|Photo by: Stephen Cresswell|
Melanerpes erythrocephalus erythrocephalus L.
Melanerpes erythrocephalus caurinus Brodkorb
Red-headed woodpeckers are highly territorial and aggressive [6,49,63]. Confrontations between conspecifics and other species are common [6,42,69]. Red-headed woodpeckers usurp nests from northern flickers (Colaptes auratus) and red-bellied woodpeckers (Melanerpes carolinus) [42,45]. In turn, red-headed woodpecker nests are occasionally usurped by European starlings (Sturnus vulgaris) [42,43,45]. Despite their aggressive temperaments, red-headed woodpeckers occasionally share a nest tree with other species including red-bellied woodpeckers, northern flickers, European starlings, American kestrels (Falco sparverius), and Indiana bats (Myotis sodalis) [43,44,53,69,94].
Although solitary in winter [57,62], red-headed woodpeckers are monogamous and may remain paired for several breeding seasons . Red-headed woodpeckers are primary cavity nesters that excavate their own nest and roost cavities [80,83]. However, they also use existing holes for nesting and roosting [5,20,80]. Nesting is typically initiated from early May to mid-June, but it may begin as early as February in the Southeast [42,45,69,85]. Excavation of nest cavities begins during the second half of April, peaks in early May, and continues until the end of July [35,42]. Egg laying begins in early May and usually ends by mid-August [7,35,42,48]. Clutches contain 4 to 5 eggs on average, with 3 to 10 eggs possible [6,35,42,48,59,96]. Some pairs raise 2 broods in a season [6,42,43,44]. Clutch size is typically larger during first brood attempts than second brood attempts .
Incubation lasts 12 to 14 days [6,7,48,59,69]. Asynchronous hatching may occur if incubation begins before all eggs are laid . Nestlings are present from mid-May to late August with a peak in early to mid-June in the southern extent of the range and a mid-July peak in the northern extent [42,45]. Fledging occurs from the second week of June to the first week of September [7,35,42,45]. Nestlings fledge at approximately 24 to 30 days of age [6,7,59,69]. Pairs in Mississippi fledged 2.1 to 2.3 young/brood on average . Parents drive juveniles from the nest several weeks after fledging [7,62].
Red-headed woodpeckers generally have high nesting success. In Colorado, red-headed woodpeckers experienced 50% to100% nesting success . Average nest success was 78% throughout the United States .
Red-headed woodpecker mortality is highly variable. Winter mortality of red-headed woodpeckers in Ohio was 7% . Annual mortality of adult red-headed woodpeckers was reported as 38% in a review . Adult mortality was low in a Colorado study . Red-headed woodpeckers may succumb to exposure in winter. Both adult and juvenile red-headed woodpeckers were found dead in Illinois after heavy snowfall and severe cold. Immature red-headed woodpeckers may fare worse than adults .
The maximum life span of the red-headed woodpecker is unknown. One red-headed woodpecker was recaptured 9 years and 11 months after banding . However, most red-headed woodpeckers probably do not live more than 2 years .PREFERRED HABITAT:
Red-headed woodpeckers show a preference for mature open canopy forests with large trees, a high basal area, and little understory [14,15]. In a Texas study, 79% of red-headed woodpeckers were observed in a bottomland hardwood forest that had high crown closure in the overstory and low understory and mid-story growth. Hardwood-dominated ridges adjacent to the bottomland forest housed nearly 17% of the red-headed woodpeckers observed. Mixed pine (Pinus spp.)-hardwood forests and pine uplands were occupied by approximately 2% of the observed red-headed woodpeckers each . Red-headed woodpeckers frequent savannas and forest edges during the breeding season, and mostly avoid the interior of forest patches >30 acres unless fire, wind damage, or some other event creates gaps in the forest interior . In Illinois, red-headed woodpeckers preferred the forest edge from late summer to early winter and the interior forest during the rest of the year . Red-headed woodpecker nests in Ohio were associated with low ground cover within a mosaic of agricultural and forested habitats . Oak woodlots with an abundance of "overmature" trees with dead branches and cavities support red-headed woodpeckers during years of high acorn mast . In South Dakota, red-headed woodpeckers were observed in riparian habitat adjacent to black-tailed prairie dog (Cynomys ludovicianus) colonies .
Mean habitat characteristics of a plains cottonwood-peachleaf willow (Populus deltoides ssp. monilifera-Salix amygdaloides) riparian stand in Colorado and 2 eastern cottonwood/Rocky Mountain juniper (P. deltoides/Juniperus scopulorum) stands in North Dakota inhabited by red-headed woodpeckers were:
|Mean canopy height
|Large tree density
|Medium tree density
|Small tree density
|North Dakota||15.3-18.5||70.0-85.0||20.0-21.0||7.7-14.8||95.8-103.7||79.0-82.0 |
Red-headed woodpecker habitat in a bottomland hardwood forest in Texas had an average of 4.3 trees greater than 15 inches (38 cm) DBH/0.04 ha and a dominant vegetation height of 108.9 feet (33.2 m) . In Illinois, there was a positive relationship between the number of red-headed woodpeckers and the number of oaks greater than 10 inches (25 cm) DBH (r=0.909, P<0.05 in year 1; r=0.961, P<0.01 in year 2) . More than half of all plains cottonwoods in a Colorado stand had an average DBH of 9 to 20 inches (24-52 cm) . Optimal stand structure for red-headed woodpeckers in longleaf pine-loblolly pine (Pinus palustris-P. taeda) stands in South Carolina would likely be DBH of 16 to 24 inches (40-61 cm) for cavity trees . Red-headed woodpeckers in Iowa responded negatively (R²=0.113, P≤0.01) to tree density but positively (R²=0.113, P≤0.01) to snag density. Red-headed woodpeckers also responded positively (R²=0.113, P≤0.01) to tree size and forb species richness. Snags with an average DBH of 20 to 30 inches (51-75 cm) were highly favored (R²=0.113, P≤0.01) .
In late seral stage stands in South Dakota, little mid-story vegetation was present. Average vegetation characteristics of late seral and late-intermediate seral stands in the plains cottonwood/willow (Salix spp.) riparian habitats occupied by red-headed woodpeckers were :
|Late intermediate seral stage||Late seral stage|
|% cover of vegetation <1 m tall||54.6||79.9|
|Number of cottonwood seedlings/acre||123.5||2.5|
|Number of willow seedlings/ha||46.2||8.4|
|Number of cottonwood trees/ha||949.7||116.5|
|Number of small snags/ha||52.1||0.0|
|Number of large snags/ha||0.7||6.1|
|Basal area of cottonwoods (m²/ha)||332.6||766.0|
|DBH of cottonwoods (cm)||17.0||67.3|
|% overstory canopy cover||58.7||48.5|
Snags are essential habitat components that are utilized for nesting, roosting, and foraging [35,38,69]. American beaver (Castor canadensis) ponds, open wooded swamps, rivers bordered by hardwoods, and other riparian or wetland areas where snags are plentiful provide valuable habitat [69,97]. Similarly, trees killed by flooding as well as those bordering lakes, marshes, and other frequently flooded areas support red-headed woodpecker populations . In addition, red-headed woodpeckers are highly attracted to forested areas that have been treated with herbicides and contain numerous standing snags . Snag densities averaged 0.66/ha in a plains cottonwood-dominated stand in Colorado . An average of 2.7 snags was present within 0.04-ha plots in a Texas bottomland hardwood forest. Average snag DBH was 9.5 inches (24.1 cm) .
Red-headed woodpeckers utilize live and dead trees for foraging . Foraging activities most often occurred in association with live trees (48.5%) followed by nest snags (29.5%) and other snags (22.1%) in Florida . Mean foraging height for the red-headed woodpecker depends on the condition of the trees used. In a Texas study, mean foraging height in live trees was 43 feet (13 m); in dead snags red-headed woodpeckers foraged at 39 feet (12 m) on average; and mean forage height was 41 feet (12.5 m) in live trees with dead limbs . Red-headed woodpecker activity was strongly restricted to the canopy, between 24.9 feet (7.6 m) above ground level to the canopy top, in a Louisiana bottomland hardwood forest .
Territory size/density: Small forest tracts are utilized if the habitat provides adequate nesting sites, roosting sites, and food. Red-headed woodpeckers in a South Carolina bottomland hardwood forest were most commonly detected in 0.5-ha gaps and least common in 0.06-ha gaps. Differences were not significant (P=0.26) . In Arkansas and Oklahoma, no red-headed woodpeckers were observed in forest gaps ranging 0.54 to 2.62 acres in size. However, red-headed woodpeckers were detected at an average density of 0.3 bird/acre in clearcuts 35 to 40 acres in size . In Virginia, red-headed woodpeckers nested in oak woodlots as small as 2 ha, while oak woodlots as small as 3 ha supported 2 breeding pairs .
Red-headed woodpeckers were observed at a rate of 0.59 bird/ha in late-seral cottonwood forests in South Dakota and at 0.05 bird/ha in late intermediate-seral forests during the breeding season . The difference was significant (P≤0.15) . No red-headed woodpeckers were detected in the early and early intermediate-seral stages in South Dakota .
Red-headed woodpecker densities and territory sizes vary greatly depending on location, habitat, and season. Densities during the breeding season are reported in the following table:
|Location||Habitat type||Average number of individuals||Average number of breeding pairs||Area|
|Colorado||mature plains cottonwood bottomland forest||9-16||....||100 ha [74,76]|
|plains cottonwood floodplain||20.0||....||40 ha |
|Illinois||urban and suburban residential||0-25||....||100 acres|
|oak-maple (Acer spp.) forest||3-6.0||....||100 acres|
|grazed bottomland woods||4||....||100 acres|
|mature bottomland forest||3.4||....||100 acres|
|mature upland forest||0.4||....||100 acres|
|second-growth hardwood forest||5.9-27||....||100 acres|
|swamp prairie||14.3||....||100 acres|
|oak-maple forest edge||13.7||....||1 mile of edge |
|Iowa||tallgrass prairie, mowed edge||1.15||....||1,000 m of edge|
|tallgrass prairie, burned edge||0.80||....||1,000 m of edge|
|tallgrass prairie, untreated edge||0.36||....||1,000 m of edge |
|Louisiana||water oak (Q. nigra)-loblolly pine-spruce pine (P. glabra)||11.0||....||100 acres |
|North Dakota||eastern cottonwood/Rocky Mountain juniper floodplain||....||4.3||40 ha |
|Oklahoma||shortleaf pine (P. echinata)-mixed oak upland forest||....||6.6||100 acres |
|South Carolina||longleaf pine-loblolly pine||....||2.3||100 acres |
Breeding territories in Florida ranged from 3.1 to 8.5 ha . Average territory size in Illinois was 5.5 to 11.0 ha .
Red-headed woodpecker densities during winter are reported in the following table:
|Average number of individuals||Area|
|Illinois||urban residential||0-0.5||100 acres|
|oak-maple forest||12.5||100 acres |
|mature bottomland forest||33.7-34.2||100 acres|
|mature upland forest||8.2-8.4||100 acres [34,35]|
|grazed bottomland forest||1.3||100 acres|
|shrubby field||0-7||100 acres|
|oak-maple forest edge||6.8||1 mile of edge |
|Maryland||pin oak-ash-black locust (Q. palustris-Fraxinus spp.-Robinia pseudoacacia)||12||1.25 ha |
Actual red-headed woodpecker population densities across all winter habitats in Illinois ranged from 0 to 89 individuals/100 acres .
Winter territories in an Ohio beech (Fagus spp.) grove averaged 0.05 ha for adults and 0.03 ha for juveniles . In Florida, winter territories averaged 1.00 ha for adults and 0.95 ha for juveniles in palmetto (Sabal spp.) scrub and oak scrub habitats . In Louisiana, winter territories averaged 0.8 to 1.2 ha .COVER REQUIREMENTS:
In Iowa, 88% of red-headed woodpecker nesting cavities was in snags . Snags with <34% of the total branches remaining were highly favored for nesting. Snags with >66 % of branches remaining were used least . This preference may be related to the softness of the wood due to decay [83,94]. In Wyoming, red-headed woodpeckers nested in limb cavities 80.6% of the time and in boles 19.4% of the time (P<0.001) . Red-headed woodpeckers nested in significantly (P=0.02) more snags (72.2%) than nonsnags (27.8%) .
The table below summarizes mean red-headed woodpecker nest site characteristics:
|State||Habitat type||Tree height (m)||Tree DBH (cm)||Cavity height (m)||Diameter of trunk/limb at nest (cm)|
|Arkansas||shortleaf pine-post oak (Q. stellata)||14.8||33.4||11.0||.... |
|Colorado||mature plains cottonwood||15.4||56.9-66.8||8.3-8.4||18.4 [7,75]|
|Florida||longleaf pine-turkey oak (Q. laevis) savanna||13.8||30.6||9.3||.... |
|Iowa||mixed riparian habitats||14.6||....||9.6||25.7 |
|Kansas||American elm (U. americana)-eastern cottonwood-willow||10.9||....||7.0||21.8 |
|Minnesota/Wisconsin||closed-canopy mature oak forest||18||54||....||.... |
|Ohio||mixed agricultural and forested habitat or oak-hickory (Carya spp.) stands bordering golf courses||18.3||56.9-58.8||10.2-14.1||20.7 [46,71]|
|Wyoming||mixed cottonwood-willow floodplain, irrigated cropland, and pastureland||....||59.2||10.0||21.2 |
|Virginia||mature oak woodlot||29.5||95.0||17.5||38.0 |
Nest cavities in an Illinois study were 23 to 66 feet (7-20 m) in height and always in the bole of a snag . All nest trees in Minnesota and Wisconsin had branch stubs and most had old cavities, <25% bark remaining, and at least one "significant dead portion" . Nest trees in Minnesota and Wisconsin had significantly greater diameters (P<0.001) and were significantly taller (P<0.001) than adjacent trees .
Red-headed woodpeckers have strong nest site and nest tree fidelity [5,44]. Cavities may be reused from year to year [5,44,94]. In Ohio, 57.7% of nest cavities had been freshly excavated, while 42.3% were old excavations . No natural cavities were used for nesting in Ohio . In Colorado, both limbs and trunks were utilized nearly equally for nesting, as were old and new cavities . Additionally, nest cavities previously excavated by other species, such as the red-cockaded woodpecker (Picoides borealis) and southern flying squirrel (Glaucomys volans), may be reused by red-headed woodpeckers in subsequent years . Red-headed woodpecker pairs occasionally take over cavities that were occupied by other species earlier in the same breeding season . Rarely, red-headed woodpeckers complete excavation of cavities that were abandoned by other species .
Roost trees of nonbreeding individuals in a Florida study were located in longleaf pine and turkey oak snags and in a dead limb of a live turkey oak tree . Juveniles showed a preference for roosting in turkey oaks while adults preferred roosting in longleaf pine snags .FOOD HABITS:
Red-headed woodpeckers exhibit a myriad of behaviors for obtaining and storing food. Perhaps the most conspicuous behavior is flycatching for beetles and other insects [6,48,56,63,91]. Flycatching is less frequent during winter due to a decrease in flying insects during colder months . Red-headed woodpeckers also glean insects, particularly adult beetles, from bark [16,48,94] and feed on insects on the ground [48,69]. Acorns are harvested both directly from trees and from the ground [17,82]. Red-headed woodpeckers may eat acorns immediately after harvesting, or carry them off to a cache .
Foods, including acorns and insects, are commonly cached in natural crevices and cavities, which are sealed with wet bark or wood to prevent pillaging by others [6,49]. Insects, such as June beetles (Phyllophaga spp.) and grasshoppers, are cached while still alive and wedged in cracks so they cannot escape [6,35]. Acorns and beechnuts are also stored in cracks and crevices for later use .PREDATORS:
Cooper's hawks (Accipiter cooperi), northern harriers (Circus cyaneus), red-tailed hawks (Buteo jamaicensis), peregrine falcons (Falco peregrinus), eastern screech-owls (Megascops asio), and red foxes (Vulpes vulpes) also prey upon red-headed woodpeckers [27,28,29,35,89].
Nest parasitism by brown-headed
cowbirds (Molothrus ater) is extremely rare .
A steep decline in the global population of red-headed woodpeckers has been documented since 1966 . Nationally, the average decline of the red-headed woodpecker was 2.6% annually between 1966 and 2005. From 1980 to 2005 the average decline was 4.2% annually. The declines for both periods are significant (P<0.01) . In the Midwest, red-headed woodpeckers have declined 3.3% per year for a total decline of 63.8% between 1966 and 1993 . Red-headed woodpecker declines in Florida are of high concern .
Collisions with automobiles [6,35] and competition for nesting cavities with other species, particularly European starlings and other woodpeckers, may be contributing to population decline [35,46]. In the past, red-headed woodpeckers were shot because they were considered agricultural pests in fruit groves and cornfields [6,35]. Red-headed woodpeckers also do considerable damage to utility poles and were shot as a result .
Habitat loss is likely the primary cause of the decline of the red-headed woodpecker population. Predicted responses of habitat changes on red-headed woodpeckers are :
|All woody vegetation removed, resulting in pastures or hayfields||Woody vegetation reduced to narrow strips along streams||Woody canopy partly removed||Woody canopy partly removed and shrubs/saplings thinned||Shrubs/saplings thinned||Snags removed|
|Extirpated from community||Negative||Positive||Positive||Positive||Negative|
Snag removal from wooded habitats has a drastic effect on the nesting potential of primary and secondary cavity nesters . Red-headed woodpeckers respond negatively to snag removal [14,21,54,94]. Management recommendations for red-headed woodpeckers in Virginia include retaining snags in woodlots and planting young trees over time to encourage replacement when large trees die . Failing to carry out this recruitment cycle may result in the elimination of mature woodlots in Virginia and the disappearance of the red-headed woodpecker in those areas . Illustrating this point, approximately 53.1% of tree cavities utilized by red-headed woodpeckers were no longer usable after 5 years in a cottonwood bottomland forest in Colorado .
In loblolly pine habitat in South Carolina, red-headed woodpeckers were most common where no coarse woody debris was removed (6.8 breeding territories/40 ha) . Red-headed woodpeckers were less common in plots where all down coarse woody debris was removed (3.6 breeding territories/40 ha) and least common in plots where all down coarse woody debris and all standing snags were removed (0.7 breeding territories/40 ha). The differences in breeding territory densities between the 3 stands were significant (P=0.023) . The optimal number of snags required by red-headed woodpeckers in longleaf pine-loblolly pine stands in South Carolina is at least 7 snags/100 acres . At least 1 snag/100 acres is required for red-headed woodpeckers to be present at all in longleaf and loblolly pine stands in South Carolina .
Red-headed woodpeckers in Texas were found in clearcuts with standing snags, but not in clearcuts without standing snags . A minimum of 5 snags/ha was assumed adequate for nesting in a clearcut, but a higher density of snags may promote more foraging and nesting on a site. A possible management strategy is to leave large numbers of hardwoods standing during harvesting operations and then killing the standing trees over time to provide a continual recruitment of snags for cavity nesters .Snags should be retained whenever possible . Since tree cavities are ephemeral, recruitment of new snags is crucial for red-headed woodpecker populations to persist.
|U.S. Department of the Interior, Fish and Wildlife Service, Sherburne National Wildlife Refuge|
Only one paper documenting the direct effects of fire on red-headed woodpeckers was found. In the study, a longleaf pine snag containing an active red-headed woodpecker nest ignited during a prescribed May fire in the Florida sandhills . The snag fell on the day of the fire and the nestlings initially survived. The parents continually visited and fed the nestlings. However, by the fourth day, the nestlings had died and were covered with ants . Based on these observations, it is plausible to conclude that the nestlings may have survived if they were within a few days of fledging.
The effects of fire on canopy nesting birds depend primarily on fire severity . Severe surface fires and crown fires may cause injury or death to species nesting in the forest canopy, but such fires typically happen late in the breeding season presumably after many nestlings have fledged. Effects on reproductive success may depend upon the timing of a fire event and any attempts to raise a second brood . See Timing of Major Life History Events for more information on the reproductive biology of the red-headed woodpecker.
Snags are both created and lost during fires. In a red-headed woodpecker study in the sandhills and wet pine flatwoods of central Florida, >33% of nest snags were created during past fires . In other minor habitat types in the study, 83% of nest snags were also created by fire. Prescribed fire later destroyed approximately 50% of the nest snags in the wet pine flatwoods, 70% of nest snags in the sandhills, and no nest snags in the other habitats. The sandhills were dominated by longleaf pine, the flatwoods were dominated by pond pine and longleaf pine, and the other habitats were dominated by sand pine (P. clausa), loblolly pine, and loblolly bay (Gordonia lasianthus) .
Fires that destroy nest trees may limit the reproductive potential of canopy-nesting birds. However, taking measures to protect nest trees may minimize the impact fire has on red-headed woodpeckers and their nests. In a review, Robbins and Myers  cited a North Carolina study in which red-cockaded woodpeckers were mildly affected by growing-season prescribed fires. Before the fires, flammable materials were cleared from the bases of nest trees. Four red-cockaded woodpecker nests in the study successfully fledged 9 young, while a fifth nest failed. Study recommendations for minimizing deleterious effects of growing-season fire on red-cockaded woodpeckers and their nests include: 1) burning only after nests have been identified; 2) burning only on sites with low fuel accumulation; 3) burning only on days with low ambient temperatures; 4) clearing fuels from the bases of nest trees; and 5) setting backfires to the windward side of nest trees . Since red-headed woodpeckers share some nesting preferences and habitats with the red-cockaded woodpecker, such as the use of large trees for nesting in pine habitats, red-headed woodpeckers may incur similar benefits from prefire site preparation.
Short-term food availability may be improved by fire. Other flycatching birds, such as eastern phoebes (Sayornis phoebe), eastern wood-pewees (Cantopus virens), eastern kingbirds (Tyrannus tyrannus), tree swallows (Tachycineta bicolor), southern rough-winged swallows (Stelgidopteryx ruficollis), and purple martins (Progne subis), actively forage on the multitude of insects available in smoke . Fruits, such as huckleberries and blackberries, that are also utilized as forage may be unavailable during the same year of a burn, but are often abundant during following years .HABITAT-RELATED FIRE EFFECTS:
In a Kansas tallgrass prairie, red-headed woodpeckers on average were observed in low abundance (0.3 bird/km) in unburned watersheds, while none were observed in burned watersheds. Less woody vegetation was present in the burned sites than in the unburned sites, which may account for the lack of forest-dependent red-headed woodpeckers .
In a mature longleaf pine-loblolly pine-shortleaf pine stand with an open hardwood understory, more nonbreeding red-headed woodpeckers were observed in stands burned under prescription during the dormant season (0.16/plot) compared to the number observed in stands burned under prescription during the growing season (0.07/plot) in Georgia. However, the results were not statistically significant (P=0.53). Stands were burned every 3 years . The opposite result was seen in a North Carolina study, where higher densities of red-headed woodpeckers were observed in plots burned under prescription during the growing season than in plots burned under prescription during the dormant season .
Mean observations of red-headed woodpeckers were higher in longleaf pine-loblolly pine-shortleaf pine/grassland restoration stands (0.14 detection/point count) than in traditionally managed longleaf pine-loblolly pine-shortleaf pine sawtimber stands (0.06 detection/point count) in Mississippi. The difference was nearly significant (P=0.08). The mixed pine-grassland restoration sites were even-aged stands with rotations ≥70 years, a prescribed burn interval of 2 to 3 years, and mid-story hardwood removal. Traditionally managed mixed pine sawtimber sites in the same study were subject to a 35-year rotation, prescribed burn intervals of 4 to 7 years, and no hardwood removal .
Red-headed woodpecker abundance was highest at the beginning of a fire exclusion regime in a loblolly pine-shortleaf pine stand in Florida. The lowest red-headed woodpecker abundance was continuously observed 6 to 15 years after fire exclusion was initiated. Hardwoods had created a thick mid-story up to 16 feet (5 m) following 15 years of fire exclusion . In another Florida study, red-headed woodpeckers were most commonly observed in mature burned sandhills of naturally seeded longleaf pine (>50 years old) where burning had occurred within the last 3 years and at least 1 growing season had passed since the last fire. Red-headed woodpeckers were also regularly observed in mature flatwoods that had been burned within the past 5 years in Florida .
The use of silvicultural treatments in addition to fire may alter the postfire response of the red-headed woodpecker. The combined effects of fire and other silvicultural treatments in a Florida longleaf pine habitat were examined. Two years after an initial prescribed burn, experimental treatments of herbicide (hexazinone) and chainsaw felling-girdling of most hardwoods and all sand pine were applied. A burn-only site and a control site were also monitored. A second prescribed burn was conducted in the spring 2 years after the other experimental treatments were applied. The herbicide-treated plots had the lowest abundance of red-headed woodpeckers in the year after the final prescribed burn, but the highest abundance among all treatments a year later. The burn-only plots and the felling-girdling plots had intermediate abundance of red-headed woodpeckers during both years of observation. No red-headed woodpeckers were observed in control plots. None of the differences were significant (P>0.05) .
The following table provides fire return intervals for plant communities and ecosystems where the red-headed woodpecker is important. For further information, see the FEIS review of the dominant plant species listed below.
|Community or Ecosystem||Dominant Species||Fire Return Interval Range (years)|
|maple-beech||Acer-Fagus spp.||684-1,385 [13,95]|
|silver maple-American elm||Acer saccharinum-Ulmus americana||<5 to 200|
|sugar maple||Acer saccharum||>1,000|
|sugar maple-basswood||Acer saccharum-Tilia americana||>1,000 |
|birch||Betula spp.||80-230 |
|plains grasslands||Bouteloua spp.||<35 [67,99]|
|sugarberry-America elm-green ash||Celtis laevigata-Ulmus americana-Fraxinus pennsylvanica||<35 to 200|
|beech-sugar maple||Fagus spp.-Acer saccharum||>1,000|
|black ash||Fraxinus nigra||<35 to 200 |
|green ash||Fraxinus pennsylvanica||<35 to >300 [24,95]|
|cedar glades||Juniperus virginiana||3-22 [37,67]|
|shortleaf pine||Pinus echinata||2-15|
|shortleaf pine-oak||Pinus echinata-Quercus spp.||<10|
|slash pine||Pinus elliottii||3-8|
|slash pine-hardwood||Pinus elliottii-variable||<35|
|sand pine||Pinus elliottii var. elliottii||25-45 |
|South Florida slash pine||Pinus elliottii var. densa||1-15 [64,81,95]|
|longleaf-slash pine||Pinus palustris-P. elliottii||1-4 [64,95]|
|longleaf pine-scrub oak||Pinus palustris-Quercus spp.||6-10|
|pond pine||Pinus serotina||3-8|
|eastern white pine-northern red oak-red maple||Pinus strobus-Quercus rubra-Acer rubrum||35-200|
|loblolly pine||Pinus taeda||3-8|
|loblolly-shortleaf pine||Pinus taeda-P. echinata||10 to <35|
|Virginia pine||Pinus virginiana||10 to <35|
|Virginia pine-oak||Pinus virginiana-Quercus spp.||10 to <35|
|sycamore-sweetgum-American elm||Platanus occidentalis-Liquidambar styraciflua-Ulmus americana||<35 to 200 |
|eastern cottonwood||Populus deltoides||<35 to 200 |
|black cherry-sugar maple||Prunus serotina-Acer saccharum||>1,000|
|northeastern oak-pine||Quercus-Pinus spp.||10 to <35 |
|oak-gum-cypress||Quercus-Nyssa-spp.-Taxodium distichum||35 to >200 |
|southeastern oak-pine||Quercus-Pinus spp.||<10|
|white oak-black oak-northern red oak||Quercus alba-Q. velutina-Q. rubra||<35|
|northern pin oak||Quercus ellipsoidalis||<35|
|bear oak||Quercus ilicifolia||<35|
|bur oak||Quercus macrocarpa||<10 |
|oak savanna||Quercus macrocarpa/Andropogon gerardii-Schizachyrium scoparium||2-14 [67,95]|
|chestnut oak||Quercus prinus||3-8|
|northern red oak||Quercus rubra||10 to <35|
|post oak-blackjack oak||Quercus stellata-Q. marilandica||<10|
|live oak||Quercus virginiana||10 to<100 |
|cabbage palmetto-slash pine||Sabal palmetto-Pinus elliottii||<10 [64,95]|
FIRE REGIMES : Find fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find Fire Regimes".
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