Mucus-drinking Cowbird

Before Europeans came to North America and cleared forests which modified the environment into the agricultural and suburban landscapes of today, the range of the Brown-headed Cowbird was limited to the short-grass plains where they followed the almost endless herds of American Bison as they fed on the insects stirred up by those wandering behemoths.  Early settlers so strongly associated them with bison that they were called “Buffalo Birds”. Today that relationship still exists wherever limited numbers of bison can still be found.  Antelope Island is one of those places. One of the many challenges facing the cowbird was obtaining enough moisture as it followed the bison herds over the hot, rolling plains.  In late summer several years ago I photographed a cowbird behavior that illustrated one of the ways they solved that problem.   I found this huge bull languishing in the broiling sun next to a boulder that it had been using as a scratching post.  A group of Brown-headed Cowbirds were in the vicinity but at first I wasn’t paying much attention to them.   Then this female (at frame bottom) flew in close…     and began flying at the nostrils of the bull.  Initially I was unsure about what she was doing but she did it repeatedly and eventually it became clear that she was…     drinking the mucus-laden secretions from the bison’s nostrils.  She would actually hover in place as she gobbled down the long, stringy strands of mucus. Not a pretty sight and perhaps a bit unsettling to our human sensibilities but what an incredibly adaptive behavior…

Continue reading