By John Hughes

Seeking Pygmy Nuthatch? If you are fortunate enough to have a mature stand of Ponderosa Pine trees nearby or know where a good stand exists, then you are sure to find Pygmy Nuthatch. The Pygmy Nuthatch is considered one of the best indicator species for the overall health of bird communities in a Ponderosa Pine forest. Their numbers are directly correlated with snag and foliage density within the forest; interestingly, their numbers are inversely correlated with trunk volume implying they need heterogeneous stands of older well-spaced trees mixed with younger trees of intermediate ages.

The Pygmy Nuthatch, Sitta pygmaea, is the smallest of our three species of Nuthatch. It measures 4.25” long with a wingspan of 7.75”. They are short-tailed, large-headed and long-billed. Males, females, and immatures are similar in appearance. Their crown is gray-brown with a dark eye-line marking the edge of the cap. The face is buff colored to buffy white. The breast and undertail coverts are buff, while the sides and back are bluish gray. Wing feathers and tail feathers are a darker bluish gray with the edges of the primaries white. Distinctive among the nuthatches, is their loud piping calls and constant chattering as they forage in the upper branches of Ponderosa Pines. As a matter of fact, you are as likely to hear them first as you are to observe them.

Pygmy Nuthatches feed almost exclusively in pine trees where they explore the whole tree for food. They travel and feed in loud, frenetic flocks crisscrossing the trunk to cover the tops, bottoms, and tips of branches using their bill to probe under and flake away bark in search of insects. They also glean insects from needle clusters and pine cones. For the most part, they seek out static prey, but on occasion, will hawk an insect. Pygmy Nuthatches consume beetles, ants, wasps, true bugs, and caterpillars. They also eat pine seeds. Unlike woodpeckers and creepers that use their tail to brace themselves on a tree trunk, nuthatches place one foot in front of the other using one foot to cling to the bark while the other foot provides the brace. This enables them to move up and down the tree trunk in search of food items. In winter they will feed in large flocks of related individuals and mixed species flocks.

This species is one of only a few cooperatively breeding passerines in North America. Almost half of all breeding pairs have one to three helpers to aid in the reproductive effort. The helpers are male progeny or relatives that usually stay with the adults and help for one year. Pygmy Nuthatches either excavate their own nesting cavity or use abandoned woodpecker cavities. Dead snags on living trees or dead trees are necessary for excavation sites. The male and female pair shares excavation of the nest site equally. Sometimes the helpers will do some of the excavation. A nest cup is built of bark shreds, fine moss, plant down, fur, and other soft fibrous materials often including feathers. Eggs are laid in early to late May, incubation occurring between mid to late May, and hatchlings between mid May to the middle of June. The average clutch size is seven eggs. One egg is laid each morning with incubation delayed until the last egg has been laid. The incubation period in Montana is 14.5-15 days. Females incubate the eggs but males and helpers roost overnight in the nest cavity. Males bring food to the female during incubation and help feed the young during development. Breeding pairs with helpers don’t feed their young with greater frequency than pairs without helpers, but the helpers cut the high cost of feeding the young by decreasing the number of feeding forays the parents have to make. Breeding pairs with helpers successfully fledge more offspring than pairs without helpers and nest failure occurs more often in pairs without helpers.

Pygmy Nuthatches are one of our year round residents that have adapted to our often harsh winters. They are capable of controlled hypothermia and will communally roost in stacks of six, eight, and ten in protective roost sites. While they are extremely well adapted to their environment, the health of their populations is directly tied to healthy Ponderosa Pine forest. Degradation of their habitat is the number one concern. Idaho, Wyoming, and Colorado list the Pygmy Nuthatch as a species of special concern based on its status as an indicator species for the health of Ponderosa Pine forests. Snag management and retention are important factors to consider in helping preserve this species. Observing Pygmy Nuthatches is just plain fun – I hope you’ll take some time to seek them out.