Dear Bird Folks,
Recently, I heard what I thought were both a Tufted Titmouse and a Carolina Wren singing nearby. Then I discovered the sounds were coming from two different mockingbirds instead. Any explanation why they are singing this time of year?
– Gail, East Orleans
They’re good, Gail,
The Northern Mockingbird does over two hundred dead-on imitations. And now that I think about it, it probably should be called the “mimic-bird” because it mimics and doesn’t “mock.” Mocking implies ridicule. (I don’t know who comes up with these names, but that person deserves to be ridiculed.) Mockingbirds have fooled plenty of birders and non-birders over the years, so thinking you heard a titmouse and a wren is totally understandable. There is, however, one way to know which is the real bird and which is Memorex…I mean, which is the mockingbird. I’ll explain how to do that later and, if I have room, I’ll also explain the Memorex thing.
As you probably already know, songbirds, especially the males, are highly vocal in the spring. They sing in order to attract a mate and to announce their territories. When their breeding season ends, so does their singing. The birds now make an effort to become less obvious, while they grow a new set of feathers for the coming winter. In fact, fall tends to be a quiet time for birds. A few species, especially owls, are the exception. The Great Horned Owls in my area are chatting up a storm right now. Why? They remain on their territories throughout the year and don’t want any young punk owls moving in on their turf. Surprisingly, the little Carolina Wren is doing the same thing. Wren couples also remain on the same plot of land 365 and they don’t want any usurpers either. Mockers do it differently. In the spring they defend their breeding grounds and in the fall they defend their eating grounds. When they find a patch of food (usually berries), they’ll sing to keep others away. If singing doesn’t work, they’ll get physical, but not the Olivia Newton-John kind of Physical we used to listen to on Memorex tapes. It’s much more serious.
One fall morning I was hiking in a remote part of the Cape, when I spotted a mockingbird on top of a berry bush. This poor bird had picked the wrong bush to defend, because ten feet away was an old shed. By itself the shed was harmless, but it also happened to have a small window and once that mocker saw its own reflection in the window, the fight was on. It attacked the “other bird” relentlessly. I watched the skirmish until I eventually lost interest, but the mocker never did. It just kept attacking. That was in November of 2014 and as far as I know, that battle is still going on.
One hundred years ago mockingbirds were rare in Massachusetts. Our winters were just too tough for these (mostly) non-migratory birds from the south. Then someone (the USDA) thought it was a good idea to introduce multiflora roses from Asia. The thick shrubs formed attractive barriers in pastures and along highways. But, and stop me if you’ve heard this before, as is the case with most exotic species, the quickly spreading roses eventually became an environmental problem. Surprise! Today multiflora roses are considered to be an invasive plant and a bad mistake, but don’t tell the mockingbirds that. They love the tiny rose hips that remain on the shrub’s branches throughout the winter. As the roses proliferated into the Northeast, so did the mockingbirds, and as the mockingbirds increased, so did the roses. Rose hips are filled with seeds and when the rose hips went in one end of the mockingbird, seeds came out the other. By pooping out multiflora rose seeds, the birds helped to increase their own winter food supply. Not only do the mockingbirds enjoy the rose hips, but other species do as well. This begs the question: If various creatures are able to live off multiflora roses, where’s the downside? This is the question the USDA should have asked before bringing the exotic plant into the country, but you know how bureaucrats are. Thinking things through isn’t their strong suit.
Introduced plants thrive in North America because they have no enemies. Our insects can’t digest the leaves of most foreign plants, so the plants thrive while our insect population wanes. Humans have no special love for bugs, but baby birds depend upon them for food, and fewer bugs eventually mean fewer birds. If you have any friends who worked for the USDA in the 1930s, give them the stink eye. They’ll know why.
After a period of growth, the Cape’s mockingbird population has been in decline, Gail, so you are lucky to have seen two of them, even if they did fool you at first. Finally: Here’s how to tell if you are hearing the real bird. Mockers typically give a short snippet of another bird’s song and then repeat it four or five times, before mimicking a totally different bird. In other words, if you hear a wren singing but then it suddenly turns into a cardinal or a jay, you have a mockingbird in your yard. As for Memorex, it was a cassette tape company that once had a catchphrase asking, “Is it live or is it Memorex?” Apparently, people could definitely tell the difference because Memorex went of out business in 1996. Cassette tapes are one of those things that seemed like a good idea at the time…kind of like the multiflora rose.