Return of orioles bring splash of color
While wandering around the backyard picking up sticks recently, I happened to notice the conspicuous pouch-shaped nest of a Baltimore oriole hanging in the leafless canopy of a nearby mature aspen tree. A fragile looking nest that swayed back and forth in the wind, it seemed so obvious that I wondered why I hadn't noticed it sooner.
"Ahh," I thought, "the nest was probably built brand new last spring when the tree was completely leafed out."
I observed my first oriole on the afternoon of May 9. The telltale whistle of the bird alerted me and so I began searching the treetops for the beautiful orange and black plumage pattern. Upon spotting the oriole, I promptly went to the house to retrieve the bag of frozen oranges that I had been hoarding since late last fall. A few moments later after I had halved a few, I returned with the orange halves and skewered them onto some of the nails I had driven into oak trees over the years for just that purpose.
Indeed, while we here in the Northland rarely see or hear the wonderful whistled songs of singing northern cardinals, we do have one bird that comes pretty close to not only the striking beauty of a cardinal, but one that can belt out an aptly competitive tune, too. The handsome and animated Baltimore oriole has returned to our northern towns and country woodlands.
I normally hear my first oriole before I actually observe him. And it has always been a male oriole that I observe first, not a female. Like many migrating birds, males often are the first to arrive at the northern breeding grounds, and the Baltimore oriole is no exception. The feisty fellows are searching for likely territories they can claim as their own and are soon chasing after other wayward males daring to enter their respective domains.
Belonging to the family Icteridae and related to blackbirds, grackles, and meadowlarks, orioles are considered to be arboreal, or tree-loving icterids. Like many other neo-tropical migrants, orioles arrive here in northern Minnesota by mid-May. Neo-tropical migrants, which also include a host of other birds such as warblers, vireos, rose-breasted grosbeaks, ruby-throated hummingbirds, and others, come from as far away as southern Mexico and South America.
Depending on when your bird book was published, nine species of orioles occur in North America. Our most common oriole here in Minnesota is the Baltimore oriole. Again, depending on the bird book, the Baltimore oriole is sometimes classified as a "race" of the so-called "northern oriole." In some bird field guides the northern oriole is comprised of two races: the Baltimore and the Bullock's. But as far as I know, the Baltimore and Bullock's orioles are widely recognized as separate species - again.
The reason for the taxonomic flip-flop has to do with these species of orioles' propensity to hybridize and the obvious confusion such interbreeding poses for birders and ornithologists. Where their ranges overlap, the Baltimore, an essentially eastern oriole, regularly hybridizes with the essentially western Bullock's oriole and, hence, the problem.
Are the Baltimore and Bullock's orioles separate species or not? One of the standards of species separation is the inability to interbreed, and since they can and do interbreed, the two are obviously very closely related and, perhaps, should not be considered separate and unique species.
All I know is that the orioles that show up every year in Minnesota are handsome and fascinating birds. The loud and clear flute-like whistle of the Baltimore oriole is a welcome song of backyards and woodlands alike. I even find their annoying chatter-call a joy to hear and something I look forward to each and every spring.
One of the most remarkable aspects of the Baltimore oriole and other New World orioles, are the nests they build, or better said, weave. Baltimore orioles weave elaborate hanging nests resembling pouches from grasses and other vegetation. The nests are normally hung from the outermost, thin branches in the canopies of mature hardwood trees. These durable, suspended nests are the result of tightly woven construction, strong knots, and superior building materials.
Seeing such intricate nests have always impressed me. How, I wonder, can a bird - any bird for that matter -possessing only beak and feet build such elaborate nesting structures that human hands, fingers, and opposable thumbs would have great difficulty duplicating? Nature is a wondrous thing to be sure.
If you don't already own an oriole feeder, now is a good time to purchase one or two and fill with sugar-sweetened water. One part sugar to three or four parts of water will work just fine; no need to purchase expensive "nectar" mix, nor is it necessary to add color. Or, slice up some oranges and place the slices outdoors onto nails driven into the trunks of trees or placed inside a bowl on something visible to you and your birds. Grape jelly and other fruit jam work great too.
Without question, marveling at the color and antics of your visiting orioles is something to savor every spring and summer as we get out and enjoy the great outdoors.
Blane Klemek is the Bemidji area assistant wildlife manager, DNR Division of Fish & Wildlife. He can be reached at firstname.lastname@example.org.