Unbelievably, these photos were taken within three weeks of each other, in which time yellow warblers grow from newly laid eggs to fledglings ready to leave the nest. The eggs in the left photo have chicks developing inside them that will hatch in ten days, featherless, blind, and helpless. Six days after that in the right photo the chicks are virtually unrecognizable. Fully feathered, eight times the size, and aware of their surroundings. Such a short period of development decreases the time that the helpless chicks are vulnerable to nest predators, but the risk still remains high. Around 70% of yellow warbler nests in Illinois are depredated before the chicks ever get the chance to leave the nest. However, adult vigilance around the nest can drastically improve these odds, and by using alarm calls to warn each other of nearby threats, warblers can more effectively defend the nest. These behaviors are what my research delves into. A happy ending awaited these chicks, as they successfully left the nest two days later. Their parents will watch over them the next few weeks, as the chicks face new predators and challenges. Out of the pan and into the fire, as they say!
