A strong spring storm blasted through Colorado last Friday and Saturday, bringing lots of much-need moisture in the form of rain and snow. In some areas the snow piled up by the foot, especially in the elevations where Mountain and Western Bluebirds were already on territories. In April storms like this, the early-arriving bluebirds retreat back down to the plains to ride out the weather. Birders visiting Chatfield Reservoir SW of Denver on Saturday reported seeing thousands of bluebirds, so when the weather cleared out on Sunday I went down to check it out.
Sadly, the storm had been too much for some bluebirds, and I found some where they had perished looking for shelter in the lee of buildings or at the base of vegetation. But there were lots of bluebirds still around, and I'd estimate I saw at least 1000 throughout the park on Sunday. Most were Mountain Bluebirds but perhaps 1 in 3 were Westerns. Eventually, I found an Eastern Bluebird, too. At that point all three bluebird species were visible from the same place- the first time I've ever been able to claim that! In contrast to the soggy, miserable birds that I saw in the rain and snow the day before, these birds were dry, fluffy, and gorging on worms creeping along the soggy ground and torpid insects melting out of the snow. So like lots of things in the natural world, the storm wasn't really all good or bad- while it cut down some birds it provided a feeding opportunity for survivors.
By the afternoon the snow was fast receding and so were the bluebirds- many were heard or seen flying north and west to head back up towards their breeding grounds. Another storm (probably mostly rain this time) is predicted for the weekend so we'll see what drops out in that one!
Spring Migration 2017, Part 2
2 months ago