What do you think of when you hear the phrase “bird brain”? We’ve been taught to think of that as an insult. Birds have small brains and that can’t be good right? Well to put it bluntly, that’s just plain WRONG. Birds are capable of amazing things and the heart of that capability comes from their tiny little brains.
Let’s talk navigation. We humans have developed all sorts of fancy gadgetry to help us get around. We have an intricate network of roads to travel on, GPS to tell us where to go, and radar to let us know what the weather will be like along the way. But birds, well they have none of that and yet many of them undertake an incredible journey twice a year flying thousands of miles across continents and mountain ranges and even oceans. Let’s put aside the fact that they have the physical ability to do that for a minute and think about how it is that they know HOW to do that.
Birds are hatched with an innate ability to navigate. Research has shown that they have a built in GPS that uses the sun and moon and stars or on cloudy days the landform (mountains and coastlines) and sometimes even magnetic fields to find their way from where they breed to where they spend the winter and back again. And we’re not talking about a trip over the fields and through the woods to Grandmother’s house. We’re talking about a trip that could be from a forest in Canada to a forest in Costa Rica. That would be a Northern Waterthrush that is about 5 inches long and weighs a half an ounce. Or maybe you’re a Red Knot, a medium sized shorebird (approximately 60 grams) that breeds in the Arctic Circle and spends the winter at the tip of South America. That means every year you have to fly 9,000 miles between where you make babies and where you winter, much of it over open ocean. How do they find their way? It’s all in that tiny bird brain.
And here’s another question. How do birds know how to negotiate weather systems that could easily kill them when we humans can’t seem to predict the weather with much certainty even with our fancy radar and satellites and who knows what else? Although birds do get caught in storms, for the most part they are master weather forecasters. In the fall, they know how to negotiate frontal passages using the tail wind created by the front’s north winds to give them a boost on their southerly journey. Think that’s something? Consider this: Hope the Whimbrel (a large shorebird) flew into Tropical Storm Gert over the coast of Novia Scotia in August 2011. She flew into high headwinds for 27 hours and averaged only 9 miles per hour but once through the storm, her flight speed increased to more than 90 miles per hour as she was pushed south by the significant tail winds produced by the storm. We know this because she was wearing a satellite transmitter that tracked her movements. Since this time several other Whimbrels have been tracked flying through hurricanes and there is some speculation that the birds know how to use the significant winds produced by these storms to aid their migration. What a bird brain!
There’s more to bird brains than navigation but it will have to wait until another article. Next time someone calls you a bird brain, you can raise your shoulders high and think how smart you must be to have a brain like that.
By Dr. Susan Heath
part 1 of 2