Red-cockaded woodpecker

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Red-cockaded woodpecker
Picoides borealis USMC2005729133853B.jpg
Female with insect prey in mouth
Status TNC G3.svg
Vulnerable  (NatureServe) [2]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Piciformes
Family: Picidae
Genus: Leuconotopicus
Species:
L. borealis
Binomial name
Leuconotopicus borealis
(Vieillot, 1809)
Dryobates borealis map.svg
Current range [3]
Synonyms [4]
  • Dendrocopos borealis borealis (Vieillot, 1809)
  • Picoides borealis hylonomus (Wetmore, 1941)
  • Dryobates borealis (Vieillot, 1809)
  • Dendrocopos borealis hylonomus (Wetmore, 1941)
  • Picoides borealis borealis (Vieillot, 1809)
  • Dendrocopos borealis (Vieillot, 1809)
  • Picoides borealis(Vieillot, 1809)

The red-cockaded woodpecker (Leuconotopicus borealis) is a woodpecker endemic to the southeastern United States. [5] [6] It is a federally endangered species under the Endangered Species Act of 1973. [7] [8]

Description

The red-cockaded woodpecker is small- to mid-sized species, being intermediate in size between North America's two most widespread woodpeckers (the downy and hairy woodpeckers). This species measures 18–23 cm (7.1–9.1 in) in length, spans 34–41 cm (13–16 in) across the wings and weighs 40–56 g (1.4–2.0 oz). [6] [9] [10] Among the standard measurements, the wing chord is 9.5–12.6 cm (3.7–5.0 in), the tail is 7–8.2 cm (2.8–3.2 in), the bill is 1.9–2.3 cm (0.75–0.91 in) and the tarsus is 1.8–2.2 cm (0.71–0.87 in). [11] Its back is barred with black and white horizontal stripes. The red-cockaded woodpecker's most distinguishing feature is a black cap and nape that encircle large white cheek patches. Rarely visible, except perhaps during the breeding season and periods of territorial defense, the male has a small red streak on each side of its black cap called a cockade, hence its name. The species is listed as Near Threatened by the IUCN [1] and as Endangered by the United States Fish and Wildlife Service. [12] [13]

Behavior

The red-cockaded woodpecker feeds primarily on ants, beetles, cockroaches, caterpillars, wood-boring insects, and spiders, and occasionally fruit and berries. The vast majority of foraging is on pines, with a strong preference for large trees, though they will occasionally forage on hardwoods and even on corn earworms in cornfields. [14]

Red-cockaded woodpeckers are a territorial, nonmigratory, cooperative breeding species, frequently having the same mate for several years. The nesting season runs from April to June. The breeding female lays three to four eggs in the breeding male's roost cavity. Group members incubate the small white eggs for 10–13 days. Once hatched, the nestlings remain in the nest cavity for about 26–29 days. Upon fledging, the young often remain with the parents, forming groups of up to nine or more members, but more typically three to four members. There is only one pair of breeding birds within each group, and they normally only raise a single brood each year. The other group members, called helpers, usually males from the previous breeding season, help incubate the eggs and raise the young. Juvenile females generally leave the group before the next breeding season, in search of solitary male groups. The main predators of red-cockaded nests are rat snakes, although corn snakes also represent a threat. [15] Studies have also explored the possibility that southern flying squirrels might have a negative impact on red-cockaded woodpecker populations due competition over cavities and predation on eggs and nestlings. [16]

Distribution and habitat

Historically, this woodpecker's range extended in the southeastern United States from Florida to New Jersey and Maryland, as far west as eastern Texas and Oklahoma, and inland to Missouri, Kentucky, and Tennessee. Today it is estimated that there are about 5,000 groups of red-cockaded woodpeckers, or 12,500 birds, from Florida to Virginia and west to southeast Oklahoma and eastern Texas, representing about one percent of the woodpecker's original population (over 1 million individuals at one point). They have become locally extinct (extirpated) in Kentucky, Maryland, Missouri, New Jersey, and Tennessee. [17]

The red-cockaded woodpecker makes its home in fire-dependent pine savannas. [17] Longleaf pines (Pinus palustris) are most commonly preferred, but other species of southern pine are also acceptable. While other woodpeckers bore out cavities in dead trees where the wood is rotten and soft, the red-cockaded woodpecker is the only one that excavates cavities exclusively in living pine trees. The older pines favored by the red-cockaded woodpecker often suffer from a fungal infection called red heart rot which attacks the center of the trunk, causing the inner wood, the heartwood, to become soft. Cavities are generally excavated over 1 to 3 years.

The aggregate of cavity trees is called a cluster and may include 1 to 20 or more cavity trees on 3 to 60 acres (12,000 to 240,000 m2). The average cluster is about 10 acres (40,000 m2). Cavity trees that are being actively used have numerous, small resin wells which exude sap. The birds keep the sap flowing apparently as a cavity defense mechanism against rat snakes and possibly other predators. The typical territory for a group ranges from about 125 to 200 acres (500,000 to 800,000 m2), but observers have reported territories running from a low of around 60 acres (240,000 m2), to an upper extreme of more than 600 acres (2.40 km2). The size of a particular territory is related to both habitat suitability and population density. Where red-cockaded woodpeckers occur at high densities, individuals appear to spend more time in territorial defense, potentially at the expense of foraging and time allocated to reproduction, resulting in reduced clutch size and fledgling production. [18]

The red-cockaded woodpecker plays a vital role in the intricate web of life of the southern pine forests. A number of other birds and small mammals use the cavities excavated by red-cockaded woodpeckers, such as chickadees, bluebirds, titmice, and several other woodpecker species, including the downy, hairy, and red-bellied woodpeckers. Larger woodpeckers such as northern flicker, red-bellied or pileated woodpecker may take over a red-cockaded woodpecker cavity, sometimes enlarging the hole enough to allow eastern screech owls, wood ducks, and even raccoons to move in later. Flying squirrels, several species of reptiles and amphibians, and insects, primarily bees and wasps, also will use red-cockaded woodpecker cavities.

Detail of head Picoides borealisEHP10CC1.jpg
Detail of head

Ecology

A significant competitor is the pileated woodpecker (Dryocopus pileatus), who is known for doubling the width of cavities in trees, making the tree as a whole uninhabitable to the red-cockaded woodpecker. [19]

Conservation

The red-cockaded woodpecker suffers from habitat fragmentation when habitable pines are removed. When a larger cluster of birds gets split up, it is difficult for the young to find mates and eventually becomes an issue regarding species dispersal. [20] While dispersing in search of new places to settle, the red-cockaded woodpecker encounters habitats of competing woodpecker species.

The red-cockaded woodpecker has been the focus of conservation efforts even before the passing of the Endangered Species Act in 1973. In Florida, pairs are being released at DuPuis Management Area and other privately-owned land.

Due to the high importance of nesting habitat on the woodpecker's reproduction, much management has been dedicated to create ideal and more numerous nesting sites. Nesting clusters have been spared from forestry activity to preserve old-growth, large diameter trees. The nesting sites themselves have also been managed to make them more appealing. The use of controlled burning has been used to reduce deciduous growth around nesting colonies. The red-cockaded woodpecker has been shown to prefer nesting sites with less deciduous growth. The use of controlled burning must be exercised with caution due to the highly flammable resin barriers formed by the woodpecker. [21]

Male at nest cavity in longleaf pine Picoides borealisPCCA20060409-3008B.jpg
Male at nest cavity in longleaf pine

In an effort to increase the red-cockaded woodpecker population, states such as Texas, Louisiana, Alabama, and Georgia's wildlife management are creating artificial cavities in Longleaf Pine trees. There are two methods in which wildlife management officers use to insert cavities in long leaf pines. The most respected and latest approach is to carve out a nesting cavity in the tree and insert a man-made rot-resistant wooden box with a PVC pipe small enough for only a red-cockaded woodpecker to fit through. These boxes, also known as "inserts", can last up to 10 years. The older and less used approach is to drill a cavity into the tree in hopes that the birds will settle there and nest. [22]

Due to the energetically expensive process of excavating new cavities, more energy is expended competing for existing home ranges rather than colonizing new areas. Cavities are highly sought-out resources by all cavity dwelling species and red-cockadeds have been observed roosting in them as early as the same night the boxes are installed. Alpha males usually reside in the best cavity, alpha females in the second best cavity until breeding season when their male partners allow their cavity to turn into the nest cavity. Juveniles are left with the lower quality cavities or no cavities at all, forcing them to roost on a branch outside overnight. Due to the fact that each family member requires a cavity to roost, land managers may choose to insert additional artificial cavities to boost survival of juveniles. Red-cockaded woodpeckers will even recolonize abandoned ranges when cavities are created. [23]

In addition to the creation of new cavities, methods for protecting existing cavities are also used. The most common technique employed is a restrictor plate. The plate prevents other species from enlarging or changing the shape of the cavity entrance. These restrictor plates must be carefully monitored, however, to ensure that no hindrance is given to the woodpecker. Adjustments must also be made as the tree grows. [24] Southern flying squirrel exclusion devices may be considered as well. [25] A study suggested that managers establish new woodpecker clusters away from streams and limit the use of excess cavities, both factors important in the recruitment of flying squirrels. [26] Application of capsaicin on flying squirrel at cavities could be a cost-effective method. [27]

Intentional habitat destruction by landowners

Private landowners are prohibited from modifying habitats or taking animals that are protected by the Endangered Species Act (ESA). In response to the listing of the red-cockaded woodpecker, it became common in Eastern Texas for landowners to begin cutting down the long-leaf pine trees so that the woodpeckers would not nest in their trees. [20] [28] By eliminating the trees on a piece of privately owned land, the land owners no longer have to abide by the requirements of the U.S. Fish and Wildlife Service biologists. By removing available habitat for the endangered species, landowners are able to benefit economically and maintain construction rights to the property. [29] This led to the development of the Safe Harbor Agreements in which landowners agreed to manage their land in consistency with the conservation of a species of special conservation concern in return for relaxed ESA protection rules that allow a more flexible management of their own land.

See also

Related Research Articles

<span class="mw-page-title-main">Woodpecker</span> Family of birds (Picidae)

Woodpeckers are part of the bird family Picidae, which also includes the piculets, wrynecks and sapsuckers. Members of this family are found worldwide, except for Australia, New Guinea, New Zealand, Madagascar and the extreme polar regions. Most species live in forests or woodland habitats, although a few species are known that live in treeless areas, such as rocky hillsides and deserts, and the Gila woodpecker specialises in exploiting cacti.

<span class="mw-page-title-main">Pileated woodpecker</span> Species of bird

The pileated woodpecker is a large, mostly black woodpecker native to North America. An insectivore, it inhabits deciduous forests in eastern North America, the Great Lakes, the boreal forests of Canada, and parts of the Pacific Coast. It is the largest confirmed extant woodpecker species in North America, with the possible exception of the ivory-billed woodpecker, which the U.S. Fish and Wildlife Service has proposed be reclassified as extinct. It is also the third largest species of woodpecker in the world, after the great slaty woodpecker and the black woodpecker. "Pileated" refers to the bird's prominent red crest, from the Latin pileatus meaning "capped".

<span class="mw-page-title-main">Red-headed woodpecker</span> Species of bird

The red-headed woodpecker is a mid-sized woodpecker found in temperate North America. Its breeding habitat is open country across southern Canada and the east-central United States. It is rated as least concern on the International Union for Conservation of Nature (IUCN)'s Red List of Endangered species, having been down-listed from near threatened in 2018.

<span class="mw-page-title-main">Hairy woodpecker</span> Species of bird

The hairy woodpecker is a medium-sized woodpecker that is found over a large area of North America. It is approximately 250 mm (9.8 in) in length with a 380 mm (15 in) wingspan. With an estimated population in 2020 of almost nine million individuals, the hairy woodpecker is listed by the IUCN as a species of least concern. Some nomenclature authorities, such as the eBird/Clements checklist, place this species in the genus Dryobates.

<span class="mw-page-title-main">Downy woodpecker</span> Species of woodpecker

The downy woodpecker is a species of woodpecker, the smallest in North America. Length ranges from 14 to 18 cm. Downy woodpeckers primarily live in forested areas throughout the United States and Canada, with the exception of deserts in the southwest and the northern tundra. The bird nests in tree cavities and feeds primarily on insects, although it supplements its diet with seeds and berries. The downy woodpecker is very similar in appearance to the hairy woodpecker, although they are not closely related.

<span class="mw-page-title-main">Acorn woodpecker</span> Species of bird

The acorn woodpecker is a medium-sized woodpecker with a length of around 20 cm (8 in), and an average weight of 85 g (3.0 oz). It is found across Central America, as well as the western United States and parts of Colombia.

<span class="mw-page-title-main">Red-bellied woodpecker</span> Species of bird

The red-bellied woodpecker is a medium-sized woodpecker of the family Picidae. It breeds mainly in the eastern United States, ranging as far south as Florida and as far north as Canada. Though it has a vivid orange-red crown and nape it is not to be confused with the red-headed woodpecker, a separate species of woodpecker in the same genus with an entirely red head and neck that sports a solid black back and white belly. The red-bellied earns its name from the pale reddish blush of its lower underside.

<span class="mw-page-title-main">Eastern screech owl</span> Species of owl

The eastern screech owl or eastern screech-owl, is a small owl that is relatively common in Eastern North America, from Mexico to Canada. This species resides in most types of woodland habitats across its range, and is relatively adaptable to urban and developed areas compared to other owls. Although it often lives in close proximity to humans, the eastern screech owl frequently avoids detection due to its strictly nocturnal habits.

<span class="mw-page-title-main">White-breasted nuthatch</span> Species of bird

The white-breasted nuthatch is a species of bird in the nuthatch family Sittidae. It is a medium-sized nuthatch, measuring approximately 15.5 cm (6.1 in) in length. Coloration varies somewhat along the species' range, but the upperparts are light blue-gray, with a black crown and nape in males, while females have a dark gray crown. The underparts are whitish, with a reddish tinge on the lower abdomen. Despite not being closely related, the white-breasted nuthatch and the white wagtail are very similar in plumage. The white-breasted nuthatch is a noisy bird. It has a nasal voice and often utters little cries or vocalizations, often composed of repetitions of small invariant whistles. In summer, it is an exclusively insectivorous bird, consuming a wide range of arthropods, but in winter its diet consists mainly of seeds. The nest is located in the cavity of a tree. The clutch consists of five to nine eggs, incubated for two weeks by the female, who is fed by the male. The two adults then feed the young until they fledge, and for a few weeks after that.

<span class="mw-page-title-main">Spotted owl</span> Species of owl

The spotted owl is a species of true owl. It is a resident species of old-growth forests in western North America, where it nests in tree hollows, old bird of prey nests, or rock crevices. Nests can be between 12 and 60 metres high and usually contain two eggs. It is a nocturnal owl which feeds on small mammals and birds. Three subspecies are recognized, ranging in distribution from British Columbia to Mexico. The spotted owl is under pressure from habitat destruction throughout its range, and is currently classified as a near-threatened species.

<span class="mw-page-title-main">Bird nest</span> Place where a bird broods its eggs

A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American robin or Eurasian blackbird, or the elaborately woven hanging nest of the Montezuma oropendola or the village weaver—that is too restrictive a definition. For some species, a nest is simply a shallow depression made in sand; for others, it is the knot-hole left by a broken branch, a burrow dug into the ground, a chamber drilled into a tree, an enormous rotting pile of vegetation and earth, a shelf made of dried saliva or a mud dome with an entrance tunnel. The smallest bird nests are those of some hummingbirds, tiny cups which can be a mere 2 cm (0.8 in) across and 2–3 cm (0.8–1.2 in) high. At the other extreme, some nest mounds built by the dusky scrubfowl measure more than 11 m (36 ft) in diameter and stand nearly 5 m (16 ft) tall. The study of birds' nests is known as caliology.

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<span class="mw-page-title-main">White-headed woodpecker</span> Species of bird

The white-headed woodpecker is a non-migratory woodpecker that resides in pine forests of the mountains of western North America.

<span class="mw-page-title-main">Strickland's woodpecker</span> Species of bird

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<span class="mw-page-title-main">Swift parrot</span> Critically endangered species of Australian bird

The swift parrot is a species of broad-tailed parrot, found only in southeastern Australia. The species breeds in Tasmania during the summer and migrates north to south eastern mainland Australia from Griffith-Warialda in New South Wales and west to Adelaide in the winter. It is a nomadic migrant, and it settles in an area only when there is food available. The Swift Parrot was voted 2023 Bird of the Year in The Guardian Australia and BirdLife Australia’s biennial poll.

<span class="mw-page-title-main">Magellanic woodpecker</span> Species of bird

The Magellanic woodpecker is a species of large woodpecker found in southern Chile and southwestern Argentina; it is resident within its range. This species is the southernmost example of the genus Campephilus, which includes the famous ivory-billed woodpecker.

<span class="mw-page-title-main">Bird colony</span> Large congregation of birds at a particular location

A bird colony is a large congregation of individuals of one or more species of bird that nest or roost in proximity at a particular location. Many kinds of birds are known to congregate in groups of varying size; a congregation of nesting birds is called a breeding colony. Colonial nesting birds include seabirds such as auks and albatrosses; wetland species such as herons; and a few passerines such as weaverbirds, certain blackbirds, and some swallows. A group of birds congregating for rest is called a communal roost. Evidence of colonial nesting has been found in non-neornithine birds (Enantiornithes), in sediments from the Late Cretaceous (Maastrichtian) of Romania.

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References

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Further reading