While writing an upland-bird-hunting book in the 1980s, I mentioned a general rule: Birds with high chick survival laid fewer eggs than species with high mortality, and woodcock and ruffed grouse offered good examples. Woodcock with high brood survival lay four to five eggs each spring, mostly four. Grouse with high mortality produce 12 or 13 eggs to perpetuate the species after myriad chick losses to weather and predators.
I had never read this theory of egg numbers vs. brood survival, but it struck me as common sense – albeit as I have often claimed, “common sense” is occasionally a synonym for “collective ignorance.” However, in this egg-number and survival-rate equation, the theory struck me as an example of common sense that works.
When my book editor came across the woodcock-grouse example, he asked me to find a scientific study to corroborate the claim. Normally, the request would have been fine, but in those years before the Internet, I could find no research to substantiate my theory and soon lost interest in looking. After all, would I need a study to corroborate the sun rises in the east or dew-soaked mornings usually turn into fair days?
My egg-number theory struck me as sound, so I refused to keep poring through libraries and calling wildlife biologists, trying to nail down a study. After all, if grouse had high survival with a dozen chicks in each brood, these birds would soon overpopulate their habitat. If woodcock had lousy survival numbers, they’d be extinct with their four-egg strategy.
Here’s another salient point about brood size. A growing human population with increasing pollution and development can upset nature’s egg-laying scheme. A common loon lays one or two eggs and offspring can live up to 24 years, so before humans interfered with loon-breeding habitat, this bird typically enjoyed high chick survival.
However, pollution and increasing development in breeding grounds have made brood survival iffy, and human tampering has occurred so quickly that evolution of the species hasn’t caught up to the new reality.
Just in my adult life, this bird would be in serious trouble without the renewed interest in loon protection.
In Maine, human crowding reduces key breeding habitat for shorebirds that breed on sand beaches – a problem. The state has never had an abundance of this habitat, so any reduction proves critical. Unfortunately, beaches are high-priority real estate for 21st-century humans.
An insignificant pollution incident once made an impression on me that stuck for life: On a late May morning when I was 14 years old, I was hitchhiking to baseball practice past wind-rippled fields on Route 105 east of Hussey’s General Store in Windsor. This quintessential spring day in all its glories included sparkling landscape, deep-blue sky and fresh-smelling air.
A pickup approached going my way, but the driver ignored my thumb and roared past. Much to my surprise, I could smell cigarette smoke coming from the vehicle, so in short, a tiny, tiny smoke plume on such a bluebird day emitted enough gas for my nose to detect. (These days, while bicycling, I occasionally smell cigarette smoke from passing vehicles.)
This single cigarette was a miniscule pollution source, but it made me think of a huge, black smokestack at the old Hudson Pulp and Paper on the Kennebec River in Augusta, belching thick, black, acrid smoke.
If I could smell a tiny cigarette from a passing truck in spring, just think what toxins that paper-mill smokestack was doing to Maine air, animals and plants.
Myriad examples of human-made degradation to the planet catch the attention of astute observers. For instance, smokestacks at coal-fired electric plants in the Midwest reach Maine on west winds and have caused mercury pollution in our freshwater fish. The presence of the toxin has caused Maine’s health department to issue fish-consumption advisories that include northern Maine’s remote trout ponds. There are additional consumption warnings on other individual Maine waters because of PCBs, dioxins and DDT.
This winter, it has been easy to laugh at the prospect of a warming planet, but the severe winter has caused but a statistical hiccup in recent climate change records. Signs are everywhere that the planet is heating up. Some meteorologists claim that we can expect more bad winters, which reminds me of the great ice storm of 1998.
Back then, Maine meteorologists predicted more similar ice storms in subsequent years, which didn’t happen.
Twenty-five years ago, I distinctly remember right-wing advocates claiming that humans were not the cause of global warming. Then, in the last quarter century, their strategy changed from humans are not the cause to there is no global warming. Period.
Talk about diving down the rabbit hole.
Ken Allen, of Belgrade Lakes, a writer, editor and photographer, may be reached at
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