Where are the birds? Many factors can contribute to drop in avian numbers

I made a pretty safe prediction in my last column: A bird will surprise you in 2020.

It already happened to me, on the day after Valentine's Day.

I had just entered my car about 9 a.m. outside the YMCA in Glen Ellyn. At that moment, a large dark bird in the distance caught my eye. It was flying low, partially obscured by the trees north of the building. My back seat binoculars confirmed it: an adult bald eagle!

I'd never seen an eagle in Glen Ellyn, my home for almost 23 years. The experience gave me hope of someday spotting one from my yard.

Unfortunately, hope is about all I've had in the backyard this winter. Feeder activity is super slow, with dark-eyed juncos the most reliable customers. Variety is down only slightly, but the volume of birds is disturbingly low. I long for a good old-fashioned feeding frenzy.

It's not just me. I contacted Wild Birds Unlimited in Lisle.

"It's been kind of strange," store owner Brian Neiman said. "The majority of customers are reporting fewer birds so far this winter, while the remainder are reporting average to above average activity."

Seed tonnage at WBU is somewhat below last year. Neiman said the relatively mild winter and infrequent snowfall makes foraging easier; natural food sources are more available.

A few birders told me they see lots of birds one day and none the next - a frustrating pattern of inconsistency.

Personally, my biggest disappointment is the absence of red-breasted nuthatch - my favorite backyard bird and the main reason I hang a peanut feeder. The cone crop in the boreal forest is reportedly strong, so the species hasn't wandered south in search of food.

The same holds for the winter finches, such as common redpoll, pine siskin, purple finch and crossbills. This is not the "irruption year" that birders covet, when these occasional visitors from the North Woods arrive in numbers, bringing color and excitement to our feeders, parks and forest preserves.

A range of factors can explain "no-bird syndrome" in the backyard. Weather, time of year, feeder placement and seed freshness, for example. Predators, too - a persistent Cooper's hawk or prowling house cat will quiet things down in a hurry.

But this winter, with the apparent widespread shortage of birds, something else must be going on. I did some searching online.

"Unless there has been a significant change in the immediate area of a feeder, or in the local habitat, the answer will usually be explained by population dynamics," according to the Mass Audubon site. "Populations of all songbirds are subject to natural fluctuations from year to year."

So the good news, besides the easy winter, is that we are probably doing nothing wrong. Birds are most likely not flocking to fine-dining feeders and 5-star heated bird baths with towel service just down the street. There may simply be fewer birds in the region. And those present, like Neiman said, are less reliant on our handouts.

I see my feeders as half full, not half empty. But it's hard to be positive when the view from my kitchen window shows seed levels virtually unchanged from the day before.

You might guess where I'm going with this. The feeder slowdown this winter - at least in my yard - follows the recent release of that bombshell report in the journal Science.

Bird populations are crashing. Analysis of more than 50 years of data showed a 29% drop in total bird numbers in the U.S. and Canada since 1970 - a staggering loss of 3 billion birds. Visit 3billionbirds.org for details, along with things we can do to help.

Ecologist and bird bander Julie Craves writes the popular "Since You Asked" column for BirdWatching. In the magazine's current issue, she said readers in New Jersey, New York and Pennsylvania wrote to ask why their feeders are deserted.

While acknowledging that many bird species are declining, Craves cautioned "against drawing any conclusions about general population status from hyperlocal observations."

She's right, of course. What we're seeing or not seeing in our backyards should not be directly connected with the "3 billion birds" report. It's not that simple.

It's obviously concerning, however, that some species we've always regarded as common are gradually fading away. Among them: blue jay, Baltimore oriole, dark-eyed junco, rose-breasted grosbeak and white-throated sparrow. I'm not in a panic state, not yet, but I'm sure looking at birds a little differently these days. Every one that comes around seems more like a gift.

• Jeff Reiter's column appears monthly in Neighbor. You can reach him via his blog, Words on Birds.