Bald eagles could be the bird world鈥檚 version of heavyweight boxer Mike Tyson. The eagle is a big bruiser of a bird. It bullies other birds, steals meals and scavenges whenever it can.
Yet, during mating season, incongruously thin, flutey, soprano-sweet nuthin鈥檚 emerge from the predator鈥檚 slasher beak. The voice belies the bird鈥檚 reputation and lifestyle.
In addition to eagles鈥� springtime singing along the Gorge Waterway, I鈥檝e noticed local ravens pairing up and chortling among themselves. Robins now strive to out-chirp each other, varied thrushes rend mornings with off-key whistles and towhees mimic hinges in need of oil.
The chestnut-backed chickadee has changed its tune from 鈥渃hickadee-dee鈥� to its 鈥淗ey, baby鈥� pickup line. And the 91原创 wren鈥檚 lovelorn avian arias make me wonder how these tiny opera singers can sustain so many trills and arpeggios with just one breath.
It鈥檚 easy enough to guess what they鈥檙e singing about right now. Something along the lines of 鈥淟et鈥檚 make beautiful music together鈥� to the ladies, and 鈥淕et off my beat or I鈥檒l beat you up鈥� to other guys. These themes play out in human songs as well, as 91原创 Opera Victoria鈥檚 performance of Tosca demonstrates this month. They also cause many of the same emotional responses in both animals.
Apparently, the female white-throated sparrows breeding in B.C.鈥檚 forests respond to the songs of male sparrows in the same way that humans respond to pleasant music. The reward centres in the sparrow brains light up just as ours do, say researchers who scanned the bird brains.
Male sparrows, on the other hand, find songs of other males alarming and stressful. Their brains鈥� fear, loathing and anger centres light up, as ours do when we hear the da-dum da-dum sequences in scary-movie soundtracks, or when we face down opponents.
Birdsong and human language share other characteristics. Rules govern how birds string notes and trills together, just as grammar and syntax regulate how we use words and construct sentences. In one example, brain researchers remixed Bengalese finch song three ways, and played the re-ordered recorded chirps back to the birds. The birds ignored two revised tunes, indicating the original message survived the remix. They became agitated with the third tune, however, suggesting the new tune didn鈥檛 make sense in Finch.
The birds鈥� reaction may resemble griping by a certain writer when she鈥檚 confronted with text messaging: Is that supposed to be 鈥渓ots of luck,鈥� 鈥渓ots of love鈥� or 鈥渓augh out loud鈥�? And what is happening to spelling and grammar these days, anyway?
Some birds sing to their unborn chicks. I know human mothers-to-be who play Mozart to their belly-babes in hopes of giving the children a possible edge in musical, mathematical or just plain intellectual genius. Whether the strategy works in humans is unclear, but Australia鈥檚 fairy wrens sing prenatal lullabies to avoid being saddled with the care and feeding of chicks of freeloader species.
Yes, slackers exist even in Birdland. Cuckoos and cowbirds, for example, avoid parental responsibility by laying their eggs in other birds鈥� nests. Their eggs hatch first. The chicks then monopolize their unwitting surrogate parents and often trample or eject adoptive siblings from the nest.
Meanwhile, the deadbeat parents are out tweeting it up at cuckoo/cowbird parties.
In a variation on the strategy that thwarted the abduction of a young Toronto girl last month, the fairy wrens avoid exploitation-by-cuckoo by teaching secret passwords to their own unborn chicks. In Toronto, the stranger who tried to pick up the 10-year-old after school was unable to provide the password she and her parents had arranged. In fairy-wren nests, if a new chick doesn鈥檛 include the secret password in its calls for food, the wren parents may abandon the nest and start over elsewhere.
So step outside and listen to the chirps, whistles and twitters going on around you. Even if the singing is over your head and beyond your grasp, the bird banter may include the same conversations you鈥檙e having with your own family, friends and acquaintances.
