Always in Season: House sparrows present a mystery
Dave Lambeth's review of Christmas Bird Count numbers pretty much confirmed that house sparrows are declining in Grand Forks. The number of house sparrows seen on this winter's count was 355, the smallest count since the 1960s, when many fewer people turned out to count winter birds in the city.
Counts in the 9,000 to 10,000 range were reported in the early 1970s. Since then, the number has been going down. In 2010, it fell below 1,000.
This is consistent with numbers from elsewhere, although in some areas house sparrow numbers appear to be stable.
My own experience is that I've been seeing fewer house sparrows. At first, I assumed that was due to my own changing habits rather than a real decline in the number of house sparrows. I spend much less time in the heart of Grand Forks than I used to, and my daily walks are through open country now, rather than in urban neighborhoods.
Later I wondered if changes in Grand Forks itself might explain why I was seeing fewer of these birds. Put plainly, the city is cleaner than it used to be. Grain handling techniques have improved, and less grain is spilled. People don't so casually throw bread crumbs onto city berms. Litter — alas not eliminated — seems to have lessened.
All of this might influence house sparrow numbers. House sparrows are gleaners. They pick food where they find it. Often that means scavenging in places where humans are numerous, because humans are discarders.
The relationship between house sparrows and humans is a close one. The sparrows are probably dependent to some degree on human activity, and not just human waste. The birds nest in crevices in our buildings. I remember finding their densely woven nests in the eaves of the barn on the farm where I grew up.
That suggests still another potential reason for the decline of house sparrows. Building standards are much stricter than they were; it's possible that Grand Forks offers fewer nesting sites than it used to.
Potentially, it also offers fewer nesting materials. On the farm, house sparrows often wove animal hair into their nests. That's not readily available in the age of autos. Long grass, another common nesting material, is also in shorter supply, since we keep things much more closely trimmed than we used to.
The nesting habits of house sparrows suggest their origin. They are not native of North America. Rather than New World sparrows, they are Old World weaver finches.
House sparrows were introduced in New York in 1851. By 1910, they'd reached northwestern North Dakota. Today they have overspread the North American continent. In fact, they are found worldwide, except in tundra, jungle and desert — in other words in almost all places where humans are found.
Familiarity breeds contempt, as the adage goes, and not everybody likes house sparrows. I've known plenty of bird lovers who despised them. Some even destroyed their nests, thinking house sparrows kept other species away.
My bird-loving father forbade this.
House sparrows were abundant around the farm, and I came to appreciate them, so the idea that house sparrows are declining stirs regret.
This was magnified when I read Michael McCarthy's book, "Moth Snowstorm." The book was published by John Murray in 2015. Its subtitle is "Nature and Joy."
McCarthy's thesis is that nature brings joy to humans, and is thus important to our species, but humans often are indifferent and even inimical to nature.
The house sparrow is a case in point.
Once ubiquitous in London, McCarthy found that it has become rare in the city. He conducted a reconnaissance with one of Britain's experts on house sparrows. They found fewer than a dozen birds in the city.
Yet in Paris, a metropolis of similar size, house sparrows remain common.
It's a mystery, just as the decline in house sparrows in Grand Forks is a mystery.
Given that house sparrows are so closely connected to us humans, it's a mystery we should try to understand.
Scientists are working on solving the mystery.
House sparrows are gregarious, and one theory is that the species suffers a kind of colony collapse. As numbers decline, so does nesting success, so that once house sparrow populations begin to fall, they can't easily recover.
McCarthy explores this idea in his book.
It's a sobering thought, considered from the perspective of our own gregarious species.