When one begins a story, it’s always appropriate to start at the beginning.
Once upon a time, Wisconsin looked different, smelled different, felt different. Depending upon how far back one reaches, this part of the world was covered in mile-deep glaciers, sea, or sawdust. The face of the land has changed dramatically over the years.
That goes for the bird life too.
With the climate changing we are perhaps at the beginning of another story, or perhaps in the middle of its telling. But endings hold fascination. What will become of our birds as the temperatures rise and seasons grow drier? What will happen to the species we know and love? Will they disappear, or will they change?
Perhaps the question should be: has the bird life of Wisconsin ever stopped changing?
Can you imagine a Wisconsin bowed beneath the biotic weight of three billion passenger pigeons? Can you imagine a Wisconsin without starlings, rock pigeons, or house sparrows? There was such a place before the arrival of European settlers. Now those exotics are as native to our state as American robins.
At some point Wisconsin played host to long-billed curlews, many greater prairie chickens and countless western meadowlarks. Trumpeter swans once thrived here, until we hunted them to nothing, and then decided to nurture them back from the dead. Bald eagles, eastern bluebirds, and peregrine falcons were almost gone too, but have recently recovered.
Go back only as far as 100 years and birds like northern cardinal and red-bellied woodpecker were scarce north of the Illinois-Wisconsin state line. House finches, now a common yard bird in Wisconsin, didn’t nest in the state until 1986.
The composition of bird species in Wisconsin is in fact in constant flux, partly due to natural causes and partly to the influences of humans. It’s not an excuse to que sera, sera, but a starting point to understanding. There are changes coming. There are always changes coming.
The Breeding Bird Atlas project offers proof.
This year the Wisconsin Breeding Bird Atlas II powers into its final year, the fifth of surveying the status of bird populations in Wisconsin. In every one of the state’s 72 counties scientists — citizen and professional — are busy in the field inventorying what birds are where, and in what kind of numbers.
As you might guess, some birds are holding steady, some are booming and some are not doing so well. You might find it reassuring that populations of fan favorites like the American robin, black-capped chickadee, American goldfinch and Baltimore oriole are stable.
However, other species, like tree swallow and eastern meadowlark, are down from the last atlas completed in 2000. Bobolink is way down, 26 percent in 19 years. Purple martins too have been decreasing steadily for decades.
And then there are the birds that are thriving.
It’s hard to tell from a walk through the woods, but the number of red-eyed vireos is up. So is the population of rose-breasted grosbeaks. American redstarts are really doing well, as are pileated woodpeckers.
One of the biggest winners in the state? The poster bird for the Chippewa Valley — the tufted titmouse.
Titmice have always been an anomaly; a bird common to the American southeast, but tough to find in Wisconsin, except for here in the Chippewa Valley, where the species has established a stronghold.
However, that has changed dramatically, as the population has filled in the gaps between Illinois and Eau Claire and expanded elsewhere in the state.
Is the expansion of the titmouse due to human-made changes to the atmosphere?
“Climate change is likely a factor,” said Ryan Brady, ornithologist with the Wisconsin Department of Natural Resources. “In some cases perhaps one of several factors, but I believe more data would be needed to unequivocally state it’s the sole or even primary factor.”
Wisconsin is taking on a more distinctly southern flavor as birds like wild turkeys and orchard orioles increase across the state. In 2016, for the first time ever, Mississippi kites — a bird that is much more common in Kansas or Tennessee or Texas — were recorded breeding here. Rare barn owls have turned up in higher numbers too and could be breeding here.
“Carolina wrens are a good example of milder winters allowing increased survival and range expansion,” Brady said. “On the other hand, milder falls and winters are likely the cause of decline in Canada jays across the north woods, causing their food caches to rot and leading to lower reproductive success.”
Wisconsin’s go-to-tanager has always been the scarlet, but the summer tanager is prevalent throughout the southern U.S.
“I’m surprised we haven’t yet found a breeding summer tanager yet, but sightings are surely more frequent than in Atlas 1,” added Brady.
And more variable weather conditions have an effect on birds, driving western birds east on strong winds. Wisconsin’s first-ever Hammond’s flycatcher is currently trying to outlast January 2019. Hurricanes bring oddities into the state too, all the way from the Gulf Coast. Not one, but two swallow-tailed kites drifted north to Wisconsin last year.
Brady can’t predict surprise birds, but he can smell change in the air.
“I guess I wouldn’t expect a direct increase in vagrancy, but changing weather patterns could alter patterns ... such as the species involved, their length of stay, survival.”
Scientific projections suggest the climate change could have dramatic effects on our birds — even squeezing certain species into extirpation. Will our orioles and eagles and wrens one day be replaced by ash-throated flycatchers, great-tailed grackles, and Mississippi kites?
That’d just be guessing. Only change is certain.
Betchkal is a bird expert and a freelance writer who lives in Eau Claire.