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Abstract: The Dollarbird (Eurystomus orientalis) is a secondary cavity-nesting bird that is distributed quite locally in Japan. We carried out extensive surveys across Okayama Prefecture to estimate the number of [...]

Crown-burned pine forests are an important breeding habitat for many cavity-nesting birds, and can serve as a source habitat for some woodpecker species. However, it is unclear if this function continues with postburn succession as predators recolonize burned habitats and snag density declines. Lewis's Woodpeckers (Melanerpes lewis) are considered 'burn specialists' and are a species of conservation concern. We monitored Lewis's Woodpeckers nesting in ponderosa pine (Pinus ponderosa) forests to determine the source or sink function of old-burn habitats in the Black Hills of South Dakota (study units burned in 1988 and 1991): concurrently, we examined avian and mammalian predator communities within burned and unburned areas. Between 2002 and 2005 we found 55 Lewis's Woodpecker nests, 51 of which were successful. Using adult and juvenile mortality rates for other melanerpine species taken from the literature, we determined that the old-burn habitats we sampled were acting as sources for Lewis's Woodpeckers. Point counts and tracking tube surveys suggested that both avian and mammalian predators had successfully recolonized these old-burn habitats, as both groups were common in old burns and in unburned forests. The unusually high nesting success of Lewis's Woodpeckers in the Black Hills is likely due to the absence of some common nest predators. While the high success rates might continue, we suggest that the overall contribution of young to the region from these burned sites will decline as suitable habitat components (such as snags) decline with the continuation of postfire succession. Key words: Black Hills, cavity nesting, Melanerpes lewis, ponderosa pine, predation, wildfire. Los bosques de coniferas cuyas copas de los arboles han sido quemadas son un habitat importante para muchas especies de aves que anidan en cavidades y tambien pueden servir como un habitat fuente para algunas especies de carpinteros. Sin embargo, no esta claro siesta funcion continua con la sucesion post-quema cuando los depredadores comienzan a recolonizar el habitat quemado y la densidad de arboles muertos en pie disminuye. El carpintero Mehmerpes lewis es considerado especialista de habitats quemados y es una especie en estado de conservacion vulnerable. Monitoreamos poblaciones de M. lewis que nidifican en pinos de la especie Pinus ponderosa en las montanas Black Hills en Dakota de Sur para determinar la funcion de fuente o sumidero de habitats quemados en el pasado (areas de estudio quemadas en 1988 y 1991), y para examinar las comunidades de depredadores (aves y mamiferos) en las areas quemadas. Entre los anos 2002 y 2005 encontramos 55 nidos de M. lewis, 51 de los cuales fueron exitosos. Utilizando tasas de mortalidad de adultos y juveniles de otras especies del grupo melanerpine provenientes de la literatura, determinamos que los habitats quemados en el pasado actuaron como habitat fuente para M. lewis. Conteos en puntos y muestreos utilizando tubos de rastreo sugirieron que tanto los depredadores aviares como mamiferos habian colonizado exitosamente estos habitats quemados, ya que ambos grupos fueron abundantes en bosques quemados y no quemados. El exito de nidificacion inusualmente alto de M. lewis en nuestra area de estudio se debe probablemente a la ausencia de algunos depredadores de nido comunes. Si bien las tasas de exito de nidificacion altas pueden continuar, sugerimos que la contribucion regional de juveniles desde estas areas quemadas disminuira conforme los componentes apropiados del habitat (como los arboles muertos en pie) disminuyan con la progresion del proceso de sucesion post-quema.

There have been several studies on egg composition in birds, but none on woodpeckers. Woodpeckers (Picidae) have among the smallest eggs relative to their body size of any bird. I dissected Northern Flicker (Colaptes auratus) eggs into shell, yolk, and albumen components, and determined the lipid content of the yolk. The proportional size of the yolk in flicker eggs (16%) was among the smallest described for any bird. However, the yolk contained a similar amount of lipid (58%) as the yolks of other altricial species. The overall energy density in flicker eggs, 3.8 kJ [g.sup.-1], was also among the lowest reported in birds. The relative size of the yolk tended toward negative allometry with increasing total egg mass while the amount of albumen showed positive allometry, but the confidence intervals for the regression slopes showed that isometry of these components could not be excluded. These results demonstrate that flicker eggs contain relatively little energy and, compared to other species, eggs may be relatively cheap for flicker females to produce. Key words: egg composition, Picidae, woodpecker. Existen varios estudios sobre la composicion de los huevos en las aves, pero ninguno en pajaros carpinteros (Picidae). Los carpinteros presentan algunos de los huevos mas pequenos de las ayes en relacion con el tamano de sus cuerpos. Disecte huevos de Colaptes auratus en sus componentes de cascara, yema y albumen, y determine el contenido de lipidos de la yema. El tamano proporcional de la yema en los huevos de C auratus (16%) fue uno de los mas pequenos descrito para las ayes. Sin embargo, la yema contuvo una cantidad similar de lipidos (58%) que la yema de otras especies altriciales. La densidad total de energia en los huevos de C. auratus fue de 3.8 kJ [g.sup.-1] y estuvo tambian entre las mas bajas conocidas para las ayes. El tamano relativo de la yema tendio a una alometria negativa con el incremento de la masa total del huevo, mientras que la cantidad de albumen mostro una alometria positiva, pero los intervalos de confianza para las pendientes de las regresiones mostraron que no puede excluirse una relacion isometrica para estos componentes. Estos resultados demuestran que los huevos de C. auratus contienen relativamente poca energia y que, en comparacion con otras especies, producir huevos puede ser relativamente barato para las hembras de C. auratus.

Red-headed Woodpecker (Melanerpes erythrocephalus) populations are declining at a continental scale, yet little is known about their nest-site selection and reproduction within burned forests. We measured reproductive parameters and nest-site characteristics at 17 Red-headed Woodpecker nests and 17 random sites between 2001 and 2004 in the Black Hills, South Dakota. The average date the first egg was laid was 17 June, and the average clutch size was 5.4 [+ or -] 0.4. The daily nest survival rate averaged 0.98 (overall nest success = 47%), and predation was the major cause of nest failure. Red-headed Woodpecker nests occurred farther from grassland edges in large diameter snags within severely burned quaking aspen (Populus tremuloides) stands. High-severity tire within these aspen stands resulted in a combination of snag and understory characteristics that differed from the surrounding pine forest matrix. Interactions between cover type and burn severity may have important ecological consequences for Red-headed Woodpeckers in a mixed conifer forest. Key words: aspen, Black Hills, burn severity, habitat selection, Melanerpes erythrocephalus, Populus tremuloides, Red-headed Woodpecker. Las poblaciones de Melanerpes erythrocephalus estan disminuyendo a escala continental y sin embargo se conoce poco sobre la seleccion de sitios de nidificacion y la reproduccion de esta especie en bosques incendiados. Medimos parametros reproductivos y caracteristicas de los sitios de nidificacion en 17 nidos de M. erythrocephalus yen 17 sitios aleatorios entre los anos 2001 y 2004 en Black Hills, Dakota del Sur. La fecha promedio en que fue puesto el primer huevo fue el 17 de junio y el tamano promedio de la nidada fue de 5.4 [+ or -] 0.4. La tasa diaria de supervivencia del nido promedio 0.98 (exito global del nido = 47%), y la depredacion rue la principal causa de fracaso del nido. Los nidos de M. erythrocephalus se ubicaron alejados de los bordes con los pastizales, en arboles muertos en pie de gran diametro, dentro de bosques severamente quemados de Populus tremuloides. La incidencia de fuegos muy severos al interior de estos bosques de alamo genero una combinacion de caracteristicas de los arboles muertos en pie y del sotobosque que difirieron de la matriz periferica de bosque de pino. Las interacciones entre el tipo de cobertura y la severidad del incendio pueden tener consecuencias ecologicas importantes para M. erythrocephalus en los boques mixtos de coniferas.

We investigated nest-hole excavation by the Red-naped Sapsucker (Syphrapicus nuchalis) in aspen (Populus tremuloides) woodlands in western Colorado. Sapsuckers excavate nest cavities primarily in aspens infected with a heartwood rot fungus (Phellinus tremulae), which softens the heartwood of infected trees. We assessed the interior condition of fungus-infected aspen trunks by extracting wood samples with an increment corer to determine whether sapsuckers chose nest-hole locations based on the extent of healthy sapwood remaining. Comparing fungus-infected trees with and without cavities, cavity-bearing trees had thinner healthy sapwood. The depth of healthy sapwood also varied with compass direction, being thinnest on the south sides of fungus-infected aspens. Cavity entrance orientations were significantly biased to the south-southeast, corresponding with the directional bias in heartwood rot. These results suggest that the depth of healthy sapwood, and hence excavation effort, may be important in determining nest hole location for the Red-naped Sapsucker. Key words: cavity-nesting birds, heartwood fungus, nest-site selection, Phellinus tremulae, Populus tremuloides, Red-naped Sapsucker, Syphrapicus nuchalis. Investigamos la excavacion de cavidades de nidificacion por parte de Syphrapicus nuchalis en bosques de Populus tremuloides en el oeste de Colorado. Esta especie excava las cavidades principalmente en arboles infectados con el hongo Phellinus tremulae, el cual ablanda la madera. Evaluamos la condicion interna de los troncos de los arboles infectados mediante la extraccion de muestras de madera con un barreno de incremento para determinar si las aves eligen la localization de las cavidades basadas en la magnitud de restos de madera saludable. Comparando los arboles infectados con hongos con y sin cavidades, los arboles que presentaron cavidades tuvieron una madera saludable mas delgada. La profundidad de la madera saludable tambien vario con la orientacion cardinal, siendo mas delgada en las caras sur de los arboles infectados. La orientacion de la entrada de las cavidades estuvo significativamente sesgada hacia el sur-sureste, correspondiendo con el sesgo direccional del hongo. Estos resultados sugieren que la profundidad de la madera saludable, y por ende el esfuerzo de excavacion, pueden ser importantes para determinar la localizacion de las cavidades de nidificacion en S. nuchalis.

This study uses mitochondrial DNA (mtDNA) to examine the phylogeography of the White-headed Woodpecker (Picoides albolarvatus), one of the least-studied woodpeckers in North America. A mismatch distribution and calculation of Tajima's D indicate that the overall phylogeographic history of the species is characterized by a recent range expansion that probably occurred after the start of the Pleistocene. In addition, a nested clade phylogeographic analysis indicates that additional processes such as allopatric fragmentation and restricted gene flow have influenced the evolutionary history of this species. Traditionally, the White-headed Woodpecker has been split into two subspecies whose distributions meet in the northern part of the Transverse Ranges in California. The two subspecies differ morphologically, with the southern subspecies having a larger bill in proportion to its body size than the northern subspecies. Geographical variation in mtDNA is concordant with a division at the Transverse Ranges that corresponds to the morphological variation seen between the two subspecies. An analysis of molecular variance indicates that 27% of the genetic variation results from differences between the northern and southern subspecies. Furthermore, birds in the northern part of the range differ from those in the southern part of the range by at least one base substitution. These results agree with the hypothesis that the larger bill of the southern subspecies is the result of recent local adaptation to feeding on the large cones of Coulter pines (Pinus coulteri). Key words: bill morphology, evolutionarily significant unit, nested clade phylogeographic analysis, phylogeography, Picoides albolarvatus, subspecies, White-headed Woodpecker. Este estudio utiliza ADN mitocondrial (ADNmt) para examinar la filogeografia de Picoides albolarvatus, una de las especies de carpinteros menos estudiada de Norte America. La distribucion 'mismatch' y el valor calculado de la D de Tajima, indican queen general la historia filogeografica de la especie esta caracterizada por una expansion reciente en el rango de distribucion, que probablemente ocurrio despues del inicio del Pleistoceno. Adicionalmente, un analisis filogeografico de clados anidados indica que otros procesos tales como una fragmentacion alopatrica y flujo de genes restringido, han influenciado la historia evolutiva de esta especie. Tradicionalmente, P. albolarvatus ha sido dividido en dos subespecies cuyas distribuciones convergen en la parte norte de las Montanas Transversales en California. Las dos subespecies se diferencian morfologicamente. La subespecie ubicada hacia el sur tiene un pico mas largo en proporcion al tamano del cuerpo, comparado con la subespecie ubicada mas al norte. La variacion geografica en el ADNmt es concordante con la division en las Montanas Transversales, que a su vez corresponde a la variacion morfologica observada entre las dos subespecies. Un analisis de varianza molecular indica que el 27% de la variacion geneetica es el resultado de las diferencias entre la subespecie del norte y la del sur. Incluso las aves en la parte norte del rango de distribucion se diferencian de aquellas en la parte sur del tango en al menos una sustitucion de bases. Estos resultados concuerdan con la hipotesis de que el pico mas largo de la subespecie del sur es el resultado de una adaptacion local reciente a la alimentacion basada en los conos grandes de Pinus coulteri.

The recognition of the importance of spatial scale in ecology has led many researchers to take multiscale approaches to studying habitat associations. However, few of the studies that investigate habitat associations at multiple spatial scales have considered the potential effects of cross-scale correlations in measured habitat variables. When cross-scale correlations in such studies are strong, conclusions drawn about the relative strength of habitat associations at different spatial scales may be inaccurate. Here we adapt and demonstrate an analytical technique based on variance decomposition for quantifying the influence of cross-scale correlations on multiscale habitat associations. We used the technique to quantify the variation in nest-site locations of Red-naped Sapsuckers (Sphyrapicus nuchalis) and Northern Flickers (Colaptes auratus) associated with habitat descriptors at three spatial scales. We demonstrate how the method can be used to identify components of variation that are associated only with factors at a single spatial scale as well as shared components of variation that represent cross-scale correlations. Despite the fact that no explanatory variables in our models were highly correlated (r < 0.60), we found that shared components of variation reflecting cross-scale correlations accounted for roughly half of the deviance explained by the models. These results highlight the importance of both conducting habitat analyses at multiple spatial scales and of quantifying the effects of cross-scale correlations in such analyses. Given the limits of conventional analytical techniques, we recommend alternative methods, such as the variance-decomposition technique demonstrated here, for analyzing habitat associations at multiple spatial scales. Key words: habitat selection, logistic regression, multicollinearity, nest site, scale, statistical analysis, variance decomposition. Resumen. El reconocimiento de la importancia de la escala espacial en la ecologia ha llevado a muchos investigadores a tomar enfoques de escalas multiples para estudiar las asociaciones de habitat. Sin embargo, pocos de los estudios que han investigado las asociaciones de habitat a varias escalas espaciales han considerado los efectos potenciales de las correlaciones a traves de escalas en las variables de habitat medidas. Cuando las correlaciones a traves de escalas en dichos estudios son fuertes, las conclusiones acerca de la importancia relativa de las asociaciones de habitat a distintas escalas espaciales podrian ser inexactas. En este estudio adaptamos y demostramos el uso de una tecnica analitica basada en la descomposicion de la varianza para cuantificar la influencia de las correlaciones sobre las asociaciones de habitat a traves de escalas multiples. Empleamos esta tecnica para cuantificar la variacion en la ubicacion de sitios de nidificacion de Sphyrapicus nuchalis y Colaptes auratus en asociacion con descripciones del habitat a tres escalas espaciales. Demostramos como puede utilizarse el metodo para identificar los componentes de la variacion que estan asociados solo con factores a una escala espacial, ademas de los componentes compartidos que representan correlaciones entre escalas. A pesar de que las variables de prediccion incluidas en nuestros modelos no estuvieron estrechamente correlacionadas (r < 0.60), encontramos que los componentes de variacion compartidos que reflejan correlaciones entre escalas fueron responsables de cerca de la mitad de la desviacion explicada por los modelos. Estos resultados resaltan la importancia de realizar estudios sobre el habitat a escalas espaciales muiltiples y de cuantificar los efectos de las correlaciones a traves de escalas en dichos analisis. Dadas las limitaciones de las tecnicas analiticas convencionales, recomendamos el uso de metodos alternativos (como la tecnica de descomposicion de varianza aqui demostrada) para analizar las asociaciones de habitat a escalas espaciales multiples.

We investigated patterns of seasonal variation in body weight in six populations of five resident species of temperate-zone woodpeckers: Acorn Woodpecker (Melanerpes formicivorus), Red-bellied Woodpecker (M. carolinus), Red-cockaded Woodpecker (Picoides borealis), Downy Woodpecker (P. pubescens), and Great Spotted Woodpecker (Dendrocopos major). After controlling for time of day and overall body size, annual variation in body weight was small and generally not statistically significant. However, analysis revealed evidence of significant 'winter fattening,' comparable in magnitude to other temperate-zone resident species, in three of the species. The degree of winter fattening did not correlate with either the size of the acorn crop (for the Acorn Woodpecker) of latitude, two variables potentially related to predictability of food resources. However, the smaller species exhibited significantly greater winter fattening than the larger species, as predicted by the hypothesis that energy storage should he more important for small-bodied species. Furthermore, the food-storing Acorn Woodpecker exhibited considerably less winter fattening than the nonfood-storing species, supporting the hypothesis that food storage provides an ecological alternative to winter fattening. Key words: body mass, body weight, fat storage, food storage, Piciformes, seasonality, woodpeckers. Investigamos los patrones estacionales de variacion en el peso corporal en seis poblaciones de cinco especies residentes de pajaros carpinteros de la zona templada: Melanerpes formicivorus, M. carolinus, Picoides borealis, P. pubescens y Dendrocopos major. Tras controlar por la hora del dia y el tamano corporal general, la variacion annual en el peso fue pequena y en general no significativa estadisticamente. Sin embargo, los analisis evidenciaron que tres de las especies experimentan un 'engordamiento invernal' comparable en magnitud al documentado para otras aves residentes de la zona templada. El grado de engordamiento invernal no se correlaciono con el tamano de la cosecha de bellotas (para M. formicivorus) ni con la latitud, dos variables potencialmente relacionadas con la predecibilidad de los recursos alimenticios. Sin embargo, las especies de menor tamano engordaron significativamente mas que las especies de tamano mas grande, una prediccion de la hipotesis que plantea que el almacenamiento de energia deberia ser mas importante para las especies de cuerpo pequeno. Ademas, M. formicivorus, una especie que almacena alimentos, exhibio un engordamiento de invierno considerablemente menor que las especies que no almacenan alimentos, lo que apoya la hipotesis de que el almacenamiento de alimento representa una alternativa ecologica al engordamiento.

Adult and juvenile plumage characters were traced onto a well-resolved molecular based phylogeny for Picoides woodpeckers, and a simple phylogenetic test of homology, parallelism, and convergence of plumage characters was performed. Reconstruction of ancestral character states revealed multiple events of independent evolution of derived character states in most characters studied, and a concentrated changes test revealed that some plumage characters evolved in association with habitat type. For example, there was a statistically significant association between loss of dorsal barring and use of densely vegetated habitats among Picoides species. Two analyses indicated that convergence, as opposed to parallel evolution or shared ancestry, underlies the similarity in plumage patterns between the Downy (Picoides pubescens) and Hairy (P. villosus) Woodpeckers. Possible causal explanations for convergence in plumage patterns may include mimicry and interspecific territoriality. Key words: adaptation, character evolution, convergence, Picoides, plumage, woodpeckers. Se reconstruyo la evolucion de caracteres del plumaje de individuos adultos y juveniles con base en una filogenia molecular bien resuelta de los pajaros carpinteros del genero Picoides. El estudio provee una prueba filogenetica sencilla de homologia, paralelismo y convergencia para los caracteres de plumaje. Las reconstrucciones de estados de caracter ancestrales revelaron multiples eventos de evolucion independiente de estados de caracter derivados en casi todos los caracteres estudiados, y una prueba de cambios concentrados revelo que algunos caracteres del plumaje evolucionaron en asociacion con el tipo de habitat. Por ejemplo, existe una asociacion estadisticamente significativa entre la perdida de barras dorsales y el uso de ambientes con vegetacion densa en las especies de Picoides. Dos analisis indicaron que la similitud en los patrones de plumaje entre Picoides pubescens y P. villosus puede explicarse por convergencia, no por evolucion paralela o por ancestria comun. Se discuten posibles explicaciones causales para la convergencia, como la imitacion y la territorialidad interespecifica.

Rupelramphastoides knopfi, a new genus and species of the Pici (barbets, woodpeckers, and allies), is described from Frauenweiler, a Lower Oligocene (30-34 mya) fossil site in Germany. The disarticulated skeleton of the new species constitutes the first associated remains of a fossil member of the Pici and is the smallest known species and earliest substantial fossil record of this taxon. Despite an overall resemblance to modern Ramphastidae, R. knopfi appears to be distinguished from crown group Pici by several plesiomorphic characteristics. It is classified 'family incertae sedis,' pending discovery of additional, better-preserved specimens. The fossil record and geographic occurrence of the basal lineages within the crown group are in concordance with an Old World origin of the Pici. The reasons that led to extinction of tiny Pici in Europe remain uncertain, but food competition with passeriform birds during periods of limited food availability may have played a major role. Received 27 October 2004, accepted 24 April 2005. Key words: fossil birds, Oligocene, Pici, Piciformes, Rupelramphastoides knopfi gen. et. sp. nov.

The presence of rotted wood is often noted in descriptions of woodpecker nest and roost sites, and ornithologists have found that certain fungi and species of woodpeckers, such as the red heart fungus (Phellinus pini) and Red-cockaded Woodpeckers (Picoides borealis) are intimately linked. The relationship assumed is usually one of woodpecker dependence or preference for partially decayed wood in which to excavate cavities, but the woodpecker is also sometimes suggested as a vector for the fungus. In this paper we review such associations and describe patterns evident among woodpecker nest sites that suggest microclimatic and microhabitat characteristics favoring fungal colonization of trees, woodpecker-favorable responses of trees to fungi, and ultimate use of the trees for woodpecker cavity excavation. Factors that favor fungal invasion and tree use by woodpeckers include tree species, growth history, site characteristics such as proximity to water and exposure to sun or shade, nature and position of tree injury, local climate, forest age and species composition, fire frequency, and human management activities. Woodpecker cavity height and entrance orientation may be related to the dispersal dynamics of fungi, which in turn may be related to forest vegetation, thermal, and hydric characteristics. Key words: cavity, fungi, nest-site correlates, nest-site selection.

Data on spacing behavior of the Eurasian Three-toed Woodpecker (Picoides tridactylus) are rare, and systematic observations are lacking. 1 used homing technique (>90%) and triangulation to document range use of 28 radiotagged birds in an alpine mountain forest in southeastern Germany between 1994 and 2000. Common home range of a pair ([bar]x [+ or -] SE, n = 10) identified by the adaptive kernel method (95% use distribution) during the nesting period averaged 86.4 [+ or -] 23.4 ha and varied a great deal between pairs (range 33.9-287.4 ha). Although ranges of females (69.4 [+ or -] 15.4 ha, n = 14) appeared larger than those of males (45.7 [+ or -] 10.3 ha, n = 10), the difference was not significant. Prior to nesting and during the postnesting period, both sexes used seemingly larger home ranges than during nesting ([less than or equal to] 381.7 ha); but again, the difference was not significant. Home ranges of mates (n = 20) during the nesting period overlapped an average of 66.5 [+ or -] 5.7% ([less than or equal to] 100.0%); female ranges and core areas overlapped male ranges to a significantly greater extent than male ranges overlapped those of females. Nearly all home ranges bordered or overlapped those of their neighbors. Ranges of neighboring male-female combinations (n = 11) overlapped by 17.6 [+ or -] 3.9% during the nesting period, with an increasing tendency to overlap toward the end of the breeding season. Because areas used by Eurasian Three-toed Woodpeckers remained stable over the breeding season, I propose consideration of home ranges during nesting as a reliable estimate of species area requirements for use in management plans. Received 22 August 2002, accepted 4 October 2003.

We observed a young male Red-cockaded Woodpecker (Picoides borealis) about 35 days old being fed by adults associated with a neighboring territory. A survey of biologists studying this species revealed similar acts of adoption had been observed elsewhere, but the behavior appeared to be very rare. Adoption generally implies a cost to adults because care is provided to unrelated young, but the situation is complicated in cooperative breeders such as the Red-cockaded Woodpecker. Adopted birds can help breeding adults raise additional young, and the adopted male we observed remained as a helper in its adopted territory and fed young the following breeding season. Received 4 December 2002, accepted 12 March 2003., Acts of adoption (parental care of presumably unrelated offspring) have been recorded in The Red-cockaded Woodpecker is an endangered species (Lennartz and Henry 1985) with a social breeding system (Lennartz [...]

The White-backed Woodpecker (Dendrocopos leucotos) is one of the rarest European woodpeckers and its populations have declined markedly during the last century in many European countries. The objective of our study was to investigate the selection of nesting and feeding trees by the subspecies D. l. lilfordi, a field not previously investigated. We conducted this study in a mountain area of central Italy characterized by wide and homogeneous tracts of beech- (Fagus sylvatica) forested slopes. The rate at which we detected the species was highly correlated with the mean trunk dbh of the stand; the more mature the stand, the greater the number of woodpecker detections. The White-backed Woodpecker was dependent upon trees that were mature, dead, or in an advanced degree of decay for both nesting and foraging. The habitat specialization of the species suggests that forest stand management should promote longer harvesting rotations, preserve dead and decaying trees, create new foraging sites, and prevent excessive fragmentation of forested landscapes. Received 14 February 2003, accepted 9 Jane 2003., Habitat requirements regarding nesting and feeding sites are important components of habitat selection by birds and are fundamental aspects in the conservation of endangered species, particularly those species that specialize [...]

Individuals in a number of bird species have the opportunity to maintain contact with their mates during nonbreeding periods. This contact may be important to synchronize the partners' reproductive cycles before breeding begins. As a first step toward exploring the function of pair bond maintenance in non-breeding birds, I studied the behavior of three pairs of Pileated Woodpeckers (Dryocopus pileatus) and an unpaired male at roost sites during autumn. At dawn and dusk, paired individuals exchanged visual, vocal, and other acoustical signals identical to those given during the breeding season. Demonstration tapping away from a nest is reported here for the first time. The possible function of these behaviors may be related to monitoring the partner's condition and investing in the pair bond to enhance future reproductive success. Received 19 September 2002, accepted 01 March 2003., The pair bond of many birds is formed each spring as courting birds establish a relationship with their future mate. Once the nesting season ends, many birds cease to maintain [...]

We studied snag use for foraging by Black-backed Woodpeckers (Picoides arcticus) one year after a tire in an eastern black spruce (Picea mariana) boreal forest in Quebec, Canada. We searched for signs of foraging (bark flaking and excavation holes) by Black-backed Woodpeckers on 6,536 snags sampled in 56 plots located in portions of the burned forest that had not been salvage logged. A logistic regression model was developed based on the presence or absence of foraging signs. Results showed that Black-backed Woodpeckers used larger snags that were less deteriorated by tire (qualified as high-quality snags). Direct field observations of individuals foraging on 119 snags also indicated that used snags corresponded to those of high predicted quality. Finally, we assessed the relationship between food availability and snag characteristics by measuring the density of wood-boring beetle larvae holes on 30 snags of different size and deterioration classes. High-quality snags contained higher prey densities (wood-boring beetle holes) than smaller and more deteriorated snags. We recommend that forest blocks characterized by large and less deteriorated trees be preserved from salvage logging in recently burned boreal forests in northeastern North America. Received 6 December 2001, accepted 14 December 2002.

We compared species composition, insect parasitism, and mass of acorns stored in 12 granaries with acorns present within the territories of Acorn Woodpeckers (Melanerpes formicivorus) at Hastings Reservation in central coastal California. All three species of oaks present in the study area produced excellent crops the year of the study, and thus woodpeckers could readily have filled their granaries with acorns of any one of the species. Nonetheless, species composition of stored acorns was highly variable among territories and at least some acorns of all three species were stored in all granaries. There was no consistent difference in insect parasitism between stored and unstored acorns. Relative to estimated availability, birds preferred to store Quercus lobata acorns and avoided Q. douglasii acorns, but showed no preference for Q. agrifolia acorns even though they are energetically more valuable than the other two species. Stored acorns of two of the three oak species also weighed less, and were thus presumably smaller, than the average unstored acorn. On average, Acorn Woodpeckers did not maximize the energetic value of their stores and could have increased the energy stored in their granaries by 14-108% had they chosen larger acorns or more energetically rich Q. agrifolia acorns. Storing may be better understood in a more traditional optimal foraging context in which the costs of harvesting and caching, together with the energetic value of stored acorns, are considered together. Key words: caching, food storage, granary, insect damage, Melanerpes formicivorus, oaks.

Study sampled number of arthropods on longleaf and loblolly pines to determine which type of tree harbored the most arthropods, which are an important food source for the endangered red-cockaded woodpecker. Longleaf pine harbored significantly larger numbers of arthropods, which indicates that retaining or restoring this tree species in red-cockaded woodpecker habitats should increase the food supply for these birds.

Few studies have examined survivorship of animals in forest fragments differing in size, and none has used appropriate mark--recapture analysis techniques taking into account probability of recapture. Using Program MARK, a flexible mark--recapture software package, we estimated annual survival rates of four permanent-resident woodland bird species over a 5-yr period in a fragmented landscape. For Carolina Chickadees, White-breasted Nuthatches, and Downy Woodpeckers, the probability of survival was related to site, with survival being highest in large woodlots, low in small woodlots, and either intermediate or lower in riparian woodlands. The presence of supplemental food had a positive influence on survivorship. Survivorship of the Tufted Titmouse was lower in years with heavy snow cover. There was some evidence for an age difference in apparent survival, with adult birds having higher survival rates. Overall, however, these age-specific estimates had large variances or the differences disappeared when models were averaged, except in the chickadee, where young birds appeared to survive less well in forested river corridors. This last result was quite likely due, at least in part, to age-specific dispersal, suggesting that river corridors function as important dispersal routes for young, transient birds of permanent-resident species. These results suggest a strong additional cost of fragmentation: increased mortality. This cost has not been previously documented using modern mark--recapture analytical techniques. Key words: annual survival; Baeolophus bicolor; Carolina Chickadee; corridor dispersal; Downy Woodpecker; forest fragmentation; mark-recapture; Picoides pubescens; Poecile carolinensis; Sitta carolinensis; Tufted Titmouse; White-breasted Nuthatch.

Lewis's Woodpecker (Melanerpes lewis) has been characterized as a 'burn specialist' because of its preference for nesting within burned pine forests. No prior study, however, has demonstrated the relative importance of crown-burned forests to this woodpecker species by examining its reproductive success in different forest types. We studied breeding Lewis's Woodpeckers in cottonwood (Populus fremontii) riparian forest patches of Colorado and crown-burned ponderosa pine (Pinus ponderosa) forests of Idaho to compare their reproductive success, productivity, and potential source-sink status in the two forest types. Daily nest survival rates were significantly lower in cottonwood compared to burned pine forests. Nesting success was 46% (n = 65) in cottonwood forests and 78% (n = 283) in burned pine forests. Proportion of nests destroyed by predators was significantly higher in cottonwood forests (34%) compared to burned pine forests (16%). We consistently found crown-burned forests to be potential source habitat, whereas cottonwood riparian sites were more often concluded to be potential sink habitat. Cottonwood riparian forests were surrounded primarily by an agricultural landscape where the composition and abundance of nest predators was likely very different than the predator assemblage occupying a large-scale burn in a relatively natural landscape. Conversion of riparian and adjacent grassland landscapes to agriculture and prevention of wildfire in ponderosa pine forests have likely reduced nesting habitat for this species. Prescribed understory fire is the prevailing management tool for restoring ponderosa pine ecosystems. Conditions created by crown fire may be equally important in maintaining ponderosa pine systems and conserving nesting habitat for the Lewis's Woodpecker. Key words: crown-burned forests, Lewis's woodpecker, Melanerpes lewis, nest success, Pinus ponderosa, Populus fremontii, source-sink habitats.

In order to reverse the decline in numbers of the endangered red-cockaded woodpecker in the southeastern United States, greater knowledge is required of it's habitat requirements. Research developing of a model of habitat quality for the species in the North Carolina Sandhills is presented.

Red-cockaded woodpeckers are an endangered species and can be affected by demographic isolation. One way of tackling this problem is to introduce pairs of subadult woodpeckers into habitats that are not occupied by the species. A project to release woodpeckers in eastern Texas shows that this technique is effective in reestablishing breeding units. The formation of new woodpecker pairs can be increased by reintroducing pairs in such a way that the density allows for social contact between clusters that already exist and between the adjacent pairs.

The endangered red-cockaded woodpecker is found only in the southern pine forests of the southeastern US, where it nests and roosts. Cavities have traditionally been monitored using a small drop light and mirror but the technique is very labour-intensive. A new study investigates the use of the TreeTop Peeper II system, a pole-mounted video system made by Christensen Designs. It is shown that the new system successfully and efficiently monitors red-cockaded woodpecker cavities.

Sap consumption by White-fronted Woodpeckers in woodlands has been studied and interactions with other bird species using the resource, and seasonal variations in sap exploitation were considered. Smaller bird species spent less time feeding on sap due to aggression by White fronted Woodpeckers, suggesting that the Woodpeckers actively compete for the resource. However the other bird species can take advantage of the resource that would otherwise be unavailable.

The endangered red-cockaded woodpecker is found in the pine forests of the southeastern US, where it roosts and nests in living pine trees. Its habit of cavity nesting makes it difficult to remove young for banding. A new study investigates the use of a four-pronged pick-up tool for removing red-cockaded woodpecker nestlings from cavities. The pick-up tool is shown to have several advantages over the more usual noose technique for extracting nestlings, giving decreased capture times and successfully snaring birds which could not be snared by the noose. It is recommended that the pick-up tool only be used on older-aged nestlings.

R.J. O'Connor's proposed model for the evolution of brood reduction, wherein a nestling's fitness is derived from its direct fitness component and its indirect fitness component derived from its surviving siblings, is evaluated. Mortality differentials for Red-cockaded Woodpeckers were examined to predict brood reduction and its mechanisms. Results indicated that the model is insufficient in detecting brood reduction in the years wherein it is favored by selection. Selection for brood reduction is suggested to frequently occur in broods of Red-cockaded Woodpeckers.

A wide variation in the density of red-cockaded woodpecker neighborhoods within and between populations was found in a comparison of five large populations of the birds using the ecological neighborhood concept. Ecological neighborhoods were characterized by the number of neighbors within the area of a circle with a radius of a typical dispersal distance and the distance from an active cluster to its tenth nearest neighbor. Factors contributing to this variation include the quality and number of cavities within a cluster and the quality of the foraging habitat.

The range of the Bachman's sparrow has become increasingly restricted and it is considered endangered. The species favors mature pine woodlands with dense undergrowth and habitat loss may be contributing to the sparrow's decline. Wildlife management practices in the past have focused on the similar requirements of red-cockaded woodpeckers. A new study in northwestern Florida determines whether management practices aimed at conserving the red-cockaded woodpecker benefit Bachman's sparrows. The study shows that areas suitable for woodpeckers are sometimes unsuitable for Bachman's sparrows and suggests that burning is important to maintain the dense undergrowth they prefer.

Woodpeckers were censused in 60 fixed-radius (300 m) circular plots (divided into eight 45°-arc pie-shaped sectors) in mature forests (60-80 years-old) of three forest types (20 plots per type) in eastern Texas: bottomland hardwood forest, longleaf pine (Pinus palustris) savannah, and mixed pine-hardwood forest. A total of 2242 individual woodpeckers of eight species was detected in 144 h of censusing. Vegetation characteristics in plot sectors with and without woodpeckers were compared. Woodpecker presence and abundance were primarily associated with the occurrence of large snags and logs. Red-bellied Woodpeckers (Melanerpes carolinus) were the most abundant and widespread species, especially in areas containing more hardwoods than pines. Red-cockaded Woodpeckers (Picoides borealis) were the least abundant and most habitat-restricted woodpecker, occurring only in the longleaf pine savannah. Pileated Woodpeckers (Dryocopus pileatus) were the most evenly distributed species among the forest types, but occurred primarily in mature forests with large snags and logs. Bottomland hardwood forests were important for Northern Flickers (Colaptes auratus), Redheaded Woodpeckers (Melanerpes erythrocephalus), and Yellow-bellied Sapsuckers (Sphyrapicus varius) during the fall and winter, and for Downy Woodpeckers (Picoides pubescens) during the summer and winter. The Hairy Woodpecker (P. villosus) was most frequently encountered in areas of recent disturbance in the mixed pine-hardwood forests, especially in fall. Vocal imitation of a Barred Owl (Strix varia) increased the number of woodpecker detections by 71%. Received 14 Jan. 1997, accepted 10 May 1997., Woodpeckers are generally considered to be valuable species because they eat a variety of insects considered to be harmful to forests (Steirly 1965, Dickson et al. 1979). As primary cavity [...]

Lewis' Woodpeckers (Melanerpes lewis) on the plains in the Arkansas River valley and in the foothills of the Wet Mountains in southeastern Colorado used large, dead or decaying broadleaf cottonwoods (Populus deltoides) for breeding and for winter mast storage. On the plains, they nested near fallow and mowed fields, but avoided anthropogenic structures and grazed fields. During the 1992-1993 winter, woodpeckers occupied sites near corn fields, and stayed on these sites into the 1993 breeding season. In the foothills, they avoided dense stands of trees at all times of year, nested near grazed fields, and wintered near oaks. Riparian habitats were particularly important to Lewis' Woodpeckers in southeastern Colorado, especially those with large mature cottonwoods., Lewis' Woodpeckers (Melanerpes lewis) were placed on the Audubon Society's Blue List for 1975 (Arbib 1974), and local population declines have been recorded in Utah and in British Columbia (Behle [...]

Recent research undertaken in a population of red-cockaded woodpeckers in the Apalachicola National Forest in Florida indicates no connection between the number of young fledged and the availability of pine trees or extent of habitat fragmentation. No evidence was produced to refute the theory that reproductive success and group size are the same for groups with varying amounts of available foraging habitat. In terms of the management of foraging, the research indicates that no moves should be taken against actions designed to benefit red-cockaded woodpeckers long-term.

ABSTRACT.--We examined woodpecker excavation and use of artificial polystyrene snags in four forest types in eastern Texas for five years. Twenty-three of 47 artificial snags were used by Downy Woodpeckers [...]

Existing theory and empirical evidence suggest that body size should have a profound influence upon the composition of flight muscles and the performance of intermittent flight in birds. I examine the relationships between functional morphology and intermittent flight behavior within a closely-related group of birds using six species of woodpeckers (Picidae): Downy Woodpecker (Picoides pubescens, 27.2 g), Red-naped Sapsucker (Sphyrapicus nuchalis, 47.4 g), Hairy Woodpecker (P. villosus, 70.5 g), Lewis' Woodpecker (Melanerpes lewis, 106.6 g), Northern Flicker (Colaptes auratus, 148.1 g), and Pileated Woodpecker (Dryocopus pileatus, 262.5 g). In woodpeckers with a body mass less than 100 g, the pectoralis muscle was composed mostly of red (R) fibers, with intermediate (I) fibers either absent or restricted to lateral regions. R and I fibers were found in all regions of the pectoralis in the larger species. Positive scaling of the percent and cross-sectional diameter of I fibers may explain why species larger than 100 g flap-bounded when theory predicts they should not have sufficient power. Differences were evident in staining characteristics of I fibers among (but not within) species. Phylogenetic effects were apparent because hypothesized sister taxa shared similarities in muscle composition. Internal and external wing dimensions scaled according to the predictions of geometric similarity, but the Red-naped Sapsucker and Lewis' Woodpecker possessed slightly higher wing-shape indices (narrower, more-pointed wings) than the other species, which may reflect migratory and flycatching behavior as well as phylogeny. All of the species exhibited flap-bounding. The number of flaps in a flapping phase, wingbeat frequency, flapping-phase duration, and bounding-phase duration all scaled negatively with body mass, whereas the percent time spent flapping and flight speed scaled slightly positively. Lewis' Woodpecker was unusual in its intermittent flight behavior by spending more time flapping, using lower wingbeat frequencies and flying slower than would be expected for its body mass. It was the only species to pursue flying insects using highly maneuvered flights including extended glides, although the Red-naped Sapsucker was observed to flycatch without gliding. Slow flight speed, rather than wing design, was related to gliding in the Lewis' Woodpecker. I fibers in the pectoralis of the Lewis' Woodpecker were unique in showing intense glycolytic potential, perhaps reflecting the species' foraging style.

A study has been conducted to measure the population size of the red-cockaded woodpecker, Picoides borealis, on the Piedmont National Wildlife Refuge and Hitchiti Experimental Forest in Georgia by using population viability analysis. The population size of newly banded and unbanded birds were analyzed based on two demographic parameters: population dynamics and extinction. Results of the study suggest that red-cockaded populations in PNWR-HEF face no danger of extinction.

Difficulties in developing management techniques for the preservation of endangered species led zoologists to create a male-only, stage-based matrix model for evaluating management techniques for red-cockaded woodpeckers. The study predicted the effect of the techniques to the population dynamics of the woodpeckers. Results showed that the protection of the nesting areas are most likely to enhance the populations.

The geographic variation in coloration and morphology of Acorn Woodpeckers was investigated. One thousand five hundred and thirty-one study skins of Acorn Woodpeckers from 16 museum collections were studied with respect to locality, elevation above sea level, date of collection, iris color, sex and age. All measurements were made using the same set of calipers to ensure accuracy. Highly significant geographic differences in coloration and morphology were observed between the species.

Red-cockaded Woodpeckers (Picoides borealis) near the southern extreme of the species' range had a low fledgling rate, high fledgling survivorship, and high level of breeder experience and adult survivorship compared to other populations. Breeding male and female survivorship was 10% and 23% higher, respectively, than northern populations. Tenure of helpers was higher than other populations, apparently as a result of high adult survivorship. The frequency of female helpers was higher (30%) than reported for other populations (5%). Group size ranged from two to five members and averaged 2.4 birds prior to nesting. Reproduction in central Florida was lower than other populations (1.0 vs 1.6 fledglings per group). Experienced pairs without a helper produced significantly more fledglings than experienced pairs with a helper (1.45 and 0.87 fledglings/group, respectively). Reproductive success was correlated with breeder experience, outside intrusion rate, and territory size.

We characterized composition, density, and structure of habitat occupied by red-cockaded woodpeckers (Picoides borealis) on the Daniel Boone National Forest (NF), Kentucky, and we compared areas surrounding active and abandoned cavity trees. Basal area of active colonies (22.7 [msup.2]/ha) was composed of 48% pine (chiefly Pinus echinata) and 52% nonpine (chiefly Quercus spp.); density (2,257 stems/ha) and hardwood abundance (88% of total stems) were much higher than recorded in red-cockaded habitat elsewhere. Stand characteristics did not differ between areas immediately surrounding active and abandoned trees, but areas surrounding abandoned colonies had lower percentage (P [unkeyable] 0.04) of habitat dominated by pine and pine-oak and greater percentages (P [unkeyable] 0.02) of stands that had been harvested. Damage to cavity trees by pileated woodspeckers (Dryocopus pileatus) was greater (P < 0.002) on abandoned areas. The availability of suitable habitat was apparently the major limitation to red-cockaded woodpecker populations; hence management should emphasize the maintenance of, or increase in, the area occupied by mature and stands of pine and pine-oak.

ABSTRACT.--We document for the first time a Red-naped Sapsucker (Sphyrapicus nuchalis) usurping the nest of a Red-breasted Nuthatch (Sirra canadensis). A nuthatch nest in the incubation phase was usurped by [...]

I report observations of fruit consumption by Magellanic Woodpeckers (Campephilus magellanicus) and an opportunistic predation on a lizard (Liolaemus sp.) by an adult male. During normal feeding activities, the woodpecker snatched from a bark crevice of a lenga (Nothofagus pumilio) tree a lizard, which he then beat until stunned or dead, before flying off carrying the reptile. Frugivory, although undocumented for this species, is widespread among picids. Conversely, this apparently first observation of a Magellanic Woodpecker preying on another vertebrate adds to a few known cases of vertebrate predation by woodpeckers. Received 6 August 2002, accepted 22 February 2003., Weighing 276-363 g, the Magellanic Woodpecker (Campephilus magellanicus) is the largest Neotropical picid (Short 1982). It is restricted to the Austral Temperate Forests of Chile and Argentina (35-56° S), where [...]

The Red-cockaded Woodpecker (Picoides borealis) is a federally endangered cavity nesting species. Mesh snake traps are placed near the base of cavity trees to prevent tree climbing and potential nest predation by rat snakes. In 1997, we documented one live and four dead Red-cockaded Woodpeckers ensnared in mesh snake traps at the Bienville National Forest and Noxubee National Wildlife Refuge, Mississippi., The Red-cockaded Woodpecker (Picoides borealis) is a federally endangered species that inhabits mature, open pine forests throughout the southeastern United States (Jackson 1994). Red-cockaded Woodpeckers excavate cavities in live pines [...]