Brown Headed Cowbird: Nature's Welfare Bum

This time of year every morning I'm filled with anticipation, wondering if another bird species is going to arrive today. Lately, I've been disappointed more often than not. So while I'm waiting for the next species to arrive and remind me it's spring, I think I'll talk about the Brown-headed Cowbird, nature's welfare bum.

This bird's call is beautiful. It's very high-pitched. Sometimes the pitch is so high it's almost inaudible. It's hard to describe--it sounds like water in a tumbling brook running over rocks (except that the pitch is many times higher).

Although this picture doesn't do the bird justice, it really is gorgeous. Its head is brown and its body is black, but it also has metallic purple or green highlights that change color depending on how sunlight is hitting it.

But don't be fooled. This bird is an insidious, destructive baby killer. It sneaks into other birds' nests when they're not looking, destroys their eggs and lays its own. The bird that made the nest ends up having to raise the cowbird chicks, who usually grow faster than their legitimate "siblings." Baby cowbirds out-compete their step-siblings, frequently taking more than their share. This increases the risk that the legitimate chicks will not make it to adulthood. Some birds can recognize their eggs and throw them out of the nest. Other birds will leave the area to nest elsewhere when they find their nest has been invaded. But the cowbird is moving into new territory occupied by species that haven't evolved any defense. In these cases, native species can be decimated in just a few years.

The picture above is of the male of this species. The female is a gray-brown, and looks exactly like a female Brewer's blackbird.  They seem to take advantage of this similarity. If blackbirds and cowbirds are in the same area, they can usually be found together in the same flock. In my area, I'm pretty sure that the bulk of the cowbird young are raised by blackbirds.

You can protect your local populations. I've noticed that this bird is not just lazy when it comes to raising children. It's not much of a forager, either.  If you buy birdseed from the store, stop doing it. Most wild bird seed contains millet. Most birds don't like millet. But cowbirds do.  Research the bird species that visit your yard. If you want to feed them, find out what they eat. Purchase that specific type of food. Don't buy anything with the words "wild" and "bird seed" in the title. It's too generic, and will help birds like this gain a foothold. Also, when feeding birds, less is better. Put out only the amount of food that will be eaten in a few minutes. Make sure that the birds are hungry enough to eat whatever falls on the ground, too. Your feeder is not the only source of sustenance for your friends, and if they're leaving food behind they're probably eating more than is healthy anyway.

Your second line of defense is quail eggs. On the day after Easter, go to Walgreen's and buy 5 or 6 Easter egg baskets. Get some straw from the local feed store or dried grass from your lawn, and make nests. Try to put the nests in places that are easy for you to access but seem natural.  Don't underestimate cowbirds' powers of observation: The best time to work around these fake nests is during the night when birds are sleeping. Take a magic marker and make a tiny mark on each quail egg, to be sure you can identify when cowbirds are using your nest. Every other day, put one quail egg in each nest. Just one. Do this until the nests have accumulated 4-5 eggs.

Every day, visit the nests. Move eggs when you do, because that's what the mother bird would do. Quail eggs will start to go bad after a week, so replace quail eggs with fresh ones weekly. If you discover cowbird eggs, mark them and leave them there for a week or so (like the quail eggs, remove them before they go bad). If the cowbird finds out the "mother bird" has discovered her deception, she'll quit using that nest.

I would imagine that after a few years, local bird populations will begin to develop resistance to cowbirds. Perhaps they'll learn to recognize the interlopers' eggs. Or once the baby cowbirds hatch, they'll learn to recognize them and throw them out of their nest. I don't know for sure, because I've only been dealing with them for a few years. But I do know that, though cowbirds are native to North America, their range is growing as they come into contact with humans who like to feed birds. And they are a non-native, invasive species to much of the territory they now occupy. They can have a devastating impact on the species in your neighborhood.

As soon as the cowbirds show up at my house, I'll post some pictures of my stealth nests. I don't expect them here until the beginning of May. I'd like to hear from you about your cowbird woes and any successes you experience. So post a comment, or send me an email.

Bird Embedded in a Rock

I was looking through some pictures I took over the past few months, and I found the following picture. I took it on October 15, 2010. All I did was crop it -- no Photoshop, no extra processing. What you see is exactly what the camera saw: A white-crowned sparrow embedded in a rock.

Sometimes life is stranger than Photoshop!

Coke adds Bird Life

I went to town today and tried to find small jars of strawberry jam. As you might remember from reading my last post, I was going to buy 200 jars and build a custom holder.

Well, it turns out that small jars of strawberry jam are hard to find.  I ended up buying  several large jars of strawberry preserves at Smith's.  When I got home, I made this:

Strawberry preserves are perfect for a feeder like this, because preserves contain lumps of fruit. You can see in the closeup below that I drilled holes in the cap and cut small holes large enough for a tanager's beak around the neck of the bottle. You can also see strawberry jam dripping out. I expected to lose a lot, and that maybe the feeder would be a complete disaster. But I actually lost very little because fruit quickly plugged the holes.  The birds will have to work at it by pulling out the pieces of fruit that are plugging the hole. When they have their fill of jam and fly off, some jam will drip out but fruit will fill the holes again.

I think birds are going to love this feeder. It's practically ant-proof, though there is going to be plenty of food on the ground for the ants to clean up. It's probably too early to put it out, but I want it to be there before any tanagers show up. And I don't know when that's going to be.

Did you know that hummingbirds and tanagers are drawn by color? On their flight in, if they see food, they're going to stop to eat it. And if they stop, there's a chance they won't leave. If I have a western tanager living here this spring and summer, that'll be all the proof I need. And when that happens, I'm going to take plenty of pictures and post them here.

If you put out hummingbird feeders when you start to see hummingbirds, try something different this year. Put out the feeder now, before they arrive. More hummingbirds will stop, and you might end up with five times as many birds as you're used to. Try it!

Get the Western Tanager to Stay

Any day now, I expect this guy to show up and look longingly through the window of the sunroom at the blossoms on my wife's plants. He'll hang around the area for a day or two, then he'll fly off to find a better place to raise his kids.

Tanagers love fruit. If I could give this guy what he wants, I think he might stay. Last summer, I made a temporary jam feeder out of a Bugs Bunny cup:

 

It was hugely successful with the local population. This female Bullock's Oriole spent a lot of time there, as did my population of Black-Headed Grosbeaks. But aside from the fact that it was ugly, being basically a mess of tape, twigs and string, it was tedious to keep clean.

Today I'm going to go shopping for a few cases of strawberry jam. Maybe I can find something cheap at the dollar store. If I can find 200 plastic, 2-4 ounce jars of jam, that should get my feathered friends through the summer. And I'll have it ready before the Western Tanager shows up this time, so that he can feel like he's found a perfect place to raise his family. Then maybe in a few weeks I'll have some nice Western Tanager pictures to add to my collection (and put up here).

The idea is to put up a post outside with a hole drilled in it just the perfect size for a jar of strawberry jam. When they empty it (which can happen in a few hours), I'll replace it with another one and throw the old one away. No muss, no fuss.

I'll post pictures of my new feeder when I'm finished with it. If I can find my jam supply today, I should be able to have everything ready for the tanagers when they show up.

Spring's True Harbinger

The first summer resident to arrive this year is an ash-throated flycatcher:

He showed up on March 15th. This is his third year. I think. The reason this guy lives here is simple: There are a lot of grasshoppers. But it wasn't always that way. I live on two acres. Half of that area has no trees, just grassland with a few shrubs.

I used to mow the whole field, two or three times a year. But four years ago it occurred to me that if there were more grasshoppers, the Cassin's Kingbirds would have more to eat. So I started mowing just the area near the house and leaving the rest for nature.

Two summers ago, a pair of ash-throated flycatchers showed up and had a family. Last year, there were two families. The Cassin's Kingbird population increased too. There are two pairs that hang around my house now (only one pair nests here), and several other pairs in the area that weren't here before.

So now I'm actively managing my grasshopper farm. It covers about 1/2 an acre, and never gets mowed. Not even at the end of the season, because I think the eggs have a better chance of survival if the ground is covered.  And there are other insect eggs on the plants that grow there. Think about it: Birds are only going to nest where they can feed their young. What's better--a manicured lawn, or half a dozen bird species calling your yard home?

I have other stories to tell you later about how I was able to entice other new species, so stay tuned.

Turdus? Migratorius?

Don't believe everything you read in bird books. Just because there are only five subspecies of a bird recognized, doesn't mean there aren't infinite variations in-between.  Take Turdus Migratorius, for example.  (First, why turdus? Couldn't they have come up with a better name? And Migratorius? Well, I can tell you that they don't all migrate.)


I don't normally pay attention to when they arrive, because I have a winter population and a summer population. I'm guessing the summer population arrived around the 7th of March this year. The difference between the summer population and the ones who don't migrate, is that breast coloration on the summer population is a much brighter orange. The scientific name for the species is Turdus Migratorius. I would call natives Poopus Migratorius just to distinguish the two, but I'm no scientist. There are Western and Atlantic Canada subspecies and different hybrids, so who knows?  But many things are possible.

My next post is about this year's Harbinger of Spring.

Eurotrash is back (and so am I)

This past Monday, March 20, a couple of European starlings arrived. They do that every year, hang around my house for a couple of weeks, then move on because I don't feed them. When I used to feed birds storebought feed, these intruders would stick around all summer. Maybe I'm not a true friend of birds, because I consider starlings one of the three illegal aliens of the bird kingdom (the other two are Pigeons and House Sparrows). Their presence is disruptive to native birds, and part of the reason that you have to leave the city to see more than a few species.

I also have problems with brown-headed cowbirds. My cowbird problem is diminished though not gone, and I no longer have to worry about the starlings hanging around more than a couple of weeks. There are things you can do to improve your bird variety, and I will be talking about things that I do in this blog.

Today I'm going to make several entries, because every year I want to start tracking arrival and departure dates for birds, and every year I forget to. This year I'm going to stick to it.

I am an avid amateur photographer. Feel free to emphasize the amateur, but I do get a few good shots, and I'll be posting them here frequently.  My success is less technique and more patience, and I'll be talking about that as well.

For now, I'll move on to my next entry, robins.