The Nidulariaceae ('nidulus' - small nest) are a family of fungi in the order Nidulariales. Commonly known as the bird's nest fungi, their fruiting bodies resemble tiny egg-filled birds' nests. As they are saprobic, feeding on decomposing organic matter, they are often seen growing on decaying wood and in soils enriched with wood chips or bark mulch; they have a widespread distribution in most ecological regions.