One of the most remarkable wildlife sights I have ever seen happened by chance on the drive back from Yellowstone last month. Initially it started off with a relatively small flock of about 50 snow geese passing overhead. Soon I noticed another flock and then another, but it wasn’t until I glanced west to take in the Rockies on a clear, beautiful day that I saw almost the entire western horizon dotted with these geese! I had heard about the snow geese migration, but I had never witnessed it before. To see hundreds of thousands of birds in the sky at once was so amazing I had a hard time keeping my eyes on the road. As luck would have it, a large majority of them were headed in our direction. No more than a few kilometers up the road, thousands of these birds starting landing in a farmer’s field. This must have been a cue for the rest of the massive flock to land for the night, because within minutes there were thousands upon thousands of snow geese fluttering to the ground while making their distinctive calls along the way. I found a side road to turn off onto and started firing off photos. In the below photo a small fraction of the goose flock flew overhead. See if you can spot another species of bird in with the geese.
A few minutes later, about a 1 kilometer stretch of the field was covered with these geese. They continued to honk as they gobbled up grain, which prompted the geese still in the sky to circle around and start landing as well. Within 10 minutes there were hundreds of thousands of birds on the ground!
There are a few examples of animals that have adapted to living with the billions of us! Snow geese are one of these. Their population has grown to over 5 million breeding birds, a 300 fold increase since the 1970’s! Much of this has been attributed to the rapid agricultural expansion that has occurred in the west, creating a smorgasbord of food for these birds as they make their way to and from the Arctic every Spring and Fall. Other possible factors include rising Arctic temperatures. However, that only partly explains their population expansion. A lot of it also has to do with their behavioural adaptation to a changing environment. Historically they fed in marshes but a few of the smart ones or maybe by chance some stumbled across the fact that people leave tonnes of uneaten food in the fields every year. With the flat rolling prairies it’s also easier to see predators approaching from a distance or from the sky. This new-found migration strategy must have been passed along to the point that almost all the geese stop over in these fields to fuel up before continuing their journey.
Below is a photo of the organized goose chaos. Multiply this photo hundreds of times and you will get an idea of what it was like to be next to this massive flock. It’s remarkable that they manage to coordinate their movements enough that they are able to land, take off and feed without colliding into each other and plummet to the ground. It certainly is an experience I will never forget.