Parental care in animals can be costly and is shared between both parents in many bird species. Not surprisingly, most studies of how parental care is shared between the sexes are in sexually dimorphic species, and much less in known about sexually monomorphic species where sex cannot be determined in the field. This has prevented a full understanding of parental care behaviors – which are intrinsically linked to fitness – in species such as the Red-headed Woodpecker (Melanerpes erythrocephalus) that is experiencing population declines throughout much of its range. In this study we assessed whether Redheaded Woodpecker brooding time, nestling provisioning rates, and nest cleaning rates vary as a function of parent sex, habitat type (savanna and closed canopy forest), brood size, nestling age, temperature and/or date. We recorded and analyzed 128 hours of high-quality video from 21 broods at Fort A.P. Hill, Virginia where this species is relatively abundant. We captured and color-banded Red-headed Woodpeckers, taking breast feather samples for genetic sexing, and determined brood size and chick age of nests using an extendable pole camera. Using generalized linear mixed models, we found the best predictor of nestling provisioning was an interaction between chick age and date; older chicks were fed more frequently in early summer (before 7 July) compared to late summer. The seasonal reduction in provisioning could be related to a reduction in resource availability, but whether or not provisioning in later nests affects nestling survival warrants further study. We found chick age and parent sex to be the best predictors in brooding models, with females brooding more when chicks are less than 10 days old and males being the only parent to enter the cavity after 10 days. Additionally, males almost exclusively remove fecal sacs from nests, highlighting an observational method to determine sex of breeding adults in the field. Such division of reproductive roles is similar to what is known for dimorphic woodpecker species and likely indicates energetic constraints due to the need for high parental investment from both sexes. Parental care is inextricably linked with habitat quality and home range size. Parents will travel to obtain the resources necessary to provision their young, and larger home ranges during the demanding nestling provisioning stage may indicate increased effort resulting from fewer available resources near the nest. We estimated home range sizes of 25 breeding adult Red-headed Woodpeckers using PinPoint GPS tags and 95% kernel density estimates (KDEs) with plug-in smoothing factors. We modeled the effects of habitat, sex, nest stage, date, and distance to nearest neighbor on home range estimates. Red-headed Woodpecker males have larger home ranges than females, and late summer home ranges are smaller than those measured before 7 July. More study is needed to determine if sex or date is a stronger factor on home range, given our naive sampling which resulted in more females sampled in late summer and observations that did not continue to the end of the breeding season (late August). Since we found date to be an influential factor to both provisioning rate and home range size, it is possible that seasonal resource changes are an important, unstudied factor related to nationwide declines of this species.

Thesis (M.S.)--North Carolina State University, 2003. / Title from PDF t.p. (viewed on May 16, 2004). Includes vita. Includes bibliographical references (p. 58-63).

No description available.

Geninių paukščių apskaitos buvo vykdomos 2007 – 2008 metais, kovo – gegužės mėnesiais. Siekiant, kad surinkti duomenys kuo tiksliau atspindėtų geninių paukščių populiacijų rūšinę ir kiekybinę sudėtį, maršrutai buvo planuojami skirtingose ekologiniu ir antropogeniniu poveikiu aplinkose. Tyrimams buvo pasirinktos 4 skirtingos vietos: Raseinių miškų urėdijos Paliepių girininkijai priklausantis Paliepių miškas, Vilniaus miškų urėdijai Lavoriškių girininkijai priklausantis Lavoriškių miškas, Ignalinos miškų urėdijai Kaltanėnų girininkijai priklausantis Pakretuonės miškas ir Vilniaus miesto Vingio parkas. Apskaitų metu iš viso buvo pastebėtos 7 geninių paukščių rūšys: didysis genys, vidutinis genys, mažasis genys, baltnugaris genys, tripirštis genys, juodoji meleta ir žalioji meleta. Didžiausias rūšių skaičius buvo užregistruotas Vingio parke. Dažniausiai sutinkami buvo didysis genys ir juodoji meleta. Didžiausiu vietinių populiacijų tankumu pasižymi didysis genys. Palyginus 2007 – 2008 metų duomenis, Geninių paukščių populiacijų gausa visose tirtose vietovėse didėjo, tačiau pokyčiai nėra statistiškai patikimi. Nustatyta, kad dažniausios geninių paukščių rūšies – didžiojo genio vietinių populiacijų tankumui didžiausią įtaką turi: pirmojo medžio ardo amžius, medyno medžių rūšių įvairovė ir negyvos medienos kiekis medynuose. / Registration of woodpecker was carried out from March to May in 2007-2008. For the purpose of getting the data which would be as accurate as possible from the aspect of the woodpecker population species and quantity, the routes were planned in the environments differing in ecological and anthropological effect. 4 different sites were chosen for the research: Paliepiai forest that belongs to Paliepiai forestry of Raseiniai forester’s district, Lavoriskes forest that belongs to Lavoriskes forestry of Vilnius forester’s district, Pakretuone forest that belongs to Kaltanenai forestry of Ignalina forester’s district and Vilnius city Vingis Park. During registration 7 species of woodpeckers were observed: great spotted woodpecker, middle spotted woodpecker, lesser spotted woodpecker, white – backed woodpecker, three – toed woodpecker, black woodpecker and green woodpecker. The largest number of species was registered in Vingis Park. The species that are found most often are the great spotted woodpecker and the black woodpecker. The great spotted woodpecker is known for the greatest density of local populations. By comparing the data of 2007-2008 the abundance of populations of woodpeckers increased in all the surveyed sites, however, the changes are not statistically reliable. It has been found out that the density of the most frequent species of woodpeckers, i.e. the great spotted woodpecker, is most influenced by the following factors: the age of the first layer of the tree... [to full text]

Den vitryggiga hackspetten har sedan 1970 varit en starkt hotad art i Sverige tack vare förändrade habitat till följd av ett industrialiserat skogsbruk med stor fokus på barrträd vilket inte är ett optimalträd för den vitryggiga hackspetten. Idag finns det cirka 3 häckande par kvar i Sverige. I Finland och Lettland uppvisar den vitryggiga hackspetten en stark närvaro med en stor population då skogsbruket i dessa länder skiljer sig markant mot Sverige i form av typ av träd och hantering av död ved. Syftet med studien som utförts i den här rapporten är att bedöma om ett område vid sjön Erkens norra strand kallat Hasselhorn i Stockholms län uppnår de riktlinjer Naturvårdsverket har satt på minst 20m3/ha död lövved i trakten samt en medelålder på >80 år för att ett område ska anses vara ett optimalområde för den vitryggiga hackspetten. Fokustrakten identifierades med IR-bilder för att avgöra om området var rikt på lövträd och ett område på 110ha ritades in. Sextio stickprov slumpades ut i området där levande och döda träd mättes in med klave och höjdmätare för att beräkna m3/ha och ålder bedömdes visuellt för varje mätområde. Studien påvisar att Hasselhorn idag inte uppnår optimal status för alla parametrar som satts upp av Naturvårdsverket för att det ska utgöra ett lämpligt habitat för den vitryggiga hackspetten. Däremot uppnår området kravet på mer än 20m3/ha och mer än 75 % lövträd satta av Naturvårdsverket. Området uppnår dock inte medelåldern >80 år. Även artfördelningen i regionen av levande träd visar på mycket lite barrträd och stor tillgång på asp som anses vara det främsta trädet för födosök för den vitryggiga hackspetten som visar på att Hasselhorn kan uppnå god status inom ett fåtal år om särskilda naturvårdsåtgärder sker i området. / The white-backed woodpecker has been a highly threatened in Sweden since 1970 due to drastically changed habitats as a result from industrialized forestry methods with a high focus on conifers. Today there are only 2 known breeding pairs left at Dalälven in Sweden. Compared to Finland and Latvia the white-backed woodpecker exhibits a strong presence with large populations as the forestry industry in these countries differs from Sweden in terms of what type of trees they use and how they manage dead wood. The purpose of this study is to assess whether an area at lake Erken’s northern shore called Hasselhorn in Stockholm County achieves the guidelines determined by Naturvårdsverket. Naturvårdsverket has determined that the white-backed woodpecker at least need 20m3/ha dead deciduous trees in a habitat and an average age of >80 years to be considered as an optimal area for the white-backed woodpecker. The focus area was localized with IR-images to determine an area rich with deciduous trees and an area of 100ha was drafted. Sixty sample points were randomized in the area. All living and dead trees at each points were measured with a tree caliper and clinometer to determine the amount of wood in m3/ha. Age was determined visually for each sample point. The study showed that Hasselhorn currently does no achieve the optimal status for all parameters in the study to make it a suitable habitat for the white-backed woodpecker. On the other hand, the area does meet the guideline set by Naturvårdsverket of more than 20m3/ha dead deciduous wood and more than 75% deciduous trees in the area, however it does not show an average age of >80 years. Species distribution of living deciduous trees exhibits large volumes of aspen, which is considered to be a main source of food since they contain the type of bugs preferred by the white-backed woodpecker. With the right conservation methods, the study shows that Hasselhorn can become a viable habitat for the white-backed woodpecker in the near future.

Geographic information systems (GIS) technology was used to analyze factors influencing habitat use by an endangered species, the red-cockaded woodpecker. The study area was the western part of the Raven Ranger District of the Sam Houston National Forest, Texas. The factors considered included both structural characteristics and spatial relationships among stands of trees in the habitat.

The main objective of this study was to find factors that influence the occurrence of three-toed woodpecker (Picoides tridactylus) in Šumava at a time when the bark beetle gradation caused by Kyrill subside. The research was conducted on five transects. To prove the presence of three-toed woodpecker was opted the method of an acoustic provocation, which reliability was well proven. The hypothesis was that the three-toed woodpecker prefers the trees infested by bark beetle instead of healthy trees. Surprisingly, however, he also prefered the stands where the main attack took place several years ago. Regardless of their health status the tree- toed woodpecker preferred non-intervention stands instead of the on- going management forest. Among other factors, the exposure was applied (preferred south and west) and elevation (median, minimum altitude of about 1100 m.). Another important result is that Picoides tridactylus prefers for its food stands still alive or just dead spruce trees infested by the bark beetle. Overall, it appears that the three-toed species has narrowly defined biotope demands, which are linked to the natural spruce forest unaffected by people. The results of this study could be used to better understanding of the ecology three-toed woodpecker, eventually can help to create a...

The red-headed woodpecker is a primary cavity excavator found throughout the Eastern Deciduous Forest and parts of the Great Plains. Although widespread, the red-headed woodpecker is generally considered uncommon, with patchily distributed populations. Over the past 50 years, this species has experienced precipitous, range-wide declines. The red-headed woodpecker uses a variety of cover types to meet resource needs across the annual cycle, ranging from oak savannas and wetlands, to mature beech forests and urban parks. Given their apparent adaptability to such a wide range of habitats, causes of declines are perplexing. To understand and stem declines, recent studies have focused on quantifying this species’ habitat requirements. Most of these studies have focused on a single cover type, often open forests, during the breeding season. However, effective management requires comprehensive knowledge of red-headed woodpecker habitat needs in a variety of cover types across the annual cycle. My thesis seeks to address this knowledge gap. I studied red-headed woodpecker habitat selection during both the breeding and non-breeding seasons at Fort A.P. Hill (FAPH) in Caroline County, Virginia. FAPH contains a variety of cover types that red-headed woodpeckers are known to use for breeding and overwintering, including: wetlands, open forests and closed forests. In Chapter 1, I investigated winter roost-site selection of red-headed woodpeckers in a burned forest stand. My study was the first to quantify winter habitat selection for this species. My aim was to identify variables driving winter roost-site selection at two relevant spatial scales, and estimate their parameter weights using logistic regression. I found that red-headed woodpeckers preferred habitat around the roost tree that contained a higher basal area of snags and mast-producing trees. They differentially selected roost trees based on taxon and decay state. My results indicate that managers should adopt practices that promote snag generation and retention, and mature oak recruitment. In chapter 2, I focused on red-headed woodpecker breeding season habitat requirements, as many other studies have done. However, unlike other studies that investigated habitat selection within a single cover type, I found and characterized nest-sites in three distinct cover types (wetlands, closed forests, open forests). I used a comparative approach to identify cover-type specific nest-habitat thresholds at the landscape, patch and tree scales using boosted regression trees (BRT). Although models at the landscape scale inadequately discriminated between nest and available sites, models at the patch and tree scales achieved excellent discrimination ability. I found that red-headed woodpeckers are consistent in their preference for a number of habitat features at the patch (high medium/large snag density, open canopy) and tree (large diameter tree with less bark) scales, irrespective of cover type context. However, I also found cover-type specific habitat preferences at the patch scale, indicating red-headed woodpeckers are flexible in their selection of features surrounding the nest and responsive to the broader habitat context. My findings suggest that there are a number of habitat features that facilitate breeding for red-headed woodpeckers generally, and management that promotes these features will be effective in a variety of habitat contexts. They also indicate that management can be tailored to provide the most suitable habitat for each of these three commonly used cover types. Together, Chapters 1 and Chapter 2 expand our knowledge of this declining keystone species’ habitat needs across the full annual cycle. But there is still much to know. The choices of habitat selection have consequences. Determining the conditions under which habitat features function to either help or harm populations is a necessary next step. While not a part of this thesis, I am currently investigating the factors that drive nest success among cover types, linking breeding-site selection to population dynamics. I also have behavioral data that will help reveal the mechanisms that either facilitate or constrain the exploitation of food resources across cover types. Finally, the red-headed woodpecker is a facultative migrant that often shifts habitat associations to take advantage of seasonally available resources. Data from my point count surveys—conducted over two successive winter and summer seasons—allow for development of dynamic occupancy models. Modeling shifts in occupancy across seasons will show the habitat factors underlying seasonal shifts. Site-specific differences in colonization, extinction and frequency of occupancy, within seasons but across years, will further our understanding of what constitutes habitat quality for this species, in both the breeding and non-breeding seasons.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 76-86).

Hydro One, a major distribution of electricity in Ontario, has reported that approximately 16,000 of the wood utility poles in its network of two million poles have been damaged by woodpeckers. With a cost of replacement of approximately $4000 per pole, replacing all affected poles is an expensive enterprise. Previous research conducted at UW attempted to quantify how different levels of woodpecker damage affected the pole strength. In the course of this research, some shear failures were observed. Utility poles being slender cantilevered structures, failures in shear are not expected. The objectives of this study were to determine the effective shear strength of wood utility poles and to determine the reliability of wood utility poles under different configurations, including poles that had been damaged by woodpeckers. An experimental programme was developed and conducted to determine the effective shear strength of wood poles. Red Pine wood pole stubs were used for this purpose. The stubs were slotted with two transverse half-depth cuts parallel to one another but with openings in opposite directions. A shear plane was formed between these two slots. The specimens were loaded longitudinally and the failure load was recorded and divided by the failure plane area to determine the shear strength. The moisture content of each specimen was recorded and used to normalize each data point to 12 % moisture content. The experimental study showed that the mean shear strength of the Red Pine specimens adjusted to 12 % moisture content was 2014 kPa (COV 47.5 %) when calculated using gross shear area, and 2113 kPa (COV 40.5 %) when calculated using net area. The shear strength of full-size pole specimens can be represented using a log-normal distribution with a scale parameter of λ = 0.5909 and a shape parameter of ζ = 0.5265. iii The reliability of Red Pine wood utility poles was determined analytically. A structural analysis model was developed using Visual Basic for Applications in Excel and used in conjunction with Monte Carlo simulation. Statistical distribution parameters for wind loads and ice accretion for the Thunder Bay, Ontario region were obtained from literature. Similarly, statistical data were obtained for the modulus of rupture and shear strength from previous research conducted at UW as well as the experimental programme conducted in this research. The effects of various properties on reliability were tested parametrically. Tested parameters included the height of poles above ground, construction grade, end- of-life criterion, and various levels of woodpecker damage. To evaluate the results of the analysis, the calculated reliability levels were compared to the annual reliability level of 98 % suggested in CAN/CSA-C22.3 No. 60826. Results of this reliability study showed that taller poles tend to have lower reliability than shorter ones, likely due to second-order effects having a greater influence on taller poles. The Construction Grade, a factor which dictates the load factors used during design, has a significant impact on the reliability of wood utility pole, with poles designed using Construction Grade 3 having a reliability level below the 98 % threshold. Poles designed based on Construction Grade 2 and 3 having reached the end-of-life criterion (60 % remaining strength) had reliability below this threshold whilst CG1-designed pole reliability remained above it. Wood poles with exploratory- and feeding-level woodpecker damage were found to have an acceptable level of reliability. Those with nesting-level damage had reliability below the suggested limits. Poles with feeding and nesting damage showed an increase in shear failure. The number of observed shear failure depended on the orientation of the damage. Woodpecker damage with the opening oriented with the neutral axis (i.e., the opening perpendicular to the direction of loading) produced a greater number of shear failure compared to woodpecker damage oriented with the extreme bending fibres.