Department of Biological Science, Florida State University, Tallahassee, Florida 32306 USA The Red-cockaded Woodpecker (Picoides borealis) is a federally endangered species, which inhabits pine forests in the southeastern United States (Ligon 1970). Red-cockaded Woodpeckers excavate cavities for roosting and nesting in mature, living pine trees (Ba- ker 1971), preferably longleaf pine (Pinus palustris) infected by redheart disease (Fomes pini) (Lennartz et al. 1983). Excavation of a single cavity may require a year or more, and it has been suggested that cavity trees are the primary ecological constraint that shaped the evolution of the cooperative breeding system of the Red-cockaded Woodpecker (Lennartz et al. 1987, Walters et al. 1988). Natural disturbance is an important component of the southeastern pine forests inhabited by the Red- cockaded Woodpecker (Christensen 1977). Frequent surface fires maintain the open habitat favored by Red-cockaded Woodpeckers (Ligon et al. 1986). High winds and lightning associated with frequent sum- mer thunderstorms and, less frequently, tornadoes and hurricanes are important sources of mortality among larger pines (Platt et al. 1988). In late summer and autumn 1985, three major storms struck the northeastern Gulf of Mexico: tropical storm Juan, and hurricanes Elena and Kate. The combination of heavy rain that saturated the soil and strong winds damaged some forests in northern Florida and southern Geor- gia. Trees were blown over and tree trunks snapped. During hurricane Kate, downbursts of wind gusting to 160 km per hour were estimated for Leon County, Florida (Clark 1986). We report the damage caused by these storms (mostly hurricane Kate) to Red-cock- aded Woodpecker cavity trees in an old-growth long- leaf pine forest in southern Georgia. The Wade Tract, an 80-ha conservation easement managed by Tall Timbers Research Station in south-  Present address: Tall Timbers Research Station, Route 1, Box 678, Tallahassee, Florida 32312 USA. 2 Present address: Department of Public Health Sci- ences, The Bowman Gray School of Medicine, Wake Forest University, 300 South Hawthorne Road, Win- ston-Salem, North Carolina 27103 USA. ern Thomas County, Georgia, contains one of the larg- est remaining old-growth longleaf pine populations. As part of a long-term study of life history dynamics (Platt et al. 1988), all pines taller than breast height (1.5 m) on a 46-ha section of the Wade Tract were given identification numbers on metal tags in 1979. The diameter at breast height (DBH) of all tagged trees was recorded in 1979, and the surviving tagged trees were remeasured in 1984. Tagged trees were censused annually for mortality through 1987. Red-cockaded Woodpeckers are common in the Wade Tract (Engstrom 1982). Some Red-cockaded Woodpecker nest trees were identified in 1979, but no systematic inventory of cavity trees was done be- fore the storms in autumn 1985. In the spring of 1986, Engstrom visually inspected trees in the Wade Tract during a study of hurricane damage to the entire forest. All Red-cockaded Woodpecker cavity trees in the 46-ha study site were located at this time. Among nearly 7,800 marked and measured trees that were standing before the storms in the autumn of 1985, 33 were Red-cockaded Woodpecker cavity trees. These cavity trees ranged in size from 30 to 69.2 cm DBH (œ = 49.0 cm; Fig. 1). Of 33 Red-cockaded Woodpecker cavity trees, 8 (24%) were killed during autumn 1985 (4 during hurricane Kate). Trunks of six of the eight trees snapped off at the site of the woodpecker cavity; trunks of the re- maining two trees snapped below the cavity. Five of the eight Red-cockaded Woodpecker cavity trees that were snapped off had rotten heartwood most likely caused by redheart disease. The remaining three trees did not have obviously rotten heartwood at the point of the snapped trunk. Four additional cavity trees suffered a loss of large limbs or a gash in the trunk that may increase the chance of mortality over the next decade. On the Wade Tract, age (measured with increment cores) and size (DBH) of 399 randomly selected long- leaf pine trees are highly correlated (Platt et al. 1988). Trees of approximately 30 cm DBH in this random sample ranged from just under 40 to over 80 years old, and trees with diameters of approximately 60 cm DBH ranged from roughly 180 to 240 years old. A1- 5O o Diameter (crn) Fig. 1. Available trees (n = 7,766) and trees used by Red-cockaded Woodpeckers for cavities (n = 33) on the Wade Tract. though the relationship between size and age of long- leaf pine trees has a large variance among trees older than 80 years, Red-cockaded Woodpeckers clearly se- lected larger (thus older) trees for cavity sites on the Wade Tract (Fig. 1). Contrary to the conclusions drawn by Field and Williams (1985) from a literature review, we found that Red-cockaded Woodpeckers prefer old- er trees for cavities, in agreement with other studies (Jackson et al. 1979, Jackson and Jackson 1986, De- Lotelle and Epting 1988). Trees in the size classes from 30 to 70 cm DBH (the classes used by Red-cockaded Woodpeckers on the Wade Tract) are a fairly stable resource in nonhur- ricane years. Only 2.7% of all trees in these size classes died during the 4-yr period from 1980 to 1983 (Platt et al. 1988). We cannot directly estimate the proba- bility of mortality among cavity trees during years without hurricanes, because cavity trees had not been systematically identified before 1985. Nevertheless, the 25% mortality of cavity trees during autumn 1985 appears to be at least an order of magnitude greater than the mortality expected to occur during the same interval in nonhurricane years. Even though not all cavity trees of the Red-cock- aded Woodpecker were used actively by birds in 1985, the abrupt elimination of available cavities may ad- versely affect survival of the species. Many animals other than Red-cockaded Woodpeckers use Red-cock- aded Woodpecker cavities (Harlow and Lennartz 1983). Competition from other animals for cavities for roost- ing and nesting could increase as a result of the short- age of available cavities caused by hurricane damage. Red-cockaded Woodpeckers that are forced to roost out of cavities may be more likely to die from in- creased exposure to inclement weather or predation. The loss of nearly one quarter of the Red-cockaded Woodpecker cavity trees on the Wade Tract within a few months represents a rare but severe reduction of a normally stable resource for this endangered species. Because several years may be required for the species to replace the cavities that were lost, long-term effects of the 1985 storms on the Wade Tract Red-cockaded Woodpecker population are currently unknown. Damage to mature pine trees used by Red-cockaded Woodpeckers for nesting and roosting on the Wade Tract could be classified as a severe disturbance. The degree of destruction on the Wade Tract may be minor compared with the extensive damage caused by hur- ricane Hugo to the Francis Marion National Forest in September 1989. Management and recovery plans for endangered species such as the Red-cockaded Wood- pecker must include the possible effects of infrequent disturbances or catastrophes such as hurricanes. This research was funded by Tall Timbers Research Station and National Science Foundation Grant DEB 8012090. We thank William Platt and Stephen Rath- bun for the use of their data on the trees of the Wade Tract. Gregory Butcher, Danny Ingold, and an anon- ymous reviewer made useful comments on the manu- script. LITERATURE CITED BAKER, W.W. 1971. Progress report on life history studies of the Red-cockaded Woodpecker at Tall Timbers Research Station. Pp. 44-59 in Sympo- sium on the Red-cockaded Woodpecker (R. L. Thompson, Ed.). Tallahassee, Florida, Bur. Sport Fish. Wildl., U.S. Dep. Interior and Tall Timbers Research Station. CHRISTENSEN, N.L. 1977. Fire regimes in southeast- ern ecosystems. Pp. 112-136 in Fire regimes and ecosystem properties (H. A. Mooney, T. M. Bon- nickson, N. L. Christensen, J. 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