The Nuttall’s woodpecker (Picoides nuttallii) is a small black and white woodpecker native to western North America. They range from southern British Columbia down through western Oregon and California. Their range extends east to the Sierra Nevada mountains and south along the coast into Baja California. Nuttall’s woodpeckers inhabit oak woodlands, riparian woodlands, and pine-oak forests.
Nuttall’s woodpeckers are classified as a Species of Special Concern by the California Department of Fish and Wildlife. They have declined in parts of their range due to habitat loss. However, globally they are still considered to be of Least Concern by the International Union for Conservation of Nature (IUCN). Overall, Nuttall’s woodpeckers remain locally common within substantial portions of their range. But they have become less common and more patchily distributed, especially in coastal oak woodlands of central California.
Range and Population
The Nuttall’s woodpecker has a relatively limited range along the Pacific coast. Their total global population has been estimated to number 120,000 individuals. Within that range, they seem to occur in locally abundant clusters. But they can be absent from apparently suitable habitat nearby. This patchy distribution may be related to their strong site fidelity, complex habitat requirements, and poor dispersal abilities.
Nuttall’s woodpeckers do not undertake long migrations. Rather they are non-migratory and resident year-round throughout their range. They have relatively small home ranges of around 40 acres during the non-breeding season. And they exhibit strong loyalty to their nesting and roosting sites. Their sedentary nature and habitat specificity likely contributes to the patchy distribution.
Habitat Loss
The decline of Nuttall’s woodpeckers in parts of their range has been attributed largely to habitat loss. Their favored oak woodland and riparian forest habitats have been substantially altered and fragmented. This habitat loss has been most extensive in the Central Valley region of California. Urbanization, agricultural conversion, river channelization, and flood control projects have greatly reduced Central Valley riparian forests. Oak woodlands have also declined, with those losses exacerbated by Sudden Oak Death in coastal areas.
Fragmentation of remaining woodlands and forests has reduced the connectivity between populations. Isolated fragments may not be large enough to support Nuttall’s woodpeckers. The reduced connectivity also limits their ability to disperse to new habitat patches after local extirpations.
Regeneration of Oaks
Another long-term threat to Nuttall’s woodpeckers is the lack of regeneration of oak and other native tree species. Nuttall’s woodpeckers depend on large old trees for nesting and roosting. But in some areas, no younger trees are available to replace aging and dying oaks and other mature trees. Lack of regeneration is likely due to habitat loss, fragmentation, deer overbrowsing, and fire suppression. Without younger trees reaching maturity, the amount of suitably aged nesting trees will eventually decline.
Adaptability
On a positive note, Nuttall’s woodpeckers have shown some adaptability to habitat alterations in oak woodlands and pine-oak forests. They are able to switch to using smaller diameter trees, dead portions of live trees, and telephone poles as nest sites where large trees are lacking. Their flexibility may allow them to persist in moderately altered or fragmented habitats. But severely degraded habitats with few suitable nest trees will still result in local extirpations.
Nuttall’s Woodpecker Identification
Nuttall’s woodpeckers are relatively easy to identify by sight and sound. Distinctive features aid in separating them from other similar woodpecker species that share their range. Being able to correctly identify them is essential for population monitoring and guiding appropriate conservation measures.
Appearance
Nuttall’s woodpeckers are small birds measuring 7 to 9 inches in length with wingspans of 13 to 16 inches. Their most conspicuous feature is the males’ bright red cap and nape. The back and wings are mostly black with white spotting. The underparts are white and the tail is black with white outer feathers. Females have an all black head without the red cap. Juveniles resemble females but have some faint red feathers mixed in on the head. Compared to other small black-and-white woodpeckers, the white back markings of Nuttall’s are distinctive.
Sound
The most recognizable vocalization of Nuttall’s woodpecker is a whinnying call typically given by males. This loud call has been described as sounding similar to a young foal whinnying. It serves as a territorial call broadcast from a high perch. Both males and females also give a sharp “pik” contact call year round. A fast rattling call is produced during the breeding season as a courtship display. Drumming against wood is low-pitched and slow.
Behavior
Nuttall’s woodpeckers can often be detected by their behavior. They move quickly over tree trunks and branches, sometimes shifting sideways around branches and lashing their tails. They excavate rectangular cavities in dead wood for nesting and roosting. Nuttall’s favor larger diameter snags and oak trees for nesting. They feed on insects gleaned from crevices in bark as well as acorns and other seeds. Their undulating flight style gives them a distinctive appearance in flight.
Nuttall’s Woodpecker Breeding
The breeding habits of Nuttall’s woodpecker allow them to produce the next generation of woodpeckers. However, specific conditions need to be met for breeding to be successful. Loss of nest sites and declining insect prey populations may be hampering breeding in some areas. Understanding limitations on successful breeding can help guide conservation actions.
Nest Sites
Nuttall’s woodpeckers nest in cavities they excavate in dead wood. The nest cavities are located between 6 to 80 feet above ground. Preferred nest trees include large diameter oaks, cottonwoods, willows and other deciduous trees. Also used are tall snags of pine, eucalyptus and telephone poles. Nest sites are a limiting factor, so preserving and recruiting suitable nest trees is crucial. installing nest boxes may help provide additional nesting opportunities.
Insects and Oak Trees
Nuttall’s woodpeckers depend heavily on insects to feed their young. So access to abundant insects during the breeding season is key. Coast live oaks support the highest densities of insects. Other important insect sources include willows, cottonwoods and dying pines. Conserving stands with a high proportion of older oak trees and snags may increase prey availability.
Acorns and other nuts from oaks and other native trees are also important for adults and young birds in fall and winter. So maintaining key mast producing trees provides essential food between insect seasons.
Threats to Breeding
Habitat loss reduces suitable nesting trees and prey availability. Nest cavities can take many years to develop, so long-term protection of existing nesting sites is crucial. Firewood cutting, removal of snags, and trimming dead branches eliminates potential nesting sites. Loss of old oaks and mast producing trees lowers insect diversity and removes essential food sources.
Expanded pesticide use reduces insect prey populations. Invasive species like European starlings compete with Nuttall’s for nest cavities. Where habitat conditions are marginal, additional stressors may tip the balance towards reproductive failure or abandonment.
Conservation Status and Protection
Although Nuttall’s woodpeckers remain fairly widely distributed within substantial portions of their historical range, habitat loss and local declines have resulted in special protections in some areas. Their relatively limited total numbers and range makes the species vulnerable to new threats. Ongoing conservation management efforts will be important for ensuring their long-term viability.
State and Global Rankings
Nuttall’s woodpecker is designated as a California “Species of Special Concern”. This status recognizes natural population declines and continuing threats that put it at risk of becoming threatened or endangered. However, globally they are ranked as a species of “Least Concern” by the IUCN Red List due to their relatively large total population size.
Federal and State Protections
Currently Nuttall’s woodpeckers have no special protective status under the U.S. Endangered Species Act or the California Endangered Species Act. They are considered nongame birds under federal and California state law. This prohibits take, possession, or commerce of birds, nests, eggs or products without a permit.
Habitat Protections
Some important woodpecker habitats receive incidental protections from laws like the U.S. Clean Water Act and state forest practice regulations. Nuttall’s likely benefit from establishment of riparian reserves and California’s Oak Woodlands Conservation Act. But most protections are generic rather than targeted specifically at woodpeckers. Stronger and more tailored habitat protections may be needed in areas where populations are declining.
Population Monitoring
Better population data helps gauge habitat protection needs. The Breeding Bird Survey monitors woodpecker populations, but coverage is limited. Expanding surveys through citizen science programs could improve trend monitoring. Nest box programs also aid research on nest site competition, reproduction and limiting factors. Banding studies help reveal dispersal patterns and habitat connectivity.
Actions to Help Nuttall’s Woodpeckers
Many groups and individuals can take actions to promote Nuttall’s woodpecker conservation. From land managers to woodlot owners to birdwatchers, various activities can contribute to preserving populations. Some helpful steps are outlined below.
Protect oak woodlands
Promote oak protection and regeneration on both private and public lands through easements, incentives and forest management practices. Prevent removal of large old oak trees that provide essential nesting and feeding habitat.
Retain snags
Leave dead, dying and decaying trees whenever it is safe to do so. Tall snags are especially valuable. Consider girdling trees or using artificial cavities to create future snag habitat.
Limit pesticides
Reduce broad spectrum pesticide use, especially neonicotinoids, to help maintain insect prey populations. Use integrated pest management practices instead.
Plant native vegetation
Encourage use of native oak trees, shrubs and grasslands in landscaping. Native plants support higher insect diversity for foraging birds. Provide berry producing shrubs for winter food.
Reduce parasitism
Remove European starling nests from cavities to prevent them from displacing woodpeckers. Control brown-headed cowbird populations to limit parasitism of woodpecker nests.
Join monitoring programs
Volunteer to monitor woodpecker populations through nest box projects or surveys. Share sightings and data with online databases like eBird.
Spread awareness
Educate others about the ecological importance of snags and native oak habitats. Promote awareness of woodpeckers and their fascinating natural history.
Conclusion
In summary, Nuttall’s woodpeckers remain fairly common locally but have declined regionally with habitat loss. Their limited range and dependence on old oaks and snags makes them vulnerable to a variety of threats. While not currently endangered, active conservation measures are needed to maintain viable populations. Protection and restoration of oak woodlands and riparian forests is most critical. Engaging the public through outreach, citizen science and voluntary actions can also significantly contribute to their conservation. With appropriate habitat management and engagement of landowners, the unique and important Nuttall’s woodpecker will hopefully continue brightening oak woodlands with its presence.