Tree swallows back, Henne

Early spring is all about firsts, and at the Henne Preserve that, of course, started with the arrival of the first Great Blue Herons last week. But long experience has taught me that when the herons return to reoccupy the rookery, they'll soon be joined by Tree Swallows. These aerial ballet artists are among the first songbirds to migrant north, and they're able to be the proverbial early birds because they can switch their diet from their typical insect prey to a menu consisting of seeds, berries, and other plant parts when cooler weather makes bugs scarce. This is a definite advantage during our always changeable March and April days, and it allows the swallows to eat well enough to have the strength to claim the best tree holes long before any competitors for such scarce real estate come back to the neighborhood house-hunting.