Bluebirds have nested successfully in this nest box twice this year and are now on their third attempt. Such nest boxes offer less protection from the heat than natural cavities in dead trees. Photo by Doug Pifer.
One of my editors suggested I write about how wildlife copes with extended hot, dry weather. My first thought was that wildlife is much better than we are at adapting to such weather extremes. But after reading several articles, I soon discovered how wrong I was. Plants and animals are well adapted to survive short periods of heat and drought. But over the past several years, extended bouts of intense heat are becoming more frequent and more severe. The earth’s climate warms by small increments, but minor temperature changes can bring major results. Trees die at an increasingly rapid rate, and the ever-warming temperatures make summer droughts more deadly.
We see worrisome changes all around us locally. Bees, wasps, butterflies, and other insects normally flock to the ox-eye, bergamot, black-eyed Susan, and purple coneflowers now blooming in our pollinator garden. Yet I see very few red admirals, red spotted purples, and hackberry butterflies — three species that were abundant when we moved here a few years ago. During the hottest part of the summer, voracious catalpa sphinx caterpillars normally appear and nearly strip all the leaves of our catalpa tree. But not a single caterpillar showed up this year.
Bluebirds, purple martins, and other native birds have nested and fledged successfully in our nest boxes and gourds. But with temperatures remaining far above average during the day, these birds have less insulation in these man-made nesting places than they would if they nested in natural tree cavities. In sustained extreme weather these birds face more pressure to keep cool while raising their young. Some people use a garden hose to sprinkle water gently on nest boxes during the heat of the day. I hesitate to do that, for fear it will startle the young birds into jumping the nest prematurely, something they are more likely to do in extremely hot weather.
After nesting season is over, migratory songbirds move south and sustain themselves on abundant insects and ripening fall fruit. They arrive in tropical climes just as summer starts in that part of the world. But in recent years, as the weather here begins to warm earlier each spring, migratory songbirds must adjust the time they head back north. Otherwise, they miss the all-important leafing-out of the trees that sustains tiny caterpillars that emerge by the thousands to eat the unfolding, tender leaves. These caterpillars are the main high-protein snack that songbirds depend on to sustain them during their northbound travels. Ongoing satellite studies of bird migration dates show that birds do seem to be adjusting their departure times.
We can’t single-handedly stop the globe from warming, but here are some small things that can help wildlife to cope with extended hot, dry weather:
- A bird bath in your garden, even a shallow pan of water with a rock in the middle, refreshed daily, helps not only birds but insects, amphibians, and other creatures escape the heat.
- Plant trees or shrubs in groups to create shady areas that mitigate the drying effect of direct sun.
- Plant native flowers, trees and shrubs that are better adapted to the local climate (which now includes winters that are a few degrees warmer on average along with the extended summer heat and dryness).
- Stop using pesticides and herbicides that contaminate natural water sources.
Doug Pifer is an artist, naturalist, and writer. He has a Master’s Degree in Journalism from Penn State and has been an editor and art educator. His illustrations have appeared in various books and magazines and he has been a contributor to The Observer for several years. He lives with his wife and assorted animals on 5.7 acres in a historic farmhouse near Shepherdstown, West Virginia.
By Doug Pifer