Special to The Record | USA TODAY NETWORK - NEW JERSEY

   In recent days, one of my favorite winter birds has probably arrived in a backyard near you.

   I am referring to the white-throated sparrow, the stout-hearted little brown bird from the north that hangs out under area feeders from now until spring. 

   One reason I like these sparrows is they actually have white throats, which makes them easy to identify at a glance. White-throats also sport a patch of yellow between the bill and each eye, another easy field mark.

    Beyond those easy-to-spot white throats and yellow lores, things get exceedingly complicated with these sparrows. If you look very closely, you might notice that some have white stripes on top of their heads and others have tan stripes. 

   The plumage difference is not a question of male vs. female. Both sexes come with either head stripe. Rather, the males of one plumage breed almost exclusively with the females of the other plumage. 

   Here’s why the opposites attract (and I am not making this stuff up): Because of a certain chromosome variation, the birds with the white-striped heads, are promiscuous and lousy parents. The birds with the tan-striped noggins are monogamous and devoted parents. 

    Because of their superior chick-raising skills, tan-striped males are the mate of choice for both the tan-striped and white-striped females. But because the white-stripe females are more aggressive, they get to pair off with the tan-striped males. 

    That leaves the white-striped males to pair off with the tan-striped females, and – given their promiscuity – often more than one.  

    Studies have shown that roughly 95 percent of the white-throats pair off in this opposites-attract fashion and that they produce white-striped and tan-striped offspring in equal proportion, thereby maintaining the balance between the two morphs. 

   Since we see the white-throats in non-breeding season, their sexual preferences are rarely on display, which may be just as well.

    One more thing: the white-throat’s trademark call, “Oh, Sam Peabody, Peabody, Peabody” is typically a sign of spring. Recent studies have found that white-throats have been abbreviating their call to “Oh Sam Peabah, Sam Peabah, Sam Peabah.” Not sure if they are in more of a hurry these days but maybe it’s related to their complicated private lives. 

   In any event, I’ll bet the late great naturalist Edwin Way Teale would still say: “For me all the frail, enduring beauty of the world finds its voice in the song of the white-throat.”

   Field notes: Now through mid-November is prime time in North Jersey for migrating rusty blackbirds. The species’ population has plummeted a staggering 90 percent or more since the mid-1960s due to habitat loss and other factors. 

    If you see any, report your sighting to ebird.org.

       The Bird Watcher column appears every other Thursday. Jim’s latest book, "The Screech Owl Companion,"  was published last week by Timber Press. Email Jim at [email protected].