19 October 2010
Tillie Creek Campground
Kern County, California
A Loggerhead Shrike catches my eye as it arrows low across my path toward a small live oak. It lands low at a main fork in the trunk and quickly leans in and seizes something. But before I can identify the shrike’s prize, I’m distracted by the quick arrival of a shiny male Anna’s Hummingbird, which starts diving at the shrike. The shrike quickly takes flight, with the belligerent hummer hard behind, and goes to the top of a large blue oak about 100 feet away, where it perches and then endures a renewed bout of energetic dives from the hummer.
With each of the hummingbird’s near passes, the shrike lets out an irritated sharp, grating note. After four or five dives, the hummingbird pauses briefly, hovering beside the shrike, and then suddenly zips away in pursuit of some other enterprise.
I ponder the purpose of this attack and so many similar ones I’ve observed over the years as hummingbirds attacked an impressively diverse array of birds, dogs, deer, dragonflies—and even me! Every time I was able to determine the sex of the attacking hummingbird, it was always a male, and the flights at these more or less stationary subjects most often resembled the high looping hummingbird display flight. The hummers frequently pursue the target of their wrath quite aggressively. Now, I can understand the potential benefit of directing such attacks at a shrike, which might pose a threat to a hummingbird or its young, but that logic does not explain why a glittering male Anna’s Hummingbird would fly in hot pursuit of a panic-stricken Mourning Dove!