I saw a woodpecker flying into a hole in one of these dead trees. When trees die, they can remain standing for ten years or more and these dead trees are called snags. Woodpeckers and other animals use snags to make nesting sites (woodpeckers don’t nest in living trees).
Depending on the woodpecker species, they create nesting cavities at different heights above the ground. Woodpeckers breed in the spring with a short incubation period – around two weeks – although it can differ depending on the species. It’s common for woodpeckers to have 2 broods per year and some species may have 3 broods. Woodpeckers create new nesting sites every year and their old cavities are used by other hole-nesting species such as squirrels, owls and starlings. Woodpeckers nesting in snags can help keep wooded areas free of insect infestations.
Dead trees (snags) don’t look attractive and people often cut them down in their yards or woods. But if a dead tree doesn’t pose a safety hazard and it's not touching your house, it’s best to preserve it as a wildlife habitat.
Besides nesting in snags, woodpeckers also nest in human - made structures, such as wooden fence posts, utility poles, and buildings. So you still might find woodpeckers in areas that don’t have many trees.
photo from flickr creative commons