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Jeffrey R. Walters - One of the best experts on this subject based on the ideXlab platform.
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How effective is the Safe Harbor program for the conservation of Red-cockaded Woodpeckers?
The Condor, 2018Co-Authors: Jennifer A. Smith, Kerry Brust, James Skelton, Jeffrey R. WaltersAbstract:ABSTRACT Land use restrictions imposed by the Endangered Species Act may create conflict, affecting conservation on private lands. In 1995, the Safe Harbor program (hereafter, ‘Safe Harbor’) was initiated to alleviate concerns of private landowners about conservation of imperiled species. The inaugural program targeted endangered Red-cockaded Woodpeckers (Picoides borealis; hereafter, ‘RCW') in the North Carolina Sandhills, USA. Landowners enrolled in the Safe Harbor select management actions to enhance habitat for existing populations, but incur no additional responsibilities for increases in populations. Despite the relevance for conservation, the benefits of Safe Harbor remain largely unknown. Here, we evaluate the effects of Safe Harbor on RCWs in the North Carolina Sandhills. Between 1980 and 2014, we monitored 55 RCW territories (30 Safe Harbor, 25 control). Following the initiation of Safe Harbor, the probability of territory abandonment on control properties increased by ∼14% over a 19-yr period, ...
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population models for social species lessons learned from models of red cockaded woodpeckers Picoides borealis
Ecological Applications, 2014Co-Authors: Sara L. Zeigler, Jeffrey R. WaltersAbstract: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.
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Population models for social species: lessons learned from models of Red‐cockaded Woodpeckers (Picoides borealis)
Ecological applications : a publication of the Ecological Society of America, 2014Co-Authors: Sara L. Zeigler, Jeffrey R. WaltersAbstract: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.
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A Minimally Invasive Method for Sampling Nest and Roost Cavities for Fungi: a Novel Approach to Identify the Fungi Associated with Cavity-Nesting Birds
Acta Ornithologica, 2014Co-Authors: Michelle A. Jusino, Daniel L. Lindner, John K. Cianchetti, Adam T. Grisé, Nicholas J. Brazee, Jeffrey R. WaltersAbstract:Abstract. Relationships among cavity-nesting birds, trees, and wood decay fungi pose interesting management challenges and research questions in many systems. Ornithologists need to understand the relationships between cavitynesting birds and fungi in order to understand the habitat requirements of these birds. Typically, researchers rely on fruiting body surveys to identify the fungal players in these relationships. Fruiting body surveys enable nondestructive sampling, but vastly underestimate fungal presence and diversity and may miss species of critical importance to cavity- nesting birds; thus new methods for such analyses are necessary. Here we present a novel technique to nondestructively sample the wood inside tree cavities, which produces samples that can be processed using DNA-based methods to identify fungi. We tested our method on Red-cockaded Woodpecker Picoides borealis excavations, half of which were from trees with Porodaedalea pini fruiting bodies. Using our new approach, we detected P. pi...
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Range-Wide Meta-Analysis of Red-Cockaded Woodpecker Foraging Habitat Suitability
2013Co-Authors: Ann E. Mckellar, Dylan C. Kesler, Robert J. Mitchell, David K Delancy, Jeffrey R. WaltersAbstract:Abstract : The work reported here describes the project Range-Wide Meta-Analysis of Red-Cockaded Woodpecker Foraging Habitat Suitability. This project was conducted under a cooperative agreement between the Engineer Research and Development Center - Construction Engineering Research Laboratory (ERDC-CERL) and The Curators of the University of Missouri. The primary objective of this project was to support conservation and recovery of a federally listed endangered avian species, the red-cockaded woodpecker (RCW: Picoides borealis). We aimed to identify the range of habitat conditions, as opposed to a single condition, that constitutes high-quality foraging habitat for RCWs, which will support recommendations for new RCW foraging habitat guidelines. This project has two components: (l) studies of the relationship between foraging habitat and RCW fitness across the species range, and (2) studies of foraging habitat selection by individual RCW groups on Eglin Air Force Base.
Susan C. Loeb - One of the best experts on this subject based on the ideXlab platform.
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Habitat and landscape correlates of southern flying squirrel use of red‐cockaded woodpecker clusters
Journal of Wildlife Management, 2012Co-Authors: Susan C. Loeb, Shawna L. Reid, Donald J. LipscombAbstract:Southern flying squirrels (Glaucomys volans) can have significant negative impacts on red-cockaded woodpecker (Picoides borealis) reproductive success and group size. Although direct control of southern flying squirrels may be necessary in small red-cockaded woodpecker populations (
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effects of southern flying squirrels glaucomys volans on red cockaded woodpecker Picoides borealis reproductive success
Animal Conservation, 1999Co-Authors: Kevin S Laves, Susan C. LoebAbstract:Anecdotal data gathered from many populations suggest that southern flying squirrel (SFS, Glaucomys volans ) use of the endangered red-cockaded woodpecker's (RCW, Picoides borealis ) nest and roost cavities may negatively affect RCW populations. We conducted a controlled experiment to determine the effects of SFSs on RCW reproductive success. During the 1994 and 1995 breeding seasons, SFSs were removed from 30 RCW clusters and 32 clusters served as controls. SFSs were the most frequently encountered occupants of RCW cavities and used 20–33% of RCW cavities in control and treatment clusters over both years. Treatment groups produced significantly more successful nests (≥ 1 fledgling) than control groups in 1994. In 1995 however, there was no difference in the number of successful nests. In both years, RCW groups nesting in treatment clusters produced significantly more fledglings than groups in control clusters in each of four experimental areas, averaging approximately 0.7 additional fledglings per nesting group. Loss of entire clutches or broods, possibly as a result of predation or abandonment, was a major factor limiting reproduction in control groups in 1994. In contrast, differences in partial brood loss appeared to be the cause of differential fledging success in 1995. Usurpation of RCW roost cavities by SFSs may have placed greater energetic demands on RCWs for cavity defence or thermoregulation, thus reducing energy available for reproduction. Our results show that SFS use of RCW cavities during the breeding season has a significant impact on RCWs and that management of RCW populations should include activities that either minimize SFS populations in RCW clusters or limit access of SFSs to RCW cavities.
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on red-cockaded woodpecker Picoides borealis reproductive success
1999Co-Authors: Kevin S Laves, Susan C. LoebAbstract:Anecdotal data gathered from many populations suggest that southern flying squirrel (SFS, Gluucomys volans) use of the endangered red-cockaded woodpecker’s (RCW, Picoides borealis) nest and roost cavities may negatively affect RCW populations. We conducted a controlled experiment to determine the effects of SFSs on RCW reproductive success. During the 1994 and 1995 breeding seasons, SFSs were removed from 30 RCW clusters and 32 clusters served as controls. SFSs were the most frequently encountered occupants of RCW cavities and used 20-33% of RCW cavities in control and treatment clusters over both years. Treatment groups produced significantly more successful nests (2 1 fledgling) than control groups in 1994. In 1995 however, there was no difference in the number of successful nests. In both years, RCW groups nesting in treatment clusters produced significantly more fledglings than groups in control clusters in each of four experimental areas, averaging approximately 0.7 additional fledglings per nesting group. Loss of entire clutches or broods, possibly as a result of predation or abandonment, was a major factor limiting reproduction in control groups in 1994. In contrast, differences in partial brood loss appeared to be the cause of differential fledging success in 1995. Usurpaiion of RCW roost cavities by SFSs may have placed greater energetic demands on RCWs for cavity defence or thermoregulation, thus reducing energy available for reproduction. Our results show that SFS use of RCW cavities during the breeding season has a significant impact on RCWs and that management of RCW populations should include activities that either minimize SFS populations in RCW clusters or 1i:mit access of SFSs to RCW cavities.
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Use and Selection of Red-Cockaded Woodpecker Cavities by Southern Flying Squirrels
Journal of Wildlife Management, 1993Co-Authors: Susan C. LoebAbstract:Southern flying squirrels (Glaucomys volans) may have a negative impact on red-cock woodpeckers (RCW's, Picoides borealis). Thus, I examined cavities excavated by RCW's in central Georgia during 4 breeding seasons to determine the extent of cavity use by southern flying squirrels and other competitors, and to determine whether flying squirrels select cavities on the basis of cavity or tree characteristics. Species other than RCW's occupied 18-25% of the RCW cavities over the 4 years. Flying squirrels used 10-21% of RCW cavities, whereas avian species other than RCW's used 4-8% of the cavities. Flying squirrels selected cavities primarily on the basis of cavity entrance size. Entrances to cavities used by flying squirrels were smaller (P ≤ 0.05) than entrances to unused cavities, and squirrels strongly preferred (P ≤ 0.05) cavities that had not been enlarged
Richard N. Conner - One of the best experts on this subject based on the ideXlab platform.
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Habitat Use and Avoidance by Foraging Red-Cockaded Woodpeckers in East Texas
Southeastern Naturalist, 2016Co-Authors: John N. Macey, D. Brent Burt, Daniel Saenz, Richard N. ConnerAbstract:Abstract Picoides borealis (Red-cockaded Woodpecker) is an endangered bird endemic to the Pinus (pine) ecosystems of the southeastern US. Mature pine savannahs with a minimal midstory and lush herbaceous groundcover represent high-quality habitat. This study examines the foraging-habitat patterns of Red-cockaded Woodpeckers in East Texas. We present a logistic regression model that best differentiates between foraged and non-foraged habitat. Increases in hardwood-midstory basal area have the greatest negative impact on the probability of Red-cockaded Woodpeckers selecting a habitat patch for foraging. Five additional variables negatively impact foraging probability: shrub height, diameter at breast height (DBH) of pine midstory, canopy closure, density of pine midstory, and density of hardwood midstory. Our model shows a high degree of accuracy as to the probability of habitat-patch selection for Red-cockaded Woodpeckers foraging in East Texas forests composed of different pine species.
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Report of the American Ornithologists ' Union Committee for the Conservation of the Red-cockaded Woodpecker
2015Co-Authors: David J. Lzgon, Richard N. Conner, Peter B. Stacey, Carl E. Bock, Curtis S. AdkissonAbstract:was to review the status of the federally endangered Red-cockaded Woodpecker (Picoides borealis), to evaluate the conservation and management practices impinging on the welfare of this species, and to further the A.O.U.'s interest in providing scientific advice and suggestions to managers of threatened and endangered species of birds. SUMMARY The Red-cockaded Woodpecker (Picoides borealis) in the southeastern United States has become endan-gered as a result of dependence on mature, open pine woodlands. This habitat, maintained in the past only by recurring fire, has become very scarce because of both the cutting of the pine forests for timber and the exclusion of fire. Moreover, modern timber man-agement practices focus almost exclusively on the production and harvest of young trees on private land and middle-aged trees on public land. Although Red
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Texas ratsnake predation on southern flying squirrels in red-cockaded woodpecker cavities
Southeastern Naturalist, 2009Co-Authors: D. Craig Rudolph, Richard R. Schaefer, Josh B. Pierce, Dan Saenz, Richard N. ConnerAbstract:Abstract Elaphe spp. (ratsnakes) are frequent predators on cavity-nesting birds and other vertebrates, including Glaucomys volons (Southern Flying Squirrels). They are known predators of Picoides borealis (Red-cockaded Woodpeckers), especially during the nestling phase. Picoides borealis cavities are frequently occupied by Southern Flying Squirrels, often several squirrels per cavity. Behavioral aspects of ratsnake predation on flying squirrels in woodpecker cavities is an important component required for a full understanding of the potentially complex interaction between Red-cockaded Woodpeckers, Southern Flying Squirrels, and ratsnakes. We induced previously captured Elaphe obsoleta (Texas Ratsnake) to climb boles of pine trees and gain access to Red-cockaded Woodpecker cavities known to contain Southern Flying Squirrels, and observed the resulting predatory interactions. Eight of nine ratsnakes successfully captured 14 of 22 Southern Flying Squirrels present in the cavities.
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Red-cockaded woodpecker foraging behavior
The Wilson Journal of Ornithology, 2007Co-Authors: D. Craig Rudolph, Richard R. Schaefer, Richard N. Conner, Nancy E. KoerthAbstract:Abstract We studied Red-cockaded Woodpeckers (Picoides borealis) to examine the effect of status and gender on foraging behavior. Foraging behavior of breeding pairs extended beyond separation by foraging height to include zones (bole, trunk in crown, primary limb, secondary limb) of the tree used and foraging methods (scaling, probing, excavating). Helper males and juvenile females maintained partial spatial separation from breeding adults. Helper males maintained spatial separation from breeding adults by exploiting limbs within tree crowns in both longleaf (Pinus palustris) and loblolly-shortleaf (P. taeda, P. echinata) pine forests, but also increased use of boles in loblolly-shortleaf pine in concert with reduced use of boles by adult females. Breeding males tended to forage less by scaling, probably due to the reduced proportion of foraging on boles of trees where scaling tends to predominate.
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Rainfall, El Niño, and Reproduction of Red-cockaded Woodpeckers
Southeastern Naturalist, 2005Co-Authors: Richard N. Conner, D. Craig Rudolph, Richard R. Schaefer, Daniel Saenz, James R. Mccormick, D. Brent BurtAbstract:Abstract This study examines the relationship between Red-cockaded Woodpecker (Picoides borealis Vieillot) reproduction and rainfall during May when group members are provisioning nestlings with food. Patterns of variation over a 4-year period of approximately 30 woodpecker groups suggested that the mean number of hatchling deaths was positively related to the amount of rainfall that occurred during May. During the same 4 years, the mean number of young fledged from nests appeared to be inversely related to May rainfall. Observations of nestling provisioning behavior during four breeding seasons indicate that group members slow down or stop feeding nestlings during periods of heavy rainfall. During a 20-year period, total May rainfall was related to the percentage of woodpecker groups producing fledgling-sized young in cavities (rs = −0.56, P = 0.0097) and the occurrence of El Nino events (rs = −0.50, P = 0.0347).
Karin Schiegg - One of the best experts on this subject based on the ideXlab platform.
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Inbreeding and experience affect response to climate change by endangered woodpeckers
Proceedings. Biological sciences, 2002Co-Authors: Karin Schiegg, Jeffrey R. Walters, Gilberto Pasinelli, Susan J. DanielsAbstract:In recent decades, female red-cockaded woodpeckers (Picoides borealis) have laid eggs increasingly earlier in response to a changing climate, as has been observed in several other bird species breeding at north temperate latitudes. Within each year, females that lay earlier are more productive than females that lay later. However, inexperienced females, experienced females who change mates and inbred birds have not adjusted to the changing climate by laying earlier, and have suffered reproductive costs as a result. Failure to respond to global climate change may be a further example of the reduced ability of inbred animals to respond to environmental challenges.
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Naturschutz in den USA: der Kokardenspecht Picoides borealis Vieill. und sein Lebensraum | Conservation biology in the USA: the redcockaded woodpecker (Picoides borealis Vieill.) and its habitat
Schweizerische Zeitschrift fur Forstwesen, 2002Co-Authors: Karin Schiegg, Gilberto PasinelliAbstract:The basis for the protection of species was already laid in the USA in 1973, aiming to consistently protect endangered species and their habitats and to prosecute violations of the law. Using the example of the highly endangered redcockaded woodpecker, which lives exclusively in the pine savannas of the south-east, we show the positive and negative consequences of the protection efforts over the past 30 years. Finally, we compare the possibilities of extensive species and biotope protection in Switzerland and discuss them within the framework of the Swiss legal regulations.
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naturschutz in den usa der kokardenspecht Picoides borealis vieill und sein lebensraum conservation biology in the usa the redcockaded woodpecker Picoides borealis vieill and its habitat
Schweizerische Zeitschrift Fur Forstwesen, 2002Co-Authors: Karin Schiegg, Gilberto PasinelliAbstract:The basis for the protection of species was already laid in the USA in 1973, aiming to consistently protect endangered species and their habitats and to prosecute violations of the law. Using the example of the highly endangered redcockaded woodpecker, which lives exclusively in the pine savannas of the south-east, we show the positive and negative consequences of the protection efforts over the past 30 years. Finally, we compare the possibilities of extensive species and biotope protection in Switzerland and discuss them within the framework of the Swiss legal regulations.
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The consequences of disrupted dispersal in fragmented red-cockaded woodpecker Picoides borealis populations
Journal of Animal Ecology, 2002Co-Authors: Karin Schiegg, Jeffrey R. Walters, Jeffery A. PriddyAbstract:Summary 1. Habitat fragmentation may adversely affect animal populations through several mechanisms. However, little is known about how the impacts of some of these mechanisms are manifested in altered dynamics of wild populations. 2. We used a spatially explicit individual-based simulation model to examine the potential effects of disrupted dispersal due to fragmentation on the population dynamics of the endangered, co-operatively breeding, red-cockaded woodpecker Picoides borealis . 3. We simulated population dynamics as a function of population size and spatial aggregation of territories. Dispersal success (but not mortality or fecundity) was an emergent property of model runs. In the model all female and some male fledglings dispersed in straight lines in random directions, and the remaining males stayed on their natal territories as helpers and competed for breeding vacancies in their immediate neighbourhood. 4. Population trend was tied to the higher dispersal success of both males and females in larger and less fragmented populations. Helpers were more successful than dispersing males. Male breeder recruitment depended entirely on helpers when populations were small (25 or 100 territories). 5. Declining populations were characterized by high emigration rates and both failure and delay in female recruitment. The large numbers of unpaired males resulted in lowered reproductive output at the population level and in the loss of territories. Populations of 25 territories were stable when territories were highly aggregated, despite high emigration rates. These results closely match empirical observations. 6. A number of co-operatively breeding species are endangered. The unusual dispersal behaviour of helpers may make such species sensitive to habitat fragmentation but also resilient to reductions in population size when territories are aggregated. Small populations of co-operative breeders may have considerable conservation value as a source of genetic diversity.
I. T. Moore - One of the best experts on this subject based on the ideXlab platform.
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Do stress hormones suppress helper reproduction in the cooperatively breeding red-cockaded woodpecker (Picoides borealis)?
Behavioral Ecology and Sociobiology, 2009Co-Authors: A. L. Malueg, J. R. Walters, I. T. MooreAbstract:In the cooperatively breeding red-cockaded woodpecker ( Picoides borealis ), male helpers are subordinate to male breeders and do not mate with females, even when unrelated to the breeding female within their group or through extra-group matings, yet exhibit reproductive hormone profiles similar to those of breeders. We investigated whether reproduction might be suppressed in helper males via high levels of the stress hormone corticosterone. We also examined effects of group size and season on corticosterone levels by comparing baseline and maximal plasma levels of corticosterone between helper males and breeding males, and among helper males and breeders of both sexes living in groups of different sizes throughout the reproductive cycle. We also measured plasma levels of estrogen, progesterone, and testosterone to examine other potential hormonal differences between helpers and breeders. Male status did not explain variation in any hormones; therefore, our data do not support the hypothesis that helper males are reproductively suppressed via corticosterone or the other hormones investigated. However, the presence of two or more helper males in a group tended to reduce baseline corticosterone in breeding and helper males, but not breeding females, suggesting that helper males reduce parental effort of other male group members. Seasonally, maximal corticosterone peaked during the nestling provisioning phase for breeding and helper males, but not breeder females, suggesting that males show an increased response to stressors posing a potential threat to survival of offspring.
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do stress hormones suppress helper reproduction in the cooperatively breeding red cockaded woodpecker Picoides borealis
Behavioral Ecology and Sociobiology, 2009Co-Authors: A. L. Malueg, Jeffrey R. Walters, I. T. MooreAbstract:In the cooperatively breeding red-cockaded woodpecker (Picoides borealis), male helpers are subordinate to male breeders and do not mate with females, even when unrelated to the breeding female within their group or through extra-group matings, yet exhibit reproductive hormone profiles similar to those of breeders. We investigated whether reproduction might be suppressed in helper males via high levels of the stress hormone corticosterone. We also examined effects of group size and season on corticosterone levels by comparing baseline and maximal plasma levels of corticosterone between helper males and breeding males, and among helper males and breeders of both sexes living in groups of different sizes throughout the reproductive cycle. We also measured plasma levels of estrogen, progesterone, and testosterone to examine other potential hormonal differences between helpers and breeders. Male status did not explain variation in any hormones; therefore, our data do not support the hypothesis that helper males are reproductively suppressed via corticosterone or the other hormones investigated. However, the presence of two or more helper males in a group tended to reduce baseline corticosterone in breeding and helper males, but not breeding females, suggesting that helper males reduce parental effort of other male group members. Seasonally, maximal corticosterone peaked during the nestling provisioning phase for breeding and helper males, but not breeder females, suggesting that males show an increased response to stressors posing a potential threat to survival of offspring.