Extraordinary Beaks
by Iva Petrovchich, Pandemonium Aviaries intern
One of PeruNature’s partner groups is Pandemonium Aviaries, a 501(c)3 non-profit bird sanctuary where exotic endangered birds are being kept and bred until they can be reintroduced to their native communities. Based in Silicon Valley and founded in 1996, Pandemonium Aviaries has helped upwards of 350 birds and continues to grow through both local and worldwide support. Among the numerous aviaries, there is a small population of macaws that dance, sing and play.
For those of us that started our relationships with birds tentatively and with the slightest tinge of fear accompanying the awe, noticing the beaks on macaws is an automatic first instinct. And why wouldn't we? They're something amazing. The most conservative estimate would have macaw beaks exerting a pressure of over 500 pounds per square inch, and they easily crush Brazil nuts. If that doesn't intrinsically reinforce being over cautious, nothing will.There are a lot of uses for beaks that come quickly to mind, in addition to crushing Brazil nuts or lunging at an overeager acquaintance to assert their boundaries. Fighting, foraging, killing prey, feeding their young, using objects, luring potential mates-- things we have come to expect. But perhaps, we are missing a more delicate feature of beaks.
When comparing the native sparrows, finches, and Jays that visit Pandemonium Aviaries to the enormous-beaked birds that enamor visitors through Peru Nature, the idea that birds from warmer climates have larger beaks than those from colder climates is obvious. But why? What accounts for the huge beaks of the toucans, for example, that one can see when taking a trip with Peru Nature?
One reason for these beak sizes may be that toucans have shown the ability to regulate their temperatures with their beaks. Considering that birds already operate at a higher metabolic rate than mammals, keeping cool is a very important process and these thermal windows are critical. Luckily enough, toucan beaks are richly lined with blood vessels. By being able to modify the blood flow to their beaks, they can control how they will radiate body heat. When the toucans overheat, blood rushes to their beaks; when the weather is colder, they restrict the flow. In infrared pictures, you can see the toucan's beak light up like an incandescent bulb when they get warmer than their liking. In fact, regulating blood flow in their beaks can account for 30% to 60% of their body's total heat loss, and it is estimated that toucans can lose as much as four times its resting heat through their beaks.
While the beaks of tropical birds may register with us first and foremost for their power and strength, we must also recognize that they are even more complicated than we may have anticipated. And while the thermoregulation studies haven't quite panned through with macaws to the same extent as they have with toucans, I can't help but admire at the macaw smiles at Pandemonium Aviaries when they take a break from dancing.
