mental maps. Although that means a warbler that successfully hatched and flew south last summer has to remember the route and fly it in reverse. It’s not easy. And sometimes birds don’t make it.

That yellow-rumped warbler outside the window the other day may still not be done. The species nests into northern Canada and Alaska. So my friend may have just made a pit stop to pick up an insect or two and head north. It’s a bird’s life.

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