The Red-cockaded Woodpecker (Picoides borealis) is a cooperatively breeding species that typically uses a single cavity for nesting (Ligon 1970, Walters et al. 1988). A single tree, or aggregation of cavity trees, termed the cluster, is inhabited by a group of woodpeckers that includes a single breeding pair and up to several helpers, which are typically male offspring of previous breeding seasons (Ligon 1970, Lennartz et al. 1987). Each group of Red-cockaded Woodpeckers usually produces one nest per breeding season, but will often nest again during the same breeding season if the first nest fails. Double clutching and double brooding (where both nests are successful) are known to occur in Red-cockaded Woodpeckers in the southern and northern portion of the species' range (LaBranche et al. 1994, Franzreb 1997, Phillips et al. 1998).
Conner, Richard N.; Saenz, Daniel; and McCormick, James R., "An unusually large number of eggs laid by a breeding red-cockaded woodpecker female" (2001). Faculty Publications. 160.