By Phil Spivey
September 2010: The red-cockaded woodpecker is one persnickety little critter.
While this woodpecker may superficially resemble several other woodpecker species found in Georgia, it is unique in many respects, especially in its unwavering affinity for old pine forests with a very open understory resulting from repeated fires—which these days usually means controlled burns. (Historically, lightning strikes or Native Americans would have started these fires, and back then there were no roads, towns and cities or any other reason to impede runaway fires.)
Red-cockaded woodpeckers, commonly called RCWs by scientists, prefer longleaf pine forests more than 100 years old usually in the Coastal Plain, but they will use loblolly and shortleaf pine forests in the Piedmont. The woodpeckers are also unique in the way they build nesting and roost cavities within live pine trees. These older trees are more likely to have red heart fungus, which attacks the innermost heartwood of the tree, making it easier to excavate a cavity.
Unfortunately, most forest owners are reluctant to let their timber grow to such a ripe old age. Examples of this habitat in Georgia occur on large tracts of public land, especially forts Benning and Stewart, Piedmont National Wildlife Refuge, and private quail hunting properties in southwest Georgia. Most large red-cockaded woodpecker populations are found on these wild lands where habitat is suitable and the acreage is sufficient. The only population on state lands is on Silver Lake Wildlife Management Area in Decatur County.
It is not difficult to understand the rarity of this bird considering the requirement of very old trees and the frequent exposure to fire. A handful of much smaller populations occur in Georgia but are prone to severe demographic isolation and lack of suitable habitat. This has been the case with dozens of small red-cockaded woodpecker populations in the last few years.
These woodpeckers have a complex social structure and live in family groups usually made up of an adult breeding pair and several (one to six) “helpers,” or young male offspring from previous years. All live in a “cluster” of eight to 10 cavity trees within their home territory, which may cover from 50 to 500 acres depending on habitat quality. Each adult meticulously flakes all loose bark from around the cavity and drills tiny “resin wells” from which flow copious amounts of resin that wards off nest competitors and predators.
Helpers assist with various tasks like maintaining roosting cavities, defending their territory and raising young. Their hope is to inherit the cluster of cavities and start their own family. This may seem like an odd strategy until you consider it may take several decades to build enough roosting cavities to support a family.
The red-cockaded woodpecker was listed as endangered in 1968, before the federal Endangered Species Act existed. The following saga has unfolded with a few lows but more recently a series of highs that have more or less secured the future of this rare bird, at least on public lands across the Southeast.
One of the definite highs has been the ability to move or “translocate” individual red-cockaded woodpeckers into new suitable habitats. This technique seems like an obvious management tool, but it proved a challenging one.
Back in 1980, Ron Odum, a biologist working for the Georgia Department of Natural Resources, and several other biologists from the U.S. Fish and Wildlife Service and Fort Stewart coordinated the translocation of a dozen red-cockaded woodpeckers from Stewart, near Hinesville, to an old-growth longleaf pine stand on St. Catherine’s Island, on the Georgia coast.
Each bird was carefully netted from its roost cavity during the night and color-banded for later identification. Researchers even went to the trouble of cutting out the original cavities from the trees on Fort Stewart and placing them in new trees on St. Catherine’s. The birds were a mixture of juvenile and older adults. One pair nested and fledged young soon after being moved. The other birds filtered into the landscape with the remains of two being found after presumably being eaten by hawks. One individual male found his way to Sapelo Island, created his own cavity and remained there alone for many years.
This effort represented the first attempt to translocate red-cockaded woodpeckers into new habitat, and even though the results were mixed, much was learned. Today, the technique has been refined through years of serious scientific research and some trial and error. We now move only juvenile birds generally 6-8 months old, since adult birds don’t take well to being moved from the natal home range. Other rules are also followed that ensure the donor population has enough juvenile woodpeckers to fill breeding vacancies within the population.
We have learned that many juvenile red-cockaded woodpeckers simply disappear from most small populations, presumably because they lack sufficient habitat or roosting cavities. We also better understand the social structure of the family groups and know that most juvenile birds, especially females, will be pushed away from the family during their first year. Through the capture and translocation of these young birds, we are focusing recruitment into places where it is needed most. In fact, it has been shown that translocated red-cockaded woodpeckers have a higher survival rate than birds left to disperse on their own.
The overall goal is to increase the number of family groups within a population to the point it may be stable over the long-term. Such success has been accomplished at the Joseph W. Jones Ecological Research Center in Baker County, where the translocation of about 50 young red-cockaded woodpeckers since 1999 has established a population of 24 family groups.
Other efforts have shown similar success. The population at Silver Lake WMA has grown to 21 family groups through translocation of juvenile birds, a process started by International Paper Co., the former owner of the 8,432-acre site near Bainbridge.
Very recently, in Tallahassee, FL, a group of mostly state and federal government biologists, foresters, consultants and other private land managers from across the Southeast met to decide the destination of about 120 juvenile red-cockaded woodpeckers. The RCW Southern Range Translocation Cooperative meeting included debate about habitat conditions, vulnerability of small populations, ability to conduct control burns, the woodpeckers’ reproduction success, proximity to other populations, potential for artificial recruitment clusters, and other factors.
These young birds are taken in pairs from so-called donor populations, which are generally the largest, most robust red-cockaded woodpecker populations such as at Fort Benning and Stewart in Georgia, and moved to recipient populations sometimes hundreds of miles away. The typical translocation consists of six to 10 young birds. Great care is taken to ensure unrelated birds are paired and that their new homes of artificial cavities are in prime shape.
In the end, a large map of all red-cockaded woodpecker populations in the Southeast is bristling with color-coded pins representing each bird and its destination, all a result of what amounts to be the eHarmony process for woodpeckers.
And this fall biologists will filter through the dark piney woods toting long-handled wispy nets and looking for young unsuspecting woodpeckers nestled in their beds with no idea of the great adventure that lies ahead.
Translocation Update 2010
This fall, 11 young woodpeckers will make the journey from Eglin Air Force Base in Florida’s western panhandle to Silver Lake WMA, just outside of Bainbridge. The total will include three male-female pairs and five single females. The five singles are significant because we hope they will pair with single males already at Silver Lake. New artificial cavities will await the young birds for roosting at night and hopefully raising a new family next spring.
Phil Spivey is a wildlife biologist who works with red-cockaded woodpeckers for the Georgia DNR’s Nongame Conservation Section.
The red-cockaded woodpecker is one persnickety little critter.