The red-cockaded woodpecker (Dryobates borealis) is a woodpecker endemic to the southeastern United States. It is a threatened species under the Endangered Species Act of 1973.

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 in length, spans across the wings and weighs . Among the standard measurements, the wing chord is , the tail is , the bill is and the tarsus is . 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

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. 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.

The red-cockaded woodpecker is a cavity-nester. They excavate cavities in live pine trees, favoring the longleaf pine. It can take the birds anywhere from under a year to several decades to excavate a cavity. Cavity excavation in longleaf pine takes an average of 4.4 years to complete.

thumb|Detail of head

Ecology

The red-cockaded woodpecker is a keystone species in southern pine forest ecosystems. mammals (e.g., evening bat), 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.

left|190x190px|thumb|Male at nest cavity in longleaf pineIn 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.

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.

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. Southern flying squirrel exclusion devices may be considered as well. 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. Application of capsaicin on flying squirrel at cavities could be a cost-effective method.

See also

  • Babbitt v. Sweet Home Chapter of Communities for a Great Oregon

References

Further reading

  • BirdLife Species Factsheet.
  • The Nature Conservancy's Species page: Red Cockaded woodpecker
  • Red-cockaded woodpecker photo gallery VIREO*Red-cockaded woodpecker videos on the Internet Bird Collection
  • A little bit more about the red-cockaded woodpecker and a few other endangered birds
  • Ecos.fws.gov, Species Profile
  • W.G.Jones State Forest, Conroe, Texas
  • Red-cockaded woodpecker at Longleaf Alliance