The Corsican Nuthatch: Endangered species

Lien vers l'Inventaire National du Patrimoine Naturel INPN

De nouvelles données récemment publiées ont permis de revoir l’évaluation Liste rouge nationale de la Sittelle corse (Sitta whiteheadi). En effet, un article publié en 2011 dans Bird Conservation International par Thibault et al. indique que la population de cette espèce, endémique de Corse, est inférieure à 10 000 individus et qu’un déclin continu de sa population est observé. Les causes de ce déclin sont les feux et l’exploitation forestière des pins de Corse. Suite à la connaissance de ces nouveaux éléments, et à la sollicitation de l’avis des experts membres du comité de validation pour la Liste rouge des oiseaux de métropole, l’espèce est désormais classée dans la catégorie « vulnérable » sur les critères C1+2a(ii).

Unidentified nuthatch in Siberian Altay in July 2006

Unidentified nuthatch in Siberian Altay in July 2006.
Dutchbirding 29: 162, 2007
John T Smit, Wolvenstraat 62, 3512 CH Utrecht, Netherlands (jtsmit planet.nl)
Theo Zeegers, Eikenlaan 24, 3768 EV Soest, Netherlands (th.zeegers xs4all.nl)
Esther van den Heuvel, Eikenlaan 24, 3768 EV Soest, Netherlands (e.vdheuvel xs4all.nl)
Bas Roels, Rembrandtkade 57-1, 3583 TR Utrecht, Netherlands (broels xs4all.nl)





In the summer of 2006, Esther van den Heuvel, Bas Roels, John Smit and Theo Zeegers participated in an entomological expedition to the Altay mountains in southern Siberia, more or less on the crossing of China, Kazakhstan, Mongolia and Russia. At one of our campsites, at an altitude of c 2000 m up in the Aktru valley in the central Chuiskiy range, we saw a small nuthatch Sitta which resembled, in our frame of reference, Corsican Nuthatch S whiteheadi. Of course, we knew that this was impossible but with nothing more than a European field guide (Heinzel et al 1996) at hand, we were not able to identify it properly.

The place where we observed the nuthatch was: Aktru, south of Karay, at 2000 m above sea level (50°05’12.2’’ N, 87°46’59.4’’ E), Kosh-Arachskiy Rajon, Respublika Altay, southern Siberia, Russia. This site is a valley at the end of two glaciers, and more or less at the timberline, c 100 km from the Mongolian border. The forest was a pure stand of larch Larix.

Because it turned out that a pair of this nuthatch was breeding in a larch, we saw the species repeatedly. The two were sexually dimorphic: the male had a black cap, whereas the female had no black cap; both had a distinct dark eye-stripe and a white supercilium. These are exactly the features of Chinese Nuthatch S villosa (cf Harrap & Quinn 1996). The underparts, however, showed relatively little buff coloration, as compared with typical villosa.

The only nuthatch species with a distribution that is known to include southern Siberia is Eurasian Nuthatch S europaea (Harrap & Quinn 1996). However, the clear black cap in the male as well as the white supercilium in both sexes and the small size exclude Eurasian.

According to Nazarenko (2006), the distributional area of Chinese Nuthatch is situated somewhere between 33-45° N and 100-133° E. Its breeding range is quite patchy. If the nuthatch we observed was indeed Chinese, then this would be a breeding record far outside its known breeding range. Another possibility is that our nuthatch could represent a new, undescribed Sitta species. At this moment, based on our field observation, this remains an open question. Either way, the discovery of a breeding pair of Sitta (cf) villosa in the Russian part of the Altay mountains remains a surprising discovery and requires further investigations.
Interestingly, nuthatches have something of a reputation when it comes to remaining undiscovered for a long time; the two most recently described new species for the Western Palearctic were both nuthatches: Corsican Nuthatch (described in 1883) and Algerian Nuthatch S ledanti (described in 1976).

Back from a Predicted Climatic Extinction of an Island Endemic: A Future for the Corsican Nuthatch

Barbet-Massin M, Jiguet F (2011) Back from a Predicted Climatic Extinction of an Island Endemic: A Future for the Corsican Nuthatch. PLoS ONE 6(3): e18228. doi:10.1371/journal.pone.0018228

Abstract:
The Corsican Nuthatch (Sitta whiteheadi) is red-listed as vulnerable to extinction by the IUCN because of its endemism, reduced population size, and recent decline. A further cause is the fragmentation and loss of its spatially-restricted favourite habitat, the Corsican pine (Pinus nigra laricio) forest. In this study, we aimed at estimating the potential impact of climate change on the distribution of the Corsican Nuthatch using species distribution models. Because this species has a strong trophic association with the Corsican and Maritime pines (P. nigra laricio and P. pinaster), we first modelled the current and future potential distribution of both pine species in order to use them as habitat variables when modelling the nuthatch distribution. However, the Corsican pine has suffered large distribution losses in the past centuries due to the development of anthropogenic activities, and is now restricted to mountainous woodland. As a consequence, its realized niche is likely significantly smaller than its fundamental niche, so that a projection of the current distribution under future climatic conditions would produce misleading results. To obtain a predicted pine distribution at closest to the geographic projection of the fundamental niche, we used available information on the current pine distribution associated to information on the persistence of isolated natural pine coppices. While common thresholds (maximizing the sum of sensitivity and specificity) predicted a potential large loss of the Corsican Nuthatch distribution by 2100, the use of more appropriate thresholds aiming at getting closer to the fundamental distribution of the Corsican pine predicted that 98% of the current presence points should remain potentially suitable for the nuthatch and its range could be 10% larger in the future. The habitat of the endemic Corsican Nuthatch is therefore more likely threatened by an increasing frequency and intensity of wildfires or anthropogenic activities than by climate change.

Distribution and population size of the Corsican Nuthatch Sitta whiteheadi

THIBAULT J.-C., HACQUEMAND D., MONEGLIA P., PELLEGRINI H., PRODON R., RECORBET B., SEGUIN J.-F., VILLARD P. 2011. Distribution and population size of the Corsican Nuthatch Sitta whiteheadi. Bird Conservation International, 1-8.

Abstract:
Endemic to the island of Corsica in the western Mediterranean, the Corsican Nuthatch Sitta whiteheadi only occupies mature stands of Corsican Pine Pinus nigra laricio which cover a very small area. We present estimates of the distribution and population size of the Corsican Nuthatch, based on both field investigation and analysis of vegetation maps for the 103 county and municipality forests identified. Between spring 1997 and summer 2008, 48 forests were systematically investigated to map nuthatch territories, requiring 20 months of fieldwork. In the 55 forests not explored, we estimated the number of territories from analysis of digital maps with a calculated mean density from six spot-mapping censuses previously made in mature forests. The total estimated number was estimated to be 1,557-2,201 territories, distributed across 45 forest fragments (5 group of connected stands) totalling 185 km2. At distances varying from 250 m to 16 km from each other, fragments were separated by unfavourable vegetation (shrubs, trees other than pines) or rocky outcrops. The area of these fragments varied from seven to 3,159 ha. Of the 45 fragments, 19 held fewer than 10 nuthatch pairs, 20 had 10–99 territories, and only six had more than 100 territories. We suggest that nuthatch numbers have declined by 10% in the past 10 years because of a reduction in suitable habitat due to fires and logging. The Corsican Nuthatch currently fulfils the criteria established by IUCN to qualify as ‘‘Vulnerable’’.

COOPERATIVE BREEDING IN THE BROWN-HEADED NUTHATCH

COX J. A., SLATER G. L. 2007. COOPERATIVE BREEDING IN THE BROWN-HEADED NUTHATCH. The Wilson Journal of Ornithology 119(1):1-8.

Abstract:
We monitored two color-marked populations of the Brown-headed Nuthatch (Sitta pusilla) for ≥5 years and collected data on survival, dispersal, territoriality, and cooperative breeding. Adults (n = 284) were sedentary, maintained long-term pair bonds, and had higher apparent annual survival (66–78%) than previously reported. Territories monitored (n = 347) contained up to five adults; the percentage of territories containing >2 adults averaged 20% but varied widely. Most groups with >2 adults consisted of a breeding pair and a male helper related to at least one breeding adult (n = 8), but several exceptions were noted. The presence of helpers did not improve nest productivity. Apparent annual survival for females was lower than apparent survival for males in one population and may have influenced cooperative breeding. In the other population, apparent survival was similar between males and females. We suggest food resources and other environmental factors may have influenced cooperative breeding in this setting.

Behavior and habitat use of the Brown-headed Nuthatch (Sitta pusilla) in an urban environment

Herb Jr, A. J. 1999. Behavior and habitat use of the Brown-headed Nuthatch (Sitta pusilla) in an urban environment. M.A. Thesis. Stephen F. Austin State University, Nacogdoches, TX.

Orthoskrjabinia rostellata (Cestoidea: Dilepididae), from the brown-headed nuthatch, sitta pusilla (Passeriformes: Sittidae), from Northeastern Texas

MCALLISTER C. T., BURSEY C. R. 2003. Orthoskrjabinia rostellata (Cestoidea: Dilepididae), from the brown-headed nuthatch, sitta pusilla (Passeriformes: Sittidae), from Northeastern Texas. The Texas journal of science, (55)2: 189-191.

Abstract:
The dilepidid tapeworm, Anonchotaenia rostellata (Rodgers 1941) was described from 13 specimens taken from the small intestine of a northern cardinal, Cardinalis cardinalis (Linnaeus) collected at Stillwater, Payne County, Oklahoma, in the spring of 1940 (Rodgers 1941). In 1948, A. rostellaza was transferred to the genus Orthoskrjabinia and is the only North American representative of that genus (see Schmidt 1986). To the authors' knowledge, Rodgers (1941) is the only report of this tapeworm.
This study reports the results of an examination of two brown-headed nuthatches, Sitta pusilla Latham and C. cardinalis.

Relationships Between Habitat and Snag Characteristics and the Reproductive Success of the Brown-headed Nuthatch (Sitta pusilla) in Eastern Texas

Dornak L. L., Burt D. B., Coble D. W., Conner R. N. 2004. Relationships Between Habitat and Snag Characteristics and the Reproductive Success of the Brown-headed Nuthatch (Sitta pusilla) in Eastern Texas. Southeastern Naturalist (9)4: 683-694.

Abstract:
Habitat use and reproductive success of the Brown-headed Nuthatch (Sitta pusilla Latham) were studied in East Texas during the 2001–2002 breeding seasons. We compared nest cavity selection at used and randomly selected non-used areas. Height of nest trees, midstory density, and percent leaf litter were negatively correlated with nest site selection. Brown-headed Nuthatches showed a strong preference for short snags; yet placed their nest cavity entrances near the top of the snags. While nuthatches may be selecting for habitats with little or no midstory density, percent of leaf litter in the nest sites is most likely the consequence of frequent burning. No significant differences among habitat variables and snag characteristics were found between successful and failed nest cavities. Additionally, no habitat variables were correlated with the number of chicks fledged per nest. Predation was the major cause of nest failure in this study.

Brown-headed Nuthatch (Sitta pusilla)

Ghalambor C. K., Martin T. E. 1998. Brown-headed Nuthatch (Sitta pusilla) . The Birds of North America, no. 349, 24 pp.

his species account discusses: distinguishing characteristics, distribution, systematics, migration, habitat, food habits, vocalizations, behavior (locomotion, maintenance, agonistic, sexual, social, interspecific), breeding (phenology, nest site, nest, eggs, incubation, development of the young, parental care), demography and populations (life span, mortality, dispersal and philopatry, population status), conservation and management, plumages and molt, and measurements. There is also a bibliography which lists key references for additional information.

Descriptors: Article Subject Terms Conservation | Demography | Diets | Ecological distribution | Feeding behavior | Life history | Migration | Reproduction | Reproductive behavior | Vocalization behavior | Article Taxonomic Terms Sitta pusilla

Red-breasted Nuthatch (Sitta canadensis)

Ghalambor C. K., Martin T. E. 1999. Red-breasted Nuthatch (Sitta canadensis). The Birds of North America, no. 459, 28 pp.

This species account discusses: distinguishing characteristics, distribution, systematics, migration, habitat, food habits, vocalizations, behavior (locomotion, maintenance, agonistic, spacing, sexual, social and interspecific), predation, breeding (phenology, nest site, nest, eggs, incubation, development of young, parental care, brood parasitism), demography and populations (measures of breeding activity, life span, mortality, dispersal and philopatry, population status), conservation and management, plumages and molt, measurements, and priorities for future research. There is also a bibliography which lists key references for additional information.

Descriptors: Article Subject Terms Agonistic behavior | Breeding | Conservation | Demography | Diets | Dispersal | Feeding behavior | Habitat preferences | Interspecific relationships | Life history | Migration | Philopatry | Predation | Reproductive behavior | Social behavior | Vocalization behavior | Article Taxonomic Terms Sitta canadensis

Predicting distribution, habitat suitability and the potential loss of habitat for Sitta formosa, the beautiful nuthatch

Witt J. C. 2007. Predicting distribution, habitat suitability and the potential loss of habitat for Sitta formosa, the beautiful nuthatch. gradworks.umi.com

Abstract:
The beautiful nuthatch, Sitta formosa, occurs in high-altitude evergreen and semi-evergreen forests throughout the south and southeastern extent of the Himalayan Mountains. Populations of S. formosa are small, declining and severely fragmented as a result of habitat degradation and fragmentation, and therefore it is considered vulnerable by the World Conservation Union and is included in the 2004 Red List of Threatened Species. I used ecological niche factor analysis to model the potential distribution and predict suitable habitat for S. formosa. By using 59 presence locations, collected from museum specimens and biodiversity surveys, and together with topographic and climate variables, I found S. formosa to be linked to much greater than average rainfall and greater than average slopes throughout the study area. S. formosa presence points were highly correlated with mature forests (frequency = 0.86), consisting of evergreen broadleaf, deciduous broadleaf and mixed forests.

Behavior of the giant nuthatch (Sitta magna)

Charonthong, K. Sritasuwan, N. 2009. Behavior of the giant nuthatch (Sitta magna). Research Journal of Biological Sciences (4)11: 1142-1147.

Abstract:
This study describes the foraging and breeding behavior of the Giant Nuthatch (Sitta magna) in Northern Thailand. The study was done in 50×50 m plots where S. magna is usually found in the Chiang Dao Wildlife Sanctuary, Chiang Mai province. Observations were made once per month. The proportion of each direction of foraging and the proportion of tree species used for foraging were compared using binomial test. Breeding behavior was assessed using the focal-scan method on a trail from Den Ya Kad Check Point to San Pa Kiey sub office of Chaing Dao Wildlife Sanctuary, Chiang Mai Province. The tree species used in the test for foraging non-significant proportion of Pinus Kesiya was 0.7 and other species was 0.3 (p=0.487, α=0.05), indicating that S. magna used more proportion of Pinus kesiya than other tree species for foraging. During January and February, about 5-8 S. magna foraged together for courtship and mating. Males followed and tried to fed females. Both males and females shared parental care tasks. S. magna used second cavity in Pinus kesiya, Lithocarpus sootepensis and unknown species dead trees for nests. Nestling left the nest at the average of 22.67 days old (from three nests). It is hoped that this study will be used for education policy making and in implementing action plans for the conservation of birds and biodiversity in this sanctuary.

Type specimens and type localities of rock nuthatches of the Sitta neumayer species complex (Aves: Sittidae)

Mlíkovský J. 2007. Type specimens and type localities of rock nuthatches of the Sitta neumayer species complex (Aves: Sittidae). Journal of the National Museum (Prague), Natural History Series, (176)6: 91-115.

Abstract:
Twenty species-group names were created for Rock Nuthatches of the Sitta neumayer species group in 1790–1950. Their applicability is discussed, their type specimens are identified, and their type localities are specified. Lectotypes were designed for three nominal species, incl. Sitta obscura Zarudnyj & Loudon, 1905, Sitta dresseri Zarudnyj & Buturlin, 1906, and Sitta zarudnyi Buturlin, 1907.

Keywords:
Aves, Sittidae, Sitta, Palearctic, nomenclature.

Predator stimuli and calling behavior of Carolina chickadees (Poecile carolinensis), tufted titmice (Baeolophus bicolor), and white-breasted nuthatches (Sitta carolinensis)

Bartmess-LeVasseur J., Branch C. L., Browning S. A., Owens J. L., Freeberg T. M. 2010. Predator stimuli and calling behavior of Carolina chickadees (Poecile carolinensis), tufted titmice (Baeolophus bicolor), and white-breasted nuthatches (Sitta carolinensis). Behavioral Ecology and Sociobiology, (64)7: 1187-1198.

Abstract:
Evidence from different chickadee species (Poecile genus) indicates that birds can modify the note composition of their “chick-a-dee” calls in the presence of predator stimuli. Here, we tested the effects of predator models and the distance of those models on calls of three species foraging together at feeding stations: Carolina chickadees (Poecile carolinensis) and tufted titmice (Baeolophus bicolor), both members of the Paridae family, and white-breasted nuthatches (Sitta carolinensis), a member of the Sittidae family. Model and distance affected seed-taking rates in all three species. “Chick-a-dee” calling rates were higher in the predator context for both chickadees and titmice, but we detected no predator context effects on “quank” call rates for nuthatches. Predator and distance contexts affected acoustic parameters of notes of the “chick-a-dee” calls of chickadees and titmice; no such effects were detected for nuthatch “quank” calls. These results suggest species differences in encoding of information in the primary social calls of these three species that commonly occur in multi-species flocks. Chickadees and titmice are “nuclear” species and nuthatches are “satellite” species, and these different roles might be related to the differences in vocal signaling that we detected.

Keywords:
Vocal signals, Chick-a-dee calls, Predator, Mobbing, Paridae.

EARLY ARRIVAL OF RED-BREASTED NUTHATCH (Sitta canadensis) IN SOUTHEASTERN NEW YORK DURING SUMMER 2007

Feustel K. 2007. EARLY ARRIVAL OF RED-BREASTED NUTHATCH (Sitta canadensis) IN SOUTHEASTERN NEW YORK DURING SUMMER 2007. The Kingbird, 57 (4): 295-297.

Abstract:
In June and early July of 2007 there were a number of sightings of Red-breasted Nuthatch on Long Island and in New York City. These observations are noteworthy for the early dates of arrival and their occurrence at locations that do not have regularly breeding Red-breasted Nuthatches. The early arrival of Red-breasted Nuthatches in Region 10 is often a harbinger of a fall coastal movement.

HABITAT PARAMETERS AND BREEDING DENSITY OF KRÜPER’S NUTHATCH SITTA KRUEPERI PELZELN IN SOUTHERN TURKEY

ALBAYRAK T., BAIRLEIN F., ERDOGAN A. 2010. HABITAT PARAMETERS AND BREEDING DENSITY OF KRÜPER’S NUTHATCH SITTA KRUEPERI PELZELN IN SOUTHERN TURKEY. Pol. J. Ecol. (58)3: 545-552.

Abstract:
Krüper’s Nuthatch (Sitta krueperi, Passeriformes) is small-area confined species and it mainly occurs in Anatolia in Turkey, but small numbers are found on the adjacent Lesvos Island and the Caucasus region. It is considered as a “near” threatened species by IUCN. Breeding success of Krüper’s Nuthatchs, which use nest cavities excavated by woodpeckers or make their own entrance holes in slightly decayed old tree trunks, is about 72% fledged birds and main food is composed of Coleoptera and Lepidoptera. Although this species is mainly confined to red pine (Pinus brutia) forest, it occurs also in the other coniferous habitats. Krüper’s Nuthatch was surveyed in four regions of Mediterranean Turkey: the Antalya, Central Taurus, Aladağlar region and Amanos Mountains on an area of 27.9 km2. Total of 395 point counts were taken in coniferous forests during the breeding season 2005 to explore the factors which affect the population distribution and density. For each point counts following habitat parameters were measured: (1) height of canopy top, (2) height of canopy bottom, (3) tree diameter at breast height, (4) percentage cover (5) average distance between two trees, (6) total number of strata of vegetation and topographic data (altitude, degree of slope, direction of slope, soil texture). The average density of Krüper’s Nuthatch recorded in the all sites was 7.38 ± 0.57 birds km–2. However, it differs between regions (ANOVA; P <0.0001) with highest density in the Antalya region (12.10 ± 2.10 birds km–2), and a decrease to the east with lowest density in the Amanos Mountains (2.42 ± 0.98 birds km–2). Krüper’s Nuthatch breeding density was higher in high altitude and in black pine (Pinus nigra) forest. The highest mean density was found in black pine forests (12.69 ±2.4 birds km–2; n = 29), followed by Cilician fir (Abies cilicica) forest (11.61 ± 2 birds km–2; n = 39), Lebanon cedar forest (Cedrus libani) (8.49 ± 1.8 birds km–2; n = 25) and red pine (Pinus burutia) forest (7.75 ± 0.9 birds km–2; n = 188) respectively. We also found a negative correlation between the densities of Krüper’s Nuthatch and the total number of strata of the vegetation. High number of the birds occurs in more open coniferous forests. Mature coniferous forests especially black pine forests at high altitudes should be preserved for its conservation in Antalya region.

Keywords:
Krüper’s Nuthatch, Sitta krueperi, distribution, density, Mediterranean region

A model of habitat suitability for Krueper’s Nuthatch Sitta krueperi

ALBAYRAK T., ERDOGAN A., ZIYA FIRATA M. Z. 2011. A model of habitat suitability for Krueper’s Nuthatch Sitta krueperi. Bird Study, 58: 50–56.

Abstract:
Capsule - The presence of Krueper’s Nuthatches can be predicted by variables describing topography, vegetation structure and tree species, and knowledge of these can be used to determine sites for conservation action.
Aim - To analyse the relationships between habitat suitability, as characterized by the presence or absence of Krueper’s Nuthatches, and different predictor variables of forest and landscape diversity by building a logistic regression model.
Methods - We investigated the influence of 11 environmental variables on the occurrence of Krueper’s Nuthatches. Logistic regression, a particular case of GLM with binomial error distribution, was used to identify vegetation and topographical variables that provide an explanation for the presence/absence of Krueper’s Nuthatches in the study region of South Anatolia, Turkey.
Results - Tree height, and north and southeast directions of slope were positively correlated with the probability of occurrence of Krueper’s Nuthatches. Altitude, the presence of Red Pine and Syrian Fir trees, the presence/absence of bushes, and southwest direction of slope were all negatively associated with the occurrence of Krueper’s Nuthatches.
Conclusion - The constructed habitat model could be used to predict locations suitable for the creation of reservoirs for the conservation of Krueper’s Nuthatches in this region of southern Turkey.

Isolation and characterization of polymorphic microsatellite markers for the brown-headed nuthatch (Sitta pusilla)

Haas S. E., Smith J. V., Kimball R. T., Clark M. Isolation and characterization of polymorphic microsatellite markers for the brown-headed nuthatch (Sitta pusilla). Conservation Genetics (10)5: 1393-1395.

Abstract:
Populations of brown-headed nuthatches (Sitta pusilla) are declining throughout the species range. Here we characterize twelve polymorphic microsatellite loci for this species. Analysis of 32 presumably unrelated individuals from a single population revealed an average of 14.9 alleles per locus (range 4–25), an average observed heterozygosity of 0.74 (range 0.52–0.94) and an average polymorphic information content of 0.80 (range 0.57–0.95). We anticipate that these microsatellite markers will be useful for population genetic and behavioral studies on the brown-headed nuthatch and closely related species.

Keywords:
Brown-headed nuthatch, Microsatellites, Passerine, Primers, Sittidae

Fine-Scale Spatial Genetic Structure in the Cooperatively Breeding Brown-Headed Nuthatch (Sitta pusilla)

Haas S. E. Cox J. A., Smith J. V., Kimball R. T. 2010. Fine-Scale Spatial Genetic Structure in the Cooperatively Breeding Brown-Headed Nuthatch (Sitta pusilla). Southeastern Naturalist 9(4):743-756.

Abstract:
Many cooperatively breeding birds exhibit fine-scale spatial genetic structure as a result of restricted dispersal and habitat specialization. Sitta pusilla (Brown-headed Nuthatch) is a cooperatively breeding bird restricted to mature pine-dominated forests of the southeastern United States and has been undergoing population declines across most of its range. We used five polymorphic microsatellite loci developed for this species to examine fine-scale spatial genetic structure within a site in northern Florida as well as broader genetic structure among this site and two other sites (a second in northern Florida and one in southern Georgia). Spatial autocorrelation analyses within the more densely sampled site detected positive spatial genetic autocorrelation up to 1300 m in males when auxiliary males were included, but no autocorrelation was found in females or in males when auxiliary males were excluded. At the broader scale, we found small but significant genetic differentiation among all three populations, including two sites that were separated by less than 40 km of suitable habitat. Our results suggest that both sexes of the Brown-headed Nuthatch exhibit limited dispersal, with philopatric male auxiliaries contributing to more pronounced genetic structure over small geographic distances compared to females. Our sampled populations were in a region where much suitable habitat remains, yet we still observed limited dispersal. This finding suggests that in more fragmented regions, populations may become isolated and at risk of extinction.

Testing hypotheses of Pleistocene population history using coalescent simulations: phylogeography of the pygmy nuthatch (Sitta pygmaea)

Spellman G. M., Klicka J. 2006. Testing hypotheses of Pleistocene population history using coalescent simulations: phylogeography of the pygmy nuthatch (Sitta pygmaea). Proc. R. Soc. B, vol. 273 no 1605: 3057-3063.

Abstract:
In this paper, we use mitochondrial NADH dehydrogenase subunit 2 sequences to test Pleistocene refugial hypotheses for the pygmy nuthatch (Sitta pygmaea). Pygmy nuthatches are a common resident of long-needle pine forests in western North America and demonstrate a particular affinity with ponderosa pine (Pinus ponderosa). Palaeoecological and genetic data indicate that ponderosa pine was isolated in two Pleistocene refugia corresponding to areas in the southern Sierra Nevada in the west and southern Arizona and New Mexico in the east. We use coalescent simulations to test the hypothesis that pygmy nuthatches tracked the Pleistocene history of their preferred habitat and persisted in two refugia during the periods of glacial maxima. Coalescent simulation of population history does not support the hypothesis of two Pleistocene refugia for the pygmy nuthatch. Instead, our data are consistent with a single refuge model. Nucleotide diversity is greatest in the western populations of southern and coastal California. We suggest that the pygmy nuthatch expanded from a far western glacial refuge into its current distribution since the most recent glacial maximum.

Keywords:
coalescent simulations, effective population size (Ne), theta (θ), site-specific mutation rate (μ), pygmy nuthatch (Sitta pygmaea), Ponderosa Pine (Pinus ponderosa).

Ecology of the White-browed Nuthatch Sitta victoriae in Natmataung National Park, Myanmar, with notes on other significant species

Naing T. Z. 2003. Ecology of the White-browed Nuthatch Sitta victoriae in Natmataung National Park, Myanmar, with notes on other significant species. Forktail 19 : 57-62.

Abstract:
Surveys were carried out in temperate pine and oak forest at 2,450–3,054 m in Natmataung National Park, Myanmar during November 2001–July 2002. A total of 197 species were recorded in or around the park, including the Endangered White-browed Nuthatch Sitta victoriae, three Vulnerable species (Mrs Hume’s Pheasant Syrmaticus humiae, Blyth’s Tragopan Tragopan blythii, Grey-sided Thrush Turdus feae), six Near Threatened species and four species recorded for the first time in West Myanmar. The first detailed observations on the ecology, foraging and breeding behaviour of the White-browed Nuthatch were carried out, and three nests were found. Whitebrowed Nuthatches were usually seen alone (66.3% of observations), and mainly in Quercus semecarpifolia trees (50%). Gleaning insects from mosses, lichens and epiphytes was the commonest foraging technique (87.6% of observations).

Red-breasted Nuthatch, Sitta canadensis, Dies Stuck in Resin at Entrance to a Nest-box

Strauss C. F. 2007. Red-breasted Nuthatch, Sitta canadensis, Dies Stuck in Resin at Entrance to a Nest-box. The Canadian Field-Naturalist, 121,4.

Abstract:
I document a female Red-breasted Nuthatch (Sitta canadensis) found dead and stuck to resin in the opening of a nest-box in an urban setting. This is the second reported occurrence of such mortality and the first involving a nest-box. This species applies resin to its nest openings to deter predators and reduce competition or parasitism from other species. Red-breasted Nuthatches infrequently utilize nest-boxes. At necropsy this female nuthatch was found to be carrying a fully-formed egg with shell and this increase in abdominal girth may have contributed to her demise.