Picman calculated that the meadowlarks were responsible for more than 20 percent of all predation on songbird eggs in his Ottawa study area. Since the egg contents were relatively untouched, that is, not eaten, by the meadowlarks, Picman believes that the egg-pecking is undertaken to reduce competition for food resources in the area. Just like the wrens. According to Terry Grubb and Roy Lopez of the Rocky Mountain Forest and Range Experiment Station in Flagstaff, Arizona, writing in the September 1997 issue of The Wilson Bulletin, bald eagles are a lot more clever than I have given them credit for being. Northern Arizona winters can be quite variable, sometimes a tad chilly with occasional heavy snow cover and extreme cold, and at other times, dry and mild with no snow cover at all.
Lakes then can freeze over and thaw out several times in one winter.
One adult landed near the shore and began intermittently jumping up and down on the ice for about a minute. Breaking the ice without falling in, the bird created a hole about a half-meter in diameter. Moving onto an unbroken edge and using its foot, it actually removed a chunk of ice from the hole. Then it moved about two meters away to stand among some emergent reeds. After a couple of minutes, the eagle returned to the hole, grabbed a 10-centimeter long fish, and flew back to the reeds to consume it.