Red-cockaded Woodpecker Populations Research Articles

Red-cockaded woodpecker habitat characteristics associated with partial brood loss in the Upper East Gulf Coastal Plain, USA

Some red-cockaded woodpecker (RCW) Dryobates borealis populations remain understudied. This is notable because management that incorporates population demographics and site characteristics may benefit RCW recovery. The Oakmulgee Ranger District of the Talladega National Forest (Alabama, USA) has no wiregrass Aristida stricta, small forest stand sizes, rolling topography, and contains an understudied RCW population. Our goal in the Oakmulgee was to characterize RCW habitat, possibly identify ways in which habitat differed from other regions, and estimate associations between habitat and reproductive output. We found that 70.2 and 92.5% of sampled stands met recovery standard thresholds for small and large pine basal area (BA) as defined in the United States Fish and Wildlife Service (USFWS) RCW Recovery Plan. While 74.6% of longleaf pine Pinus palustris-dominated stands met the threshold for overstory hardwood canopy composition, 60.0% of loblolly pine P. taeda-dominated stands did not. Few stands met the recommended percentage of herbaceous understory (19.8%) or recommended absence of hardwood midstory. A lower rate of partial brood loss was associated with a greater area of large pines (≥25.4 cm diameter at breast height; DBH), a smaller area of small pines (≥10 and <25.4 cm DBH), a larger area burned in the dormant season, and higher RCW density. In our models, hardwood overstory and midstory did not influence egg or hatchling production. Hardwoods in the Oakmulgee could contribute to unfavorable habitat, as indicated in the USFWS RCW Recovery Plan, as well as relate to variation in habitat across the RCW’s range. Regions of the RCW’s range are understudied, and limited staffing and funding impede advances in understanding and conservation.

A structured decision making analysis to increase a Red-cockaded Woodpecker population and balance stakeholder objectives for a National Forest

Longleaf pine (Pinus palustris) savanna is a biodiverse ecosystem native to the southeastern United States. Due to fire suppression and timber harvest, longleaf pine has declined to 3% of its original range. The extant forest provides habitat for many threatened and endangered species, including the endangered Red-cockaded Woodpecker (Picoides borealis; RCW), a cavity-nesting bird that co-evolved with fire-maintained forest, resulting in savanna-like old-growth forest as the bird’s preferred habitat. Our study site, the Oakmulgee Ranger District of the Talladega National Forest, harbors the largest RCW population in Alabama and is managed with an emphasis on RCW conservation. The United States Forest Service (USFS) also manages the Oakmulgee for uses such as wildlife conservation, recreation, and timber harvest. Despite efforts to restore RCW habitat and install artificial cavities in the Oakmulgee, the number of RCW groups has not exceeded 123, although the Recovery Plan objective is 394 groups. Our project was motivated by the USFS expressing interest in determining why the RCW population has not exceeded 123 groups. We proposed using structured decision making (SDM) with the USFS and other stakeholders to address this problem. Our goals were to explicitly define management objectives, build a Bayesian belief network with a model of how decision alternatives are believed to affect management objectives, and use a sensitivity analysis to determine the part of the model to which RCW population growth was most sensitive. Therefore, results from the analysis were expected to give insights into 1) ecological factors limiting RCW population growth, 2) how management can overcome these limits, plus 3) the relative expected ability of different decision alternatives to satisfy multiple objectives in addition to increasing RCW group number. We held four SDM workshops with representatives from the USFS, the Animal and Plant Health Inspection Service, the Longleaf Alliance, the Birmingham Audubon Society, and local residents. Stakeholder objectives consisted of maximizing the following: RCW group number, forest health, recreational enjoyment, community economic health, and aesthetics. Cavity insert installation had the greatest probability of increasing the number of RCW groups. The number of RCW groups was most affected by cavity availability, adult survival, reproductive output, food availability, and herbaceous understory. Prescribed burning was most likely to meet the combination of stakeholder objectives, followed by midstory removal. Our findings suggest that cavity installation efforts may need to be increased in the Oakmulgee to increase RCW group number. Also it could be beneficial to investigate how RCWs select cavity tree locations with the goal of increasing the chance that RCWs use artificial cavities to form new groups. The Bayesian belief network provided insights into factors limiting RCW population growth and how management can overcome these limits. The Bayesian belief network also can be used to prioritize management methods in the Oakmulgee given stakeholder objectives and time constraints.

Life history trait differences in isolated populations of the endangered Red-cockaded Woodpecker

Abstract Changes in life history traits can reveal adaptations to changing environments. Red-cockaded Woodpeckers (Picoides borealis) are cooperative breeders that have specific reproductive habitat needs. We examined three separate sites in the southeastern United States to see how life history traits differed among isolated populations of Red-cockaded Woodpeckers from 1980 to 2013. We examined the life history traits group size, partial brood loss, number of fledglings, lay date, clutch size, and lifespan. Traits differed among sites, suggesting that populations were adapted to local conditions and different life history trade-offs were important under different environmental conditions at each site. At the two coastal sites in Florida and North Carolina, the family group sizes, lifespans, and partial brood loss were higher when compared to the inland site in North Carolina. Clutch size and number fledged were higher at the two northernmost sites when compared to the southern site. Identifying the differences in life history traits can allow more specific and effective management practices.

Population models for social species: lessons learned from models of Red‐cockaded Woodpeckers (Picoides borealis).

Behavior can have major impacts on the population dynamics of social species and should be incorporated into demographic models to realistically evaluate population trends and extinction risk. We compared the predictions of a stage- and age-based matrix model, an individual-based model (IBM, developed in the program Vortex), and a spatially explicit individual-based model (SEPM) with the actual dynamics of a population of Red-cockaded Woodpeckers (RCW; Picoides borealis) in the Sandhills of North Carolina, USA. Predictions, including population size, composition, and growth rate, differed the most from actual population characteristics for models that did not incorporate social structure. The SEPM most closely predicted actual population dynamics, underestimating the population by 2.3%. This model, specifically developed to simulate RCW population dynamics, contains many of the features that we assert are important for adequately incorporating social behavior into demographic and population modeling. These features include the ability to (1) differentiate individuals based on their stage class, (2) capture the dynamics of the population at both the individual and group level, (3) incorporate the positive or negative effects of subdominants, (4) include environmental and demographic stochasticity, and (5) capture dispersal and other spatial factors. The RCW SEPM, although currently species-specific, provides a strong blueprint for how population models for social species could be constructed in the future when data allow.

Geographic variation in fitness and foraging habitat quality in an endangered bird

Models are important tools for conservation, but the usefulness of any given model for decision-making depends on its accuracy and precision. Few models designed for conservation purposes are validated with real-world data, and such models are even less likely to be revisited and improved with post-implementation results. We test the performance of a model frequently used and heavily relied-upon for the management of the endangered red-cockaded woodpecker (Picoides borealis). The RCW Foraging Matrix Application incorporates spatially-explicit forest stand data and woodpecker territory locations to produce quantitative assessments of foraging habitat quality. Model parameters were based on expert opinion and research performed on several key populations at a time when range-wide habitat quality was relatively poor. Since the model’s inception, many red-cockaded woodpecker populations have been monitored intensely in restored habitat, providing an opportunity to evaluate model performance range-wide. We assessed the relationship of habitat quality, as measured by the RCW Matrix Application, to group size and fledgling production from populations across the species range in the southeastern United States. We also evaluated foraging habitat quality directly by relating woodpecker fitness components to foraging habitat metrics through regression tree analyses. Results showed that some, but not all, of the habitat metrics included in the RCW Matrix Application were consistently related to fitness components range-wide, but threshold values for these habitat metrics identified by regression tree analyses were site-specific rather than universal. Our findings indicate opportunities for improving on “one-size-fits-all” range-wide models with analyses of additional locally-relevant foraging habitat metrics.

Nest Site Selection and Reproductive Success of Red-cockaded Woodpeckers in Ocala National Forest

Red-cockaded woodpeckers (Picoides borealis) in the Ocala National Forest are located near the southern edge of the species' geographic range in a region that contains the largest contiguous area of sand pine scrub habitat endemic to Florida. We examined nest site selection and nest success of the species in this unique region to determine which habitat characteristics and management activities contribute most to woodpecker productivity. We used data from a single year (2010) to assess the relative importance of forest stand features, landscape features, management activities, and spatial characteristics affecting social behavior of the birds and found fire management practices played the largest role in habitat selection, while understory characteristics were most important to reproductive success. We also used data spanning an entire decade (2001 to 2010) to assess the relative importance of landscape features, management activities, spatial characteristics affecting social behavior of the birds, and environmental factors in habitat selection and productivity. We again found the number of fire events was most influential to habitat selection, whereas the location of clusters relative to the sand pine ecotone was most influential to reproductive success. Results highlight the well-known importance of using fire to maintain quality habitat for the species but also suggest some unique aspects pertinent to managing this southern population of red-cockaded woodpeckers.

Quantifying Purported Competition with Individual- and Population-Level Metrics

Competitive species interactions may contribute to population declines. Purportedly, Red-bellied Woodpeckers (Melanerpes carolinus), a common species, and Red-cockaded Woodpeckers (Picoides borealis), an endangered species, compete for roosting and nesting cavities in living pine trees. To determine whether behavioral interactions measured at the individual level manifest themselves at the population level, we conducted field experiments designed to test whether the presence of Red-bellied Woodpeckers resulted in a decrease in fitness to Red-cockaded Woodpeckers. As part of a 4-year study examining the nature of interspecific interactions in two populations of Red-cockaded Woodpeckers (one stable, the Apalachicola Ranger District; one declining, the Wakulla Ranger District) in the Apalachicola National Forest, Florida, we conducted a set of Red-bellied Woodpecker removal experiments. Paradoxically, following the removal of Red-bellied Woodpeckers, we observed decreases in Red-cockaded Woodpecker group size, proportion of nests that were successful, and proportion of individuals remaining on territories. Removal of Red-bellied Woodpeckers may have exaggerated the immigration rate of Red-bellied Woodpeckers to Red-cockaded Woodpecker territories. The Red-cockaded Woodpeckers in the Apalachicola Ranger District likely can withstand pressure from immigrating Red-bellied Woodpeckers given that their population has remained relatively stable despite the presence of Red-bellied Woodpeckers. A major factor of population persistence in the Wakulla Ranger District was the high turnover rate of adult female Red-cockaded Woodpeckers, a phenomenon that was exacerbated by removal of Red-bellied Woodpeckers. Relying solely on observations of apparently competitive interactions between individuals may not necessarily provide information about population-level outcomes. Paradoxically, removing species that appear to be competitors may harm species of concern.

Kleptoparasitism of a Red-Cockaded Woodpecker (Picoides borealis) Nest Cavity by a Red-Bellied Woodpecker (Melanerpes carolinus)

Abstract We report the kleptoparasitism of a Picoides borealis (Red-cockaded Woodpecker) cavity by a Melanerpes carolinus (Red-bellied Woodpecker). We believe this is the first video documenting kleptoparasitism of a Red-cockaded Woodpecker nest by a male Red-bellied Woodpecker in which both a nestling and an attending adult Red-cockaded Woodpecker adult were forcibly ejected. The Red-bellied Woodpecker was resolute in its attempt to usurp the nest, reaching into the cavity over 2000 times in an attempt to evict the cavity occupants. The male Red-bellied Woodpecker and his mate took over the cavity soon after. Adult Red-cockaded Woodpeckers continued to visit their nest cavity during diurnal hours for 2 days post-kleptoparasitism. It is important that resource managers incorporate proactive management techniques to lessen the impact of interspecific competition for cavities, especially in smaller or fragmented Red-cockaded Woodpecker populations.

Competitive Positioning as an Indicator of Nestling Survival in Red-cockaded Woodpeckers

Nestling behavior in five populations of red-cockaded woodpeckers (Picoides borealis) in peninsula Florida from 1997–2003 and 2007 revealed novel mechanisms and behavioral positioning of crossed, disproportionately long necks in all nestlings (Stage I, 10–17 days of age). Nest observations in Stage I showed that the crossed neck behavior occurred in all broods of two or more, and facilitated dominant nestlings to beg sooner, reach higher, and to knock aside their smaller siblings, effectively controlling the central point below the nest cavity entrance. Stage II and III nestlings (11–17 and >18 days, respectively) were generally satiate in the cavity bottom on most occasions. Compared to satiate nests, those with elevated levels of aggressive behavior fledged significantly fewer young. Aggressive positioning behavior, fighting, and pecking occurred in Stage I...

Variation in Resin-well Construction as an Indicator of Predation Load and Breeder Experience in Red-cockaded Woodpecker Populations

The pine forest of the southeastern coastal plain supports a rich assemblage of cavity nesting birds. Unlike some regions, most primary and secondary cavity nesters experience high rates of nest predation. Rat snakes (Elaphe spp.) are proficient tree climbers and are well-documented nest predators throughout the red-cockaded woodpecker's (Picoides borealis) range. Nesting success of this species, however, is relatively high. This woodpecker is well-known for excavating cavities in living pine trees as well as excavating moderate to small holes or resin wells above and below its cavities, and scaling loose bark from around them. These behaviors create a surface around the cavity entrance that is difficult for snakes to climb. Despite these protective behaviors, snakes successfully depredate some nests. This suggests that variation may exist in individual woodpecker investment in cavity protective behaviors. To explore the usefulness of resin-well construction on cavity trees as an indicator of predation an...

Inbreeding in red-cockaded woodpeckers: Effects of natal dispersal distance and territory location

Inbreeding depression constitutes a significant threat to the viability of small populations. In addition to small size and isolation of populations, short distance dispersal may elevate risk of inbreeding, but empirical evidence is scarce. Inbreeding depression has been demonstrated in the highly endangered red-cockaded woodpecker Picoides borealis. It has been suggested that conservation efforts to support extant populations should aim at spatially aggregating territories to enhance dispersal success. This however may aggravate inbreeding risk because distance between territories and hence dispersal distances become short. We analysed empirical data from a long-term study of the demography of the red-cockaded woodpecker and found that inbreeding risk varied inversely with natal dispersal distance of the mother. Using an individual-based, spatially explicit population model that incorporates simulations of environmental and demographic stochasticity and an empirically derived, species-specific estimate of inbreeding costs, we demonstrated that inbreeding depression significantly elevated extinction risk in this species. On the other hand, even though dispersal distances in populations with spatially aggregated territories were shorter and the proportion of inbred individuals was higher than in other populations of the same size, such populations were still more persistent. Despite the overall adverse effect of inbreeding depression on viability of red-cockaded woodpecker populations, lowering interterritorial distances can be viewed as a valuable conservation tool. Given the small size and isolated location of most extant red-cockaded woodpecker populations however, our findings suggest that inbreeding depression represents a significant threat to the survival of this species.

Evaluating Red-cockaded Woodpeckers for Exposure to West Nile Virus and Blood Parasites

A marked decline in the Picoides borealis (Red-cockaded Woodpecker (RCW)) population at Noxubee National Wildlife Refuge, MS, was observed in 2002. Demographic changes—including absence of hatch-year birds, decreases in size of known groups, and loss of known groups—were identified during annual fall surveys and are uncharacteristic of RCW populations. In 2003, a serosurvey of 28 adult RCWs was conducted to investigate the presence of West Nile virus (WNV) exposure in the population, possibly providing insight into whether WNV may have been responsible for this decline. Blood smears were also examined from these birds for blood parasites. We found no evidence of West Nile virus exposure or blood parasites in any of the RCWs sampled. Further monitoring of the RCW population and WNV activity in other species at Noxubee NWR is recommended to further evaluate the potential role of WNV and blood parasites in their decline.

RED-COCKADED WOODPECKER FORAGING BEHAVIOR IN RELATION TO MIDSTORY VEGETATION

Red-cockaded Woodpeckers (Picoides borealis) nest and forage in pine-dominated forests. Research indicates that substantial hardwood midstory encroachment is detrimental to Red-cockaded Woodpecker populations, although the exact mechanisms are unknown. We examined foraging behavior in relation to midstory between August 1989 and February 1990. Red-cockaded Woodpeckers foraged at greater heights in areas of taller and denser midstory in the loblolly-shortleaf pine (Pinus taeda and P. echinata, respectively) habitat, but not in longleaf pine (P. palustris) habitat with less-developed midstory vegetation than typical of loblolly-shortleaf pine habitat. In addition, Red-cockaded Woodpeckers concentrated foraging activities in or adjacent to forest stands or openings with reduced midstory vegetation. Overall, Red-cockaded Woodpeckers foraged disproportionately at heights and sites that minimized their exposure to dense midstory conditions. These results suggest that ecosystem management, preferably using prescribed fire, that reduces midstory vegetation will improve foraging habitat for Red-cockaded Woodpeckers.

POPULATION VIABILITY ANALYSIS FOR RED-COCKADED WOODPECKERS USING AN INDIVIDUAL-BASED MODEL

Red-cockaded Woodpeckers (Picoides borealis) are distributed in the southeastern United States among closed populations whose maximum size is limited. Previous population viability analyses for this species have been confined to examination of threats posed by catastrophes and loss of genetic variability, because of the lack of demographic models that incorporate the extreme spatial constraints on dispersal that characterize this species. We used a spatially explicit, individual-based simulation model to assess the vulnerability of Red-cockaded Woodpecker populations to demographic and environmental stochasticity. Vulnerability to these threats was relatively low, because the presence of a substantial nonbreeding class (i.e., helpers) ameliorated the impact of stochastic variation in mortality and reproduction on the size of the breeding population. Because dispersal of helpers is spatially restricted, this effect was most pronounced when territories were aggregated or at high densities. Populations of 250 and 500 territories were stable regardless of the level of territory aggregation at the densities examined, whereas populations of 25, 49, and 100 territories ranged from rapidly declining to stable, depending on territory density and level of aggregation. Techniques that enable managers to maintain existing territories and create new ones are well established for this species. Thus managers may reasonably expect to maintain even small populations of Red-cockaded Woodpeckers by increasing the density, level of aggregation, and number of territories.

Influence of the spatial pattern of conserved lands on the persistence of a large population of red-cockaded woodpeckers

Spatial configuration of habitats can affect chances of survival for many rare species, especially those with low dispersal rates or large area requirements. The red-cockaded woodpecker (Picoides borealis) disperses relatively short distances and also requires large blocks of habitat — characteristics that make its populations especially sensitive to the distribution of its habitat across a region. We created conservation scenarios for a large population of red-cockaded woodpeckers based on acquisition of conservation easements on different properties, and we then estimated the probability of long-term persistence using Geographic Information System technology and a stochastic demographic model. We considered four broad conservation scenarios: (1) conservation of only those properties that currently have easements (Status quo); (2) random acquisition of additional conservation properties (Random); (3) strategic acquisition of additional conservation properties (Strategic); and (4) all properties that have red-cockaded woodpeckers gain protection (Total Protection). The data used in the analyses come from the sixth-largest population (ca. 180 groups), which occurs exclusively on private lands in the Red Hills region of north Florida and south Georgia. Chances of survival exclusively on existing easements were low unless large-scale improvements in habitat quality were realized. Easements acquired in random order also did not effectively conserve the large aggregations of active territories important to population persistence. Even when up to 20,000 ha of new easements were added randomly, densities and distributions of active territories generally remained critically over-dispersed. Random acquisition of easements did not approximate the additions of habitat based on biological criteria until 30,000 ha were added and an average of 60% of all clusters was conserved, and even then neighborhood sizes were roughly half the sizes of neighborhoods produced using biological criteria. Alternatively, use of biological criteria to select key properties with a total area <10,000 ha better approximated several spatial characteristics associated with population persistence. Overall, scenarios that provided the highest likelihood of long-term survival conserved core properties and expanded the population on existing easements through habitat improvement and intensive management techniques. This will require ca. 17,000 ha in new easements. We also suggest that management be used to augment populations on existing easements, particularly peripheral regions where populations of ca. 25 territories might eventually be established.

Translocation of Red-Cockaded Woodpeckers by Reciprocal Fostering of Nestlings

The endangered red-cockaded woodpecker (Picoides borealis), a nonmigratory, cooperatively breeding species limited to the older-growth pine forests of the southeastern United States, requires living pine trees for cavity excavation. Since the 1950s, alteration and destruction of critical woodpecker habitat have caused a decline in red-cockaded woodpecker populations. The red-cockaded woodpecker now exists mostly in small, scattered populations whose respective members have little opportunity to interbreed. In general, as populations become smaller and more isolated, the frequency of inbreeding increases and genetic diversity and population viability may decrease. The introduction of unrelated individuals into disjunct red-cockaded woodpecker populations may reduce inbreeding, maintain genetic variability, and reduce local extinction. We developed a technique for selecting red-cockaded woodpecker nestlings and transferring them into the nests of unrelated conspecifics. For each translocation, we paired nests by age and exchanged 1 nestling from each, so that 2 introductions were made with 1 reciprocal translocation event. Nest visitation by the parents and fledging success of nestlings were monitored. Fostered nestlings were accepted by their new parents, and the rate of successful fledging by fostered nestlings was not different from that of nonfostered control nestlings. We concluded that reciprocal intraspecific fostering of similarly aged nestlings can be used safely and effectively to translocate red-cockaded woodpeckers and may have advantages over the translocation of adults and juveniles under certain conditions.

A HISTORICAL VIEW OF RED-COCKADED WOODPECKER HABITAT ON FORT POLK, LOUISIANA

The Red-cockaded Woodpecker population in Louisiana suffered massive habitat loss in the early 1900s resulting from large-scale clearcutting. We examined post-harvest aerial photographs of Fort Polk, Louisiana, from the 1930s to determine the extent of remnant forest and compared these remnants to current Red-cockaded Woodpecker clusters. Additionally, descriptive data—age, dbh, location—were gathered for all cavity trees within our study areas. Analysis of the photographs made it clear that the harvesting of the 1920s did not completely denude the landscape: trees remained in dense stands along streams and in scattered groups on some upland sites. These remnant trees corresponded to current woodpecker nest sites: on the two study areas, 84% and 100% of woodpecker clusters in 1997 were located on sites that contained trees from the 1930s. Over half of the current cavity trees on one site and over three quarters on the other site are remnant trees which survived the clearcutting. Those trees are the foundation of the habitat available to the Red-cockaded Woodpecker population on the sites today, and based on the nesting habits of this bird, the remnants probably provided the needed habitat to support a continuous or near-continuous Red-cockaded woodpecker population in the area through the post-harvest recovery period and up to the present day.

An analysis of reciprocal exchange of helping behavior in the red-cockaded woodpecker ( Picoides borealis )

We examine the frequency of reciprocal exchanges of helping behavior in three red-cockaded woodpecker populations to determine if such exchanges might constitute a significant fitness benefit of helping. Specifically, we determine how often helpers, once they become breeders, are assisted by young they previously helped raise. The estimated frequencies of reciprocal exchange of helping based on survival and status transition probabilities are low (2%). Observed frequencies of reciprocity are significantly higher than estimated frequencies in two of the three populations studied, suggesting that male fledglings more often remain on their natal territory as helpers if another helper is already present. High rates of retention of young males as helpers on high-quality territories or preferential helping of kin, as well as preferential helping of former care-givers, might explain this result. When the analysis is restricted to helpers unrelated to the young they help raise, which controls for preferential helping of kin and largely eliminates effects of territory quality, empirical estimates of the frequency of reciprocity do not differ from estimates calculated from population demography. We conclude that young males do not preferentially help former care-givers and that reciprocal exchange of help is not an important factor in the evolution of helping behavior in the red-cockaded woodpecker. In this species, all known benefits of helping behavior are indirect (i.e., derived through kin selection ) rather than direct. We discuss the occurrence of unrelated helpers in this context.

Functional heterogeneity of forest landscapes and the distribution and abundance of the red-cockaded woodpecker

Red-cockaded woodpecker (RCW, Picoides borealis) populations are greatly affected by the fragmentation of forest habitat through its effect on the dispersal of individuals between active clusters and other areas of the suitable habitat. In order to assess the suitability of a given landscape structure for the maintenance and expansion of RCW populations, land managers need an index that correlates with the bird's awareness of that structure. Rather than assuming that common landscape metrics provide the necessary information, we applied an index of functional heterogeneity to a GIS coverage for the western portion of the Sam Houston National Forest (SHNF) in east Texas, using two observation scales. In contrast to measured heterogeneity, functional heterogeneity incorporates the RCW response to forest structure. The GIS coverage included information on habitat suitability and RCW cluster distribution and size. The analyses indicated that the presence of cavity trees is the most important factor for RCW population maintenance and that fragmentation of the foraging habitat has much less impact. The analyses also indicated that many areas that are currently of high functional importance for the RCW are effectively isolated from one another. This second result has significant implications for the dispersal of individuals between areas of high functionality and thus also the maintenance of the RCW in this forest. The functional heterogeneity analyses can also be used to examine the trade offs involved in managing the multiple wildlife species simultaneously and for examining the effects of various harvesting regimes through time.

Preemptive Habitat Destruction Under the Endangered Species Act

This paper examines the extent to which landowners have preemptively destroyed endangered species' habitats in order to avoid potential landuse regulations prescribed under the Endangered Species Act (ESA). Under the ESA it is not only illegal to take (kill) an endangered species, but it is also illegal to damage their habitat. Our application is to red-cockaded woodpeckers (RCWs) in the forests of North Carolina. RCWs are an endangered species that live in old growth pine forests throughout the Southeast. Our primary hypothesis is that the closer a landowner is to known populations of RCWs, the more likely the landowner will take action to destroy the habitat for RCWs, primarily by prematurely cutting their pine forest. By preventing the establishment of an old growth pine stand, the landowner can insure that RCWs do not inhabit their land and avoid ESA regulations that limit or prohibit timber harvest activity. Two empirical questions are addressed: How does the potential for ESA regulation affect the harvest probability of a particular forest plot? How does the potential for ESA regulation affect the age at which a forest will be harvested? Data on over 1,000 individual forest plots from the U.S. Forest Service's Forest Inventory and Analysis (FIA) and a 1997-98 North Carolina State University (NCSU) survey of over 400 landowners are used to test predictions about the probability of harvest and the age of timber when it is harvested. The location of RCW populations is used to construct various measures of the probability that a forest plot will become inhabited by RCWs and thus subject to ESA restrictions on land use. Probit regressions estimate the probability that a plot is harvested and OLS regressions - corrected for harvest selection bias - estimate the age at which a plot is harvested. In all our estimates we find that increases in the proximity of a plot to RCWs increases the probability that the plot will be harvested and decreases the age at which the forest is harvested. These findings indicate that the ESA, at least for RCWs in North Carolina, actually reduces the amount of endangered species habitat.