Violet-green Swallows begin nesting process

The Violet-green Swallow pair is back, and is moving in little-by-little. On April 7 they were both inside, presumably discussing the placement of furniture. Two days later the female was in, watching a black beetle scurrying around. I assume she had brought it in herself, and had released it to find and consume any lurking parasites or their eggs. It had been quite a few years since I last observed such behavior in a different pair in a different location.