Dear Bird Folks,

For the last few weeks crows or grackles (I don’t know how to tell which is which) have been digging up my yard. I don’t mind because it’s a Cape Cod yard and survives with no attention from us. However, I would like to know what they are birds digging for.

– Gwen, N. Eastham

Good for you Gwen,

Aren’t Cape Cod yards the best? They don’t need maintenance. They also don’t need fertilizer to make things grow, or pesticides to make things die, and the birds love them. That’s the good news. What caught my eye was your line about not knowing the difference between a crow and a grackle. Come on Gwen. It’s easy. It’s like telling a sugar spoon from a soup spoon, or a beagle from a bulldog, or me from Hulk Hogan. Although, a lot of people have trouble with that last one.

Crows are big birds. They are by far the largest songbird you will see on Cape Cod and, with exception of its jumbo cousin the raven, the largest songbird in North America. The Common Grackle is a lightweight compared to the American Crow. The crow tips the scale at four times the grackle’s weight, has double the wingspan, and is nearly a half-a-foot longer. Crows have thick bills, stalky bodies and strut around like bouncers at the Land Ho. They are black all over. Their feet are black, their legs are black, their bodies are black, their bill is black, and if you happen to see one yawning, the inside of the mouth is black.

Grackles on the other hand have much more slender bodies, looking anorexic by comparison. At distance they may seem black but if any light hits their feathers they will show a purple-greenish iridescent bronze. Got that? Their eyes aren’t dark but bright yellow, making them look like a battery-operated toy. Crows seem to walk along the ground in slow motion, calculating every move. Grackles are fidgety. They appear to be upset with all the other grackles in the flock, constantly squawky and squealing at each other. Both birds are likely to come to our backyard looking for food, but a flock of grackles maybe in the dozens or even hundreds. A backyard crow flock is usually much smaller in number.

Now that we have completed Grackles vs. Crows 101, let’s move on to why they were digging up your yard. My first thought is that the birds were looking for some kind of insects, but since I’m not a bug-ologist I had to ask for help. I contacted Professor Dave Simser at the University of 4 Cs. The good professor agreed with my thoughts. He is obviously a very smart man.

Early in the year beetles lay their eggs in the soil. Tiny larva, or grubs, emerge from the eggs and steadily grow by feeding on the roots of grass and other plants. The grubs remain close to the surface until the cold weather forces them to burrow deep to escape the coming winter. Late summer and early fall is prime time for the birds to go grub hunting. Towards the end of our conversation Professor Simser told me exactly which species of beetle larvae the birds were most likely digging up. I’d be happy to pass that information on to you, but by that time my ADD had kicked in and I started thinking about Christmas and my letter to Santa.

Last week I spotted a small flock of crows walking through a yard in Eastham. Remembering your question, Gwen, I stopped and watched them feeding. They were indeed digging into the soil and would occasionally come up with something that looked good and squishy. I sat studying the birds through my binoculars for quite awhile until the paranoid homeowner had had enough of me and turned on the lawn sprinklers. That happens to me a lot.

I’m not sure which flock was digging in your yard, Gwen. Both grackles and crows are around Eastham in the fall and both are always on the move looking to exploit a new food source. Which ever bird it was, it was doing you a service by ridding your yard of grubs that could cause harm to any plants you may have in your yard. And you are doing the birds, and all of us, a service by having a pesticide free Cape Cod yard.

Now that I’ve answered your question, you need to do me a favor. Take a few minutes to study the difference between the grackles and crows. They are not difficult to distinguish. The American crow is big, bulky and all black. The Common Grackle is slimmer, iridescent black and has a bight yellow eye. If you see a bird that is all black, overweight and has red bandana, it’s not a bird at all but a black lab that has wondered across the border from Wellfleet. Don’t be afraid, just toss out a few tennis balls and no one will get hurt.