Can geese cause wake hunting?

Adventures in Bird Language
Written by Tamara Anderson
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It was still dark when everyone arrived at the shore of Guelph Lake on October 25th. Anticipation hung in the cool, autumn air. What will the birds be up to this morning? As the sun rose in the eastern sky, we each set out to find a location to sit and observe the language of the birds. At the beginning of the 7:00am sit, the wind picked up and crows called from the farm fields in the northwest. Were they preparing for a morning meeting? As the wind calmed, a small flock of dark-eyed juncos flew into the cedar trees near the nature centre bird feeder. A red squirrel alarmed from a walnut tree close by and then proceeded to eat his nutty breakfast. The events that followed proved rather interesting. A mourning dove flew north from the lake edge, to the bird feeding area. Shortly after, a noisy flock of Canada Geese took off from the water and flew westward. A silhouetted shape emerged from the shoreline and flew directly overhead, following the path of the mourning dove. Ann identified it as a Cooper’s hawk. I watched the accipiter silhouette fly just behind me; its wings had narrowed and were tucked in close to its body. I was amazed how its flight pattern and shape matched that of a large mourning dove. Who would have thought that Cooper’s hawks can be shape-shifting ninjas? I read in Jon Young’s book What the Robin Knows, that hawks and other animals have an energy-saving strategy called wake hunting. Wake hunting occurs when a predator takes advantage of a disturbance in the landscape. For example, in the summer as I mow the lawn, numerous bugs fly up from their hiding places in the grasses. The barn swallows seize this opportunity to dive in and feast on a buffet that has been agitated by the machine’s wake. At the bird sit on Sunday, we wondered if the Cooper’s hawk had used the noisy wake of Canada geese leaving the lake in its attempt to hunt the mourning dove. In addition to the birds, we were entertained by a muskrat at the base of the lake. The muskrat surfaced three times and always swam towards the west. Were there three muskrats? Was the muskrat stuck in a time warp? As often happens, the bird sit ended with a few answers and more questions. The natural world is fascinating!

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