Conservation and Management

The Northern Flicker is not listed as a species of concern by the federal governments in Canada or the United States. BirdLife International recognizes the Northern Flicker as three distinct species, Yellow-shafted Flicker (Colaptes auratus), Red-shafted Flicker (Colaptes cafer), and Guatemalan Flicker (Colaptes mexicanoides), but all of these taxa are ranked as species of Least Concern (292 BirdLife International (2023). IUCN Red List for birds. Close ). The Northern Flicker is widespread and common across much of North America (see Population Status).

Humans alter the environment in ways that may be both detrimental and beneficial for Northern Flicker populations. Although the Northern Flicker remains common, the long-term declines within some North American populations are cause for concern. There have been no rigorous, focused studies to identify the cause of declines but there are 4 common hypotheses: (1) competition for nest cavities from the introduced European Starling (Sturnus vulgaris), (2) declining availability of suitable nest-cavity substrate (snags, dead limbs, and live trees with heart rot), (3) the loss of aspen habitat as a result of fire suppression, and (4) pesticide application on golf courses, agricultural fields, and suburban lawns.

Habitat Loss and Degradation

The removal of snags during forestry operations and urban development seems to reduce habitat suitability by removing nest sites (293 Blewett, C. M., and J. M. Marzluff (2005). Effects of urban sprawl on snags and the abundance and productivity of cavity-nesting birds. Condor 107(3):678–693. Close ). On the other hand, flickers favor open landscapes and relatively open forest structure, so disturbances such as fire, logging, or insect outbreaks that open up the forest floor and increase the abundance of standing dead wood are positively associated with local population increases. Northern Flicker is among the species with increasing population density in an increasingly fragmented boreal forest region (294 Mahon, C. L., G. L. Holloway, E. M. Bayne, and J. D. Toms (2019). Additive and interactive cumulative effects on boreal landbirds: winners and losers in a multi-stressor landscape. Ecological Applications 29:e01895. Close ; see also Population Regulation). Fire suppression within grassland-aspen habitats in the western United States may lead to conifer encroachment and ecological succession which reduces habitat suitability for the Northern Flicker (295 Sadoti, G. (2009). Breeding ecology of two cavity-excavators in aspen forests of the northeastern Great Basin: Testing for adaptive selection of nest-sites at multiple scales. M.S. thesis, University of Idaho, Moscow, ID, USA. Close ).

Effects of Invasive Species

A decline in Northern Flicker populations in the southeastern and central United States and Canada has been attributed to competition with European Starling (296 Robbins, C. S., D. Bystrack, and P. H. Geissler (1986). The Breeding Bird Survey: its first fifteen years, 1965–1979. U.S. Fish and Wildlife Service Resource Publication 157. Close , 297 Erskine, A. J. (1992). Atlas of Breeding Birds of the Maritime Provinces. Nova Scotia Museum, Halifax, NS, Canada. Close ), but Koenig (298 Koenig, W. D. (2003). European Starlings and their effect on native cavity-nesting birds. Conservation Biology 17:1134–1140. Close ) failed to find negative correlations between starling and flicker populations using Christmas Bird Count data. However, such survey data may be rather coarse and there are many reports of starlings usurping nest cavities from Northern Flickers (299 Shelly, L. O. (1935). Flickers attacked by starlings. Auk 52:93. Close , 9 Bent, A. C. (1939). Life histories of North American woodpeckers. United States National Museum Bulletin 174, Smithsonian Institution, Washington, DC, USA. Close , 300 Howell, A. B. (1943). Starlings and woodpeckers. Auk 60:90–91. Close , 301 Bent, A. C. (1950). Life Histories of North American Wagtails, Shrikes, Vireos, and Their Allies. United States National Museum Bulletin 197:182–214. Close , 131 Brackbill, H. (1957). Observations on a wintering flicker. Bird-Banding 28:40–41. Close , 206 Fisher, R. J., and K. L. Wiebe (2006). Nest site attributes and temporal patterns of northern flicker nest loss: effects of predation and competition. Oecologia 147(4):744–753. Close ). In some populations, the rate of nest loss to starlings appears to be high. For example, 40% of flicker nests were lost to starlings in Miami, Florida (302 Diamond, J. M., and M. S. Ross (2020). Overlap in reproductive phenology increases the likelihood of cavity nest usurpation by invasive species in a tropical city. Condor: Ornithological Applications 122:1–22. Close ) and 68% of flickers on a study site in Ohio lost their nests to starlings although nest boxes were experimentally placed near the cavities to provide accommodation for starlings (303 Ingold, D. J. (1998). The influence of Starlings on Flicker reproduction when both naturally excavated cavities and artificial nest boxes are available. Wilson Bulletin 110(2):218–225. Close ). The delayed nesting of flickers caused by competition with starlings reduces reproductive output (304 Ingold, D. J. (1996). Delayed nesting decreases reproductive success in Northern Flickers: implications for competition with European Starlings. Journal of Field Ornithology 67(2):321–326. Close ). The intensity with which a flicker defends its nest is related to past experience with starlings, but often defense is unsuccessful (194 Wiebe, K. L. (2004). Innate and learned components of defence by flickers against a novel nest competitor, the European Starling. Ethology 110(10):779–791. Close ). The impact of nest usurpation at the population level may depend on whether a flicker can renest after being displaced, but the seasonal decline in clutch size means there is still a reproductive cost to eviction (254 Wiebe, K. L. (2003). Delayed timing as a strategy to avoid nest-site competition: testing a model using data from starlings and flickers. Oikos 100(2):291–298. Close ). More study is needed on how various rates of nest usurpation in different flicker populations translate to reduced productivity at the population level.

Shooting and Trapping

Historically, often taken by gunners. Stone (147 Stone, W. (1937). Bird Studies at Old Cape May: an Ornithology of Coastal New Jersey. Delaware Valley Ornithology Club, Philadelphia, PA, USA. Close ) described the slaughter at Cape May, New Jersey: “Not many years ago Flickers were lawful game in New Jersey, and the Cape May gunners, well versed in the character and time of these flights [fall migration], made regular preparation for them. Poles or fence rails were fastened to the tops of the low pines and cedars at the Point so they projected upward above the topmost branches and formed resting places that the Flickers could not resist. The result was that the tired birds, stopping for a few moments on their wild flight, lined the poles so that at any moment six or more were clinging to the perches and a gunner concealed at the base of the tree ‘raked' them off with the greatest ease...two gunners secured six peach baskets full of flickers on a single morning and piles of dead birds as high as a man's knees were frequent sights....” Such slaughter is, of course, a thing of the past.

Pesticides and Other Contaminants/Toxics

Anecdotal deaths from pesticides are reported (272 Fleischli, M. A., J. C. Franson, N. J. Thomas, D. L. Finley, and W. Riley Jr. (2004). Avian mortality events in the united states caused by anticholinesterase pesticides: A retrospective summary of National Wildlife Health Center records from 1980 to 2000. Archives of Environmental Contamination and Toxicology 46(4):542–550. Close ), but there is presently no evidence that populations are particularly at risk from chemicals.

Collisions with Stationary/Moving Structures or Objects

Collisions with vehicles, windows, wind turbines, and communications towers are known to occur. Northern Flicker was among the 25 most common bird species to be struck by wind turbines in some parts of North America, but not in others (270 Allison, T. D., and R. Butryn (2019). A summary of bird fatality data in a nationwide database. American Wind Wildlife Institute Technical Report. Close ). It can also fall victim to colliding with windows (271 Schneider, R. M., C. M. Barton, K. W. Zirkle, C. F. Greene, and K. B. Newman (2018). Year-round monitoring reveals prevalence of fatal bird-window collisions at the Virginia Tech Corporate Research Center. PeerJ 6:e4562. Close ) and communications towers (148 Johnston, D. W., and T. P. Haines (1957). Analysis of mass bird mortality in October 1954. Auk 74:447–458. Close ). It was listed among those species with higher than average risk for collisions with buildings (305 Loss, S. R., T. Will, S. S. Loss, and P. P. Marra (2014). Bird-building collisions in the United States: Estimates of annual mortality and species vulnerability. Condor 116:8–23. Close ). Study is needed on the population-scale impacts of collision-related mortality.

Other Human/Research Impacts

Because the Northern Flicker commonly nests in or near human habitation it seems to be able to adapt to many disturbances. It is tolerant of human activity in the vicinity of a nest site; at least once a parent is committed to incubation or feeding nestlings. During sanctioned research activities, Northern Flickers were trapped in nest cavities for banding, and after these brief nest visits by humans, adults returned to the nest and continued regular parental care (KLW, WSM).

Conservation Measures and Habitat Management

Conservation of the Northern Flicker is important because this is the primary predator on ants in woodland habitats and because it acts as a keystone species by excavating a large percentage of the nest cavities used by numerous secondary cavity-nesting species (5 Martin, K., K. E. H. Aitken, and K. L. Wiebe (2004). Nest sites and nest webs for cavity-nesting communities in interior British Columbia, Canada: Nest characteristics and niche partitioning. Condor 106(1):5–19. Close ). The loss or reduction in flicker numbers would likely have a large impact on the biodiversity of vertebrates in most woodland ecosystems in North America. Because it has not been recognized as a threatened species, few conservation measures have been proposed and no specific actions appear to have been taken. Especially in areas with possible population declines (e.g., eastern North America), basic research is needed to determine whether nest-substrate availability limits populations. More extensive experiments involving manipulation of snag density, similar to studies of Scott and Oldemeyer (277 Scott, V. E., and J. L. Oldemeyer (1983). Cavity-nesting bird requirements and responses to snag cutting in ponderosa pine. In Snag Habitat Management: Proceedings of the Symposium (J. W. Davis, G. A. Goodwin, and R. A. Ockenfels, Editors), U.S. Forest Service Geneneral Technical Reports RM-99. pp. 19–23. Close ), would be useful.

Several factors may contribute to a reduction in nest-cavity substrate: expansion of suburbs; policies for removing snags, dead limbs, and diseased trees from urban and suburban areas (306 Tomasevic, J. A., and J. M. Marzluff (2017). Cavity nesting birds along an urban-wildland gradient: Is human facilitation structuring the bird community? Urban Ecosystem 20:435–448. Close ); and inadequate or unenforced snag and dead-limb maintenance policies in forests. Effective management policies must consider the dynamic-equilibrium of the snags and dead limbs that comprise the standing crop (307 Sedgwick, J. A., and F. L. Knopf (1992). Cavity turnover and equilibrium cavity densities in a cottonwood bottomland. Journal of Wildlife Management 56:477–484. Close ) and a range of decay classes of trees needs to be maintained to ensure a continual turn-over and a supply of fresh cavities (308 Edworthy, A., K. L. Wiebe, and K. Martin (2012). Survival analysis of a critical resource for cavity-nesting communities: patterns of tree cavity longevity. Ecological Applications 22:1733–1742. Close , 197 Cockle, K. L., K. L. Wiebe, M. K. Trzinski, A. B. Edworthy, and K. Martin (2019). Lifetime productivity of tree cavities used by cavity-nesting animals in temperate and subtropical forests. Ecological Applications 29(5):e01916. Close ). In forested areas, snags should be left in harvested and burned areas (278 Saab, V. A., R. E. Russell, and J. G. Dudley (2007). Nest densities of cavity-nesting birds in relation to postfire salvage logging and time since wildfire. Condor 109:97–108. Close , 232 Wiebe, K. L. (2014). Responses of cavity nesting birds to fire: testing a general model with data from the northern flicker. Ecology 95:2537–2547. Close ). Thomas et al. (309 Thomas, J. W., R. G. Anderson, C. Maser, and E. L. Bull (1979). Snags. In Wildlife Habitats in Managed Forests: the Blue Mountains of Oregon and Washington (J. W. Thomas, Editors). U.S. Department of Agriculture Forest Service Handbook no. 553, Washington, DC, USA. pp. 60–77. Close ) estimated that 93 snags/100 ha would result in flicker populations reaching 100% of their potential density in several western woodland communities. The retention of aspen trees in blocks of harvested boreal forest was linked to increased populations of flickers after harvest (199 Cooke, H. A., and S. J. Hannon (2011). Do aggregated harvests with structural retention conserve the cavity web of old upland forest in the boreal plains? Forest Ecology and Management 261:662–674. Close ). Flickers apparently ignored artificial snags placed in clearcuts (310 Petit, D. R., K. E. Petit, T. C. Grubb, and L. J. Reichhardt (1985). Habitat and snag selection by woodpeckers in a clear-cut: analysis using artificial snags. Wilson Bulletin 97(4):525–533. Close ).

In other ecosystems it may be important to allow natural disturbance regimes that keep the landscape structure open. For example, restoring open oak habitats in Oregon and California by removing encroaching conifers lead to an increase in flickers (311 Stephens, J. L., and C. R. Gillespie (2021). Restoration treatments reduce threats to oak ecosystems and provide immediate subtle benefits for oak-associated birds. Restoration Ecology 29(1) e13298. Close ). The loss of trembling aspen (Populus tremuloides) woodland, a favorite nesting substrate of flickers, as a result of aspen die-off or fire suppression often results in conifer encroachment. Maintaining natural disturbance levels in such ecosystems is important as flickers avoided dense conifer areas and settled within aspen/grassland edges (295 Sadoti, G. (2009). Breeding ecology of two cavity-excavators in aspen forests of the northeastern Great Basin: Testing for adaptive selection of nest-sites at multiple scales. M.S. thesis, University of Idaho, Moscow, ID, USA. Close ).

As a result of numerous observations of the introduced European Starlingevicting flickers from nests (see Effects of Invasive Species) some have recommended placing nest boxes to reduce competition over cavities. In an experiment, Ingold (303 Ingold, D. J. (1998). The influence of Starlings on Flicker reproduction when both naturally excavated cavities and artificial nest boxes are available. Wilson Bulletin 110(2):218–225. Close ) placed nestboxes beside flicker cavities, but 68% of flickers still lost their nests to starlings, despite available boxes.

Effectiveness of Measures

Because it is not recognized as a threatened species, no conservation measures have been officially enacted or studied.