Bird's-Nest Life Cycle

Day 40: Bird's-Nest fungi such as these specimens of Nidula niveotomentosa grow on rotting wood and propagate by means of spores contained in tiny lentil-like structures known as peridioles. Each "nest" is only about the size of a pencil eraser. The "eggs" of this species measure 0.5-1.0 mm and are protected by a gelatinous substance. When this fungus first emerges, the "nest" is covered by a dome which bursts as it matures, revealing the peridioles in the gel. They are then washed from their "nests" as the cups fill with rain. It is not uncommon to find lines of bird's-nests following cracks in old wood or colonies confined to low areas where the peridioles have come to rest. In this photo, you can see one unopened bird's-nest, one in which the peridioles are still suspended in the gel, two which are fully open, and several faded, grey ones from last year. Note also the peridioles on the rims of the cups and one (far right) resting on bare wood.