Northern Flicker Colaptes auratus Scientific name definitions

Karen L. Wiebe and William S. Moore
Version: 2.0 — Published July 7, 2023

Demography and Populations


The Northern Flicker has a relatively "fast" life history compared to most other woodpeckers and other avian species of similar body size (249, 250). As detailed below, this entails breeding in the first year of life, large clutches, and relatively short lifespan. The breeding population for the United States and Canada is estimated at 11,000,000 individuals, and the global population is estimated at 12,000,000 (251).

Measures of Breeding Activity

Age at First Breeding

Both sexes can breed when they are about 1 year of age (Formative Plumage), and it seems that most attempt to do so. Of 1,675 breeding attempts recorded at Riske Creek in central British Columbia over a timespan of 18 years, 39% involved a yearling female and 37% a yearling male (252 ,249).

Intervals Between Breeding

Mark-recapture analysis suggests that the Northern Flicker breeds annually (249).

Clutch Size and Number of Clutches per Season

The Northern Flickeris among those species of woodpeckers in which clutch size increases with latitude (253). Various estimates for clutch sizes at different geographical locations are in Eggs. At Riske Creek, the size of first clutches: 7.99 ± 1.3 SD (n = 1,579) and for second (replacement) clutches: 6.83 ± 1.1 SD (n = 266); for all clutches pooled: 7.81 ± 1.4 SD (range 2‒13, n = 1,872) (KLW) . Only one clutch (brood) is reared but a female may replace clutches that are destroyed if there is still enough time in the breeding season to rear offspring. The probability of renesting according to date for females at Riske Creek is plotted in (254). Up to 2 replacement clutches for a female have been observed at Riske Creek. Clutch size declines significantly with laying date even within first clutches. The number of eggs fell by 0.056 eggs/day for yearling females and by 0.062 eggs/day for older females (254).

Clutch size also varies with the age of parents. As a female aged, clutch size increased from the first year of life (yearling females lay about 7.5 eggs) to the second year (about 8.5 eggs) but did not change significantly thereafter whereas clutch size increased with the age of the male partner, up to age 5 (252). Thus, females seem to adjust the number of offspring according to the quality and parental effort of the male.

Annual and Lifetime Reproductive Success

At Riske Creek, 71% of 1023 nests survived to the hatching stage. The other nests were either depredated (16%), evicted by European Starling (Sturnus vulgaris) (5.4%), or the nest tree blew down (0.6%). A handful of nests were abandoned for unknown cause (see 254, 206), possibly attributable to a predation attempt or a result of competition with other species for the nest cavity. Of 1494 nests which survived to the hatchling stage at Riske Creek, 89.8% fledged at least one offspring, or when the sample of all nesting attempts is considered (n = 2,072), 69.9% of initiated nesting attempts produced at least one fledgling.

On the central plains in the United States, 78% of nests (n = 119) survived to the hatching stage, and of those nests with hatchlings, 86% of nests survived to age of nestling banding, 11–14 d after hatching (WSM). In Wisconsin, 4 of 12 nests were depredated (171), and on Nantucket Island, Massachusetts, 8 of 30 nests failed generating an overall success rate of 73% (222). In salvage-logged sites in Idaho, average nest success was about 64% (n = 293) (255). In Washington State, nest predation was higher in unburned stands (37% of 41 nests) compared to burned stands (30% of 45 nests) and overall nest survival was 41% in unburned and 80% in burned stands (214). In partly harvested woodlots in southern Ontario, apparent nest success was relatively high, at 81% (n = 69), and Mayfield success was 0.76 (256). In this latter study, nests higher above ground and in larger and healthier trees were more successful. On a study site in Idaho, nest predation rates were relatively high, with 12 of 20 nests (60%) lost, with predation by weasels implicated as a main cause (257).

Nest loss rate increased during the breeding season in Washington State (214) whereas in central British Columbia, the loss rate reached a peak in the mid-breeding season (206).

At Riske Creek, among nests surviving to hatching (n = 1,505), the average brood size just after hatching averaged 0.90 smaller than the clutch size (KLW) because some eggs fail to hatch. Most unhatched eggs appeared infertile, with no embryo or blood spots when cracked open (KLW). Among these nests, the average number of fledglings produced was 5.46 ± 2.4 SD (KLW) which was about one nestling less than at hatching, suggesting that on average one nestling is lost during the brood-rearing period (e.g., through starvation). In Nebraska and Wyoming, mean brood size (10–17 d posthatch) varied from 5.86 to 7.22, or about one less than clutch size (234).

Number of Broods Normally Reared per Season

Apparently single-brooded, but this needs confirmation in other color-banded populations.

Life Span and Survivorship

Survivorship appears lower, on average, than that of many other woodpecker species (250). Based on banding and recovery data conducted during 18 breeding seasons at Riske Creek in central British Columbia, the oldest male was 10 years old (1 of 1,564 individuals) and the three oldest females were 9 years old (3 of 1,525 individuals) (252). The maximum longevity reported from U.S. Geological Survey Bird Banding Lab data is 9 yr, 2 mo (258).

Annual survivorship of adults (> 1 year old, ages and sexes pooled) was 0.43 (95% CI: 0.38–0.48) (249). The estimated apparent survival from the Monitoring Avian Productivity and Survivorship (MAPS) program, based on standardized mist-netting efforts, was 0.47 although this should be viewed with caution owing to the small sample size of recoveries (259). Survival at Riske Creek depended on the North Atlantic Oscillation, a large-scale climactic pattern which might have affected conditions on the wintering grounds or during migration, but survival did not depend on sex or hybrid phenotype (51).

The daily survival estimate for juveniles based on following 29 fledglings fitted with radio-transmitters for 22 days immediately post-fledging was 0.996 ± 0.004, which projects to 0.64 survival at the end of 2 months (248). There are no good survival estimates for the first year of life due to the high natal dispersal and lack of band recoveries.

Disease and Body Parasites

Body Parasites

Endoparasitic coccidian protozoans in the genus Isospora were isolated from the intestinal contents of a Northern Flicker during necropsy (260), but their prevalence in wild populations is unknown. A nesting female flicker was heavily infested with coelomic nematodes (Diplotriaena) and acanthocephalid worms in the intestine (261). Avian malaria, a blood parasite, has also been described in the Northern Flicker (262).

In terms of ectoparasites, Northern Flickers may have feather mites including Stenopteronyssus proctorae (263). They also harbor several species of chewing lice, including Menacanthus pici, Penenirmus jungens, and Picicola porisma, with prevalence ranging from 38–85% and intensities ranging from 0–1,359 lice per bird depending on species of louse (264, 265). The Northern Flicker was among the bird species recorded as having ticks although the prevalence and number was not reported (266). Both adults and nestlings may host blood sucking flies in the family Hippoboscidae which sometimes emerge from the feathers during banding (KLW); the species Ornithoica vicina was identified on Northern Flickers in Wisconsin at a prevalence of 2.5% of 197 individuals (267).

At Riske Creek in British Columbia, nearly all nestlings become infested with the ectoparasite fly Carnus hemapterus which congregates in the skin folds and wing pits of the developing young. Intensity of parasites increases rapidly during the first week of the nestling period, reaching an average intensity of 15.1 ± 8.3 SD flies per nestling in the second week (268). Experimental fumigation of nests to rid them of Carnus flies resulted in higher fledging masses; however, freshly excavated nests did not offer health benefits because parasite prevalence was no different from that in reused cavities (268). Blowflies (Protocalliphora lata) are detected in a relatively small percentage of nests (< 5% annually) (KLW). More studies are needed to quantify the prevalence and reproductive consequences of various endoparasites and ectoparasites.


West Nile Virus was reported from a Northern Flicker in California (269).

Causes of Mortality


Rarely (e.g., in about 1% of nests), nestlings may die as a result of the cavity being flooded by rain (KLW).


About 18–20% of nests annually were lost to predators (primarily red squirrel [Tamiasciurus hudsonicus]) at Riske Creek, British Columbia (206). An average of 9% of radio-tagged Northern Flicker adults was killed while foraging by avian predators during the 3 months they were monitored during the breeding season (156). For a list of nest of predators, see Behavior: Predation.


West Nile Virus has been reported from a Northern Flicker in California (269), but no information on population-level impacts.

Direct Human Impacts

The 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). It can also fall victim to colliding with windows (271) and communications towers (148). Study is needed on the population-scale impacts of collision-related mortality.

Anecdotal deaths from pesticides are reported (272), but there is presently no evidence that populations are particularly at risk from chemicals.

Population Spatial Metrics

Individual Distance

Information needed.

Territory Size

Defends an area around the nest tree, but does not defend a classic feeding territory probably because their main prey (ants) are not economically defendable (167). The size of the defended area around the nest tree may depend on the stage of breeding and on snag densities, but more information needed. The shortest distance between two nests at Riske Creek was 5 m (two pairs breeding in adjacent trees), and active nests 30–50 m apart were not rare (KLW). This suggests a defense radius of between 5–25 m around the cavity tree. Distances between nests are determined by agonistic behavior but also depend on snag density, so one must be cautious about inferring territory size from distances between nests. With that caveat, in riparian woodlands with many snags in western Nebraska, the average distances among nearest-neighbor nests was 103 m (range 20–241, n = 19 nests; WSM, unpublished data 1982–1984). At a New Hampshire beaver pond, 3 active nests were 16, 70, and < 70 m apart (133). In southern Ontario, pairs nesting in two adjacent territories had nests separated by an average of 253 m, averaged over 3 years (146). See also Agonistic Behavior: Territorial Behavior.

Home Range Size

Conducts its normal activities in undefended home ranges during both nonbreeding and breeding seasons. In late winter, 4 individuals in Colorado occupied home ranges of 48‒101 ha (134). Monitoring radio-tagged birds during the breeding season at Riske Creek, British Columbia revealed home ranges (95% convex polygons) of 5‒109 ha (mean 25 ha, n = 52) (155). Home ranges did not differ in size between the sexes (162). See Agonistic Behavior: Territorial Behavior.

Population Status


The Northern Flicker is widespread and common across much of North America. Using data from the North American Breeding Bird Survey (BBS) the population was estimated at 11,000,000 individuals (95% CI: 10–12 million) for the United States and Canada for 2006–2015; the global population was estimated at 12,000,000 (251). Point-count abundance data collected by breeding bird atlas projects estimated populations at 700,000 individuals in Ontario for 2001–2005 (273), 354,800 birds (95% CI: 290,900–442,900) in West Virginia (274), 187,000 birds (95% CI: 177,000–197,000) in Pennsylvania for 2004–2009 (275), and 185,000 birds (95% CI: 165,000–205,000) in Ohio for 2007–2011 (276). Generally speaking, higher abundances during the breeding season occur in forested regions of the western United States, southwestern Canada, and the Great Lakes region (see Movements and Migration). However, abundances on a continental scale do not necessarily reflect local densities within habitats; e.g., breeding Northern Flickers are abundant in woodland habitat on the Great Plains (Habitat in Breeding Range), but such woodland habitat is sparse.

Reported densities of breeding Northern Flickers include: ponderosa pine forest (Arizona), 1 individual/4 ha (mean for 3 plots before snag removal; 277); pine–fir forest (California), 1 pair/111 ha on unburned plots (mean for 5 plots; 118); burned forest plots in Idaho, 1 pair/22.5 ha (unlogged), 1 pair/38 ha (salvage logged; 278). At Riske Creek, British Columbia, average densities were about 1 pair/50 ha (over a 7,500 ha tract of grassland and patchy forest, KLW), but localized densities can be much higher in larger groves of trembling aspen (Populus tremuloides) (see 167).

Maximum winter abundances (individual birds observed/party hour) based on Christmas Bird Counts (CBC): Yellow-shafted Flicker 2.77/h, with maximum abundance along river valleys and coastal plains, below 305 m; Red-shafted Flicker 4.72/h, with maximum abundance in river valleys, but more abundant at higher elevations than Yellow-shafted Flicker (279).


Trends vary according to geographic location and time frame analyzed and are conflicting. Long-term population trends from the BBS (1966–2019) indicated a 1.2% annual decline (95% CI: –1.4, –1.0; n = 4,391 survey routes) averaged across the BBS survey region in Canada and the United States (280; Figure 8). During that time frame, significant declines occurred in 40 of 58 (70%) states and provinces, and there were no significant increases. Decreases are focused in the eastern and central United States; considering the time frame from 1993–2019, an annual decline averaging 1.59% occurred in central and eastern North America while populations in the West showed no trend (280), however, the statistical confidence of any trends was rated as "low" for all geographic regions. Thus, it is possible that yellow-shafted subspecies is declining in the south-central and southeastern regions of North America, whereas there may be no ongoing trend for red-shafted populations in the West. A more recent long-term survey in Alaska indicated that the Northern Flicker (red-shafted group) was increasing there (281). Christmas Bird Count (CBC) data from Nebraska showed a significant increase in the number of overwintering Northern Flickers during the period 1992–2020 (282), consistent with CBC data for Northern Flickers overwintering in the Great Plains (283).

Population Regulation

Because Northern Flickers require an appropriate substrate for nesting (a dead or declining tree of sufficient girth), the density of some populations may be limited by the availability and spacing of suitable nest sites (124, 232). Carefully designed experiments are needed to determine whether cavity abundance is limiting for a population (284). The density of Northern Flickers decreased on an experimental plot where ponderosa pine was harvested and snags were removed, but increased on a harvested plot where snags were left and on a control plot that was not harvested (277). Similarly, density decreased to half its pretreatment level when snags were removed from a burned pine–fir site in California, and density was at least 5 times as high in the burned forest as at any unburned site (118).

Because the Northern Flicker is associated with open habitats and open woodlands, disturbances (either natural or human caused) that open up a dense forest canopy have been linked to population increases. For example, numbers increased after a pine beetle outbreak and the associated selective logging at Riske Creek, British Columbia (285, 286). In the Okanagan region of British Columbia, densities increased during 3–8 years after a wildfire that opened up the forest canopy (287). At Riske Creek, breeding densities increased 1.77-fold in the short term (1–3 years) after wildfires but declined to baseline levels once burnt snags began to fall (216). In general, populations show little response to forest insect outbreaks compared to other woodpeckers because their main prey is ground-dwelling ants. Based on a variety of study areas in western Canada and the United States, density showed no consistent trend with outbreaks of mountain pine beetle although they did increase on plots that were salvage-logged (288, 289). Daily nest survival rates also did not vary according to pine beetle outbreak (290), and densities did not respond to gypsy moth outbreaks in the short term (291). Thus, whereas the availability of snags seems to have a clear role in determining population densities, studies are needed to test whether the availability of food (ants and other terrestrial insects) ever regulates Northern Flicker population sizes.

Competition with other cavity-nesting species may also influence population density. Competition with the European Starling is often evoked as an explanation for dwindling numbers of the Northern Flicker (see Management and Effects of Human Activity).

Recommended Citation

Wiebe, K. L. and W. S. Moore (2023). Northern Flicker (Colaptes auratus), version 2.0. In Birds of the World (P. G. Rodewald, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.norfli.02