One of the best things about moving into a new house is that you get to build a new backyard bird list. Some birders are obsessive listers whose interest in birds seems to begin and end with check marks. My own lists are more whimsical than obsessive. I have an interstate list, for example. The rule is that the bird has to be identified from the car while moving at the speed limit. (That's me moving at the speed limit; the bird can be perched on a tree limb.) The important part is that rest-stop birds don't count.
The last time I had a backyard in Chicago I ran up a list of 55 species, including sandhill cranes. The rule wasn't that they had to be in the yard but that I had to be able to see or hear them when I was in the yard. You may ask who makes these rules. Me of course. And I bow to no one in my ability to follow utterly arbitrary rules, as long as I get to make them.
Our new backyard looked like a birdy place even in December when we arrived. We have two cherry trees. A huge mulberry in the yard next door shades our garage. The yard beyond that is heavy on shrubs, and just across the alley are a couple of huge old cottonwoods. House sparrows nest under loose shingles on the house next door, so we always have a noisy crowd of them around.
My list started with the ubiquitous alien three: house sparrow, starling, and rock dove, otherwise known as pigeon. Crows were hanging about from the beginning, and the occasional ring-billed gull flew over. My counting got a boost when a friend gave us a bird feeder as a housewarming gift. It was a simple little box with clear plastic sides and a flat roof. You poured the seed in through a hole in the roof, and it came out the bottom in two little troughs that ran the length of both sides. I suspended it from a cherry branch and filled it with seeds.
Naturally we got squirrels. Four of them. They hung from the branch above, quite happy to eat upside down, and they went through a lot of seed. Your average house sparrow weighs about half an ounce. It lives a high-energy life, but its food needs are nowhere near the requirements of a four-pound squirrel. A squirrel would settle itself in and eat for several minutes at a stretch. This not only runs up the birdseed bill but also effectively keeps the birds away until the squirrel is through.
I'm pretty tolerant of animals, so I didn't get too bent out of shape about our greedy sciurids. But eventually one of them knocked the feeder off the end of the branch. It got all busted up, which effectively ended our bird feeding.
But before this calamity occurred we were drawing a lovely pair of cardinals, some house finches, a couple of chickadees, a variable number of juncos, and the occasional mourning dove. The juncos fed mainly on the seeds knocked to the ground by the squirrels.
Our backyard is unusual for Chicago in that it has a slope. The house is on high ground, but things fall away noticeably toward the alley. This slope is quite visible in all the backyards for a block in either direction. We are on Hermitage, 1700 west, just south of Devon. I thought we might be at the edge of the old beach ridge that Ridge Avenue follows north into Evanston. I checked in J. Harlan Bretz's Geology of the Chicago Region and discovered that we are in fact at the eastern edge of the Rosehill Spit. We not only have a slope in our backyard, but that slope has a name. How many people in Chicago have a named geological feature on their property?
Just 2,000 years ago our backyard slope was the shore of a lagoon that connected with Lake Michigan. We own shoreline property. We just got into the game a little late.
The crows we saw hanging about the neighborhood have a nest high in one of the tall cottonwoods across the alley. Right now it looks like they are sitting on eggs. They seem to trade off the nest-tending duties, and they are quite aggressive about driving away other crows. I frequently hear them making a staccato clicking noise--I suspect they do it by opening and closing their beaks--and I am wondering if this is some sort of communication between the two birds in the nesting pair. In the high winds that come with spring in Chicago the nest swings alarmingly. I wonder if crows ever get motion sickness.
With our feeder destroyed, the crowds thinned out some in our backyard, but since migration got under way we have been adding new species on a daily basis. A few grackles got here before the end of the feeder. They helped themselves to our seed, and it looked like they were eating almost as much as the squirrels.
A pair of mallards flew over one day, and the neighborhood kestrel sometimes perches in the tall cottonwoods. A friend of mine who lives a couple miles west of here has a sharp-shinned hawk coming by her feeder on a regular basis. Like lions hanging out near a water hole, raptors think of feeders the way people think of supermarkets.
The arrival of our first hermit thrush along about the middle of April let us know that the songbird migration was truly under way. These relatives of the robin--which got here in early March--pass through here on their way to the North Woods. They are the first of the spot-breasted thrushes to show up. Ground feeders, they scour the flower beds for early insects.
Our cherry trees came into flower during the first weekend in May, and they are a glorious sight. We were worried about pollinators for the blossoms. We don't seem to have any honeybees in the neighborhood, and in spring we might be a little short of the number of bumblebees that would be needed to do the job. The whole hive of honeybees lives through the winter, but only the queen survives in a bumblebee colony. She sleeps through the winter underground and emerges early in spring and starts feeding. As her eggs start to hatch, she has to feed the whole lot until the first generation reaches adulthood. After that she has some help, and each succeeding hatch has more adults to care for it. How many cherry flowers could one bumblebee pollinate?
The answer seems to be quite a few. Your bees are famous for diligence, and the two queens that feed in our backyard are hitting a whole lot of flowers.
Birds appear to be helping. On May 7 we had a major wave of migrants hit town. At one point I looked out my office window, and there in the closest cherry tree, no more than 15 feet away, were six male northern orioles, a catbird, a yellow-rumped warbler, two Cape May warblers, and a ruby-throated hummingbird. They were all probing the cherry blossoms. I suppose they were getting nectar and possibly small insects that were also looking for nectar, but I expect that they were doing some pollinating as well. They all worked very neatly and carefully, as if anxious not to damage the flowers. I'm thinking of selling our cherries like a specialty honey. Instead of "orange blossom honey" or "basswood honey" we will have cherries pollinated by Cape May warblers.
Those Cape Mays have me really interested. They hung around from Wednesday until Saturday, feeding furiously on our cherry tree the whole time. It makes you wish that somebody could radio tag a few of these birds in, say, Guatemala, and follow them all the way to their nesting grounds up near Lake Superior. You would have to have a really small transmitter, since a typical warbler weighs about a third of an ounce. If you attached something that weighed more than a tenth of a gram, it would probably be such a burden that the bird would have little chance of making the long, arduous journey to the north country.
What I would like to know is if this sort of long stopover is typical. Do the birds regularly fly night after night or do they usually make a long flight followed by a few days of rest? Of course a lot depends on the weather. They don't fly into head winds if they can avoid it. But would they pass up a favorable wind if they needed more R & R? They are under heavy pressure to get up there and find a good nesting territory, but you can't nest if you die before you get there. My suggestion is for drastic reductions in Pentagon spending and a diversion of engineering talent to the creation of extremely tiny radio transmitters.
Until that happens I'll just have to enjoy the birds as they pass by. Yesterday I added house wren, gold½nch, and Nashville warbler to my list, bringing me up to a total of 40 species, and this morning the cherry tree was feeding an orange-crowned warbler. The ½rst 41 are always easy, but the migration still has a few weeks to run. Maybe I can hit 50 before June 1. i