Genetic monogamy in single-male groups of acorn woodpeckers, Melanerpes formicivorus

Acorn woodpeckers have one of the most complex social systems of any bird species. Breeding units range in size from monogamous pairs to groups of 15 birds that include multiple breeding males and females as well as nonreproductive helpers-at-the-nest. Groups form when young remain at their natal nest to help their parents breed or when single-sex coalitions of siblings disperse to fill a reproductive vacancy on another territory. Plural breeding and helping behaviour are thought to be favoured through indirect fitness benefits for individuals that would otherwise be unable to breed due to a shortage of reproductive vacancies on territories with acorn stores. We report the results of multi-locus DNA fingerprinting of 51 offspring from 18 nests of 16 socially monogamous pairs of acorn woodpeckers. If socially monogamous females mate outside the pair-bond, indirect fitness benefits for cobreeders and helpers will be significantly reduced. Monogamous pairs accounted for all but one of the 51 offspring we tested; the single exception was apparently sired by the putative father, but the putative mother was excluded from maternity. Our results indicate that individuals remaining on their natal territories as helpers are generally the genetic offspring of the pair they help. They also suggest that single-sex coalitions offspring dispersing together from nests of socially monogamous pairs will be full-siblings.     

Short‐distance migration of Wrynecks Jynx torquilla from Central European populations

European Wrynecks Jynx torquilla torquilla have generally been considered to be long‐distance Palaearctic–African migrants that spend the non‐breeding season in Sahelian Africa, where they have been reported regularly. Results from tracking individual birds showed that Wrynecks from two Central European populations migrated only relatively short distances to the Iberian Peninsula and northwestern Africa (c. 1500 km and 3000 km, respectively), compared with a minimum distance of about 4500 km to Sahelian Africa. Additionally, differences in wing lengths of populations from Central and Northern Europe support the idea of leap‐frog migration, populations from Northern Europe being long‐distance migrants with a non‐breeding distribution in Sahelian Africa.     

Red-Headed Woodpecker Nest-Habitat Thresholds in Restored Savannas

Abstract: The red-headed woodpecker (Melanerpes erythrocephalus) is a widespread, adaptable species that continues to decline across North America. We examined stand, nest-tree, and cavity characteristics of red-headed woodpeckers in restored savannas within the Necedah National Wildlife Refuge, Wisconsin, USA, during 2002 and 2003. Based on availability, red-headed woodpeckers selected snags and trees with greater dead limb length. Red-headed woodpeckers nested in areas with greater basal area, cavity density, snag density, limb-tree density, and total dead limb length. Red-headed woodpeckers exhibited a decadent-tree threshold that was most accurately measured by the number of trees with dead limbs around (0.04 ha) nests. We found that the probability of a red-headed woodpecker nest being present greatly increased above the decadent-tree threshold. Woodland managers throughout the red-headed woodpecker's extensive breeding range can use our results and recommendations to guide decadent-tree retention for this species.     

PERMANENT GENETIC RESOURCES: Isolation and characterization of 12 microsatellite markers in the middle-spotted woodpecker (Dendrocopos medius)

Twelve polymorphic microsatellite loci were developed for Dendrocopos medius. Polymorphism was assessed for 27 individuals from the southwesternmost population of this woodpecker species. The number of alleles per locus ranged from three to seven, with observed heterozygosity values from 0.444 to 0.852. Genotypic frequencies conformed to Hardy-Weinberg equilibrium, and no evidence for linkage disequilibrium was observed. Multilocus genotypes resulting from this set of markers will be useful to determine genetic diversity and differentiation within and among habitat patches inhabited by D. medius. Three of the loci were polymorphic for Picoides articus.     

Nuthatch uses tool in London park

Here, we report an observation of a Eurasian nuthatch Sitta europaea foraging with a tool in a public park in Greater London, UK. This record is of significance, as it provides the first photographic evidence (to our knowledge) of nuthatch tool use, reveals an unusually wide phylogenetic and geographic distribution of tool behaviour within the Sittidae, and constitutes a rare example of animal tool use in an urban environment. To improve our understanding of nuthatch tool behaviour, we are building a global database of relevant anecdotal field observations—submissions are most welcome.     

Simulations inform design of regional occupancy‐based monitoring for a sparsely distributed,territorial species

Sparsely distributed species attract conservation concern, but insufficient information on population trends challenges conservation and funding prioritization. Occupancy‐based monitoring is attractive for these species, but appropriate sampling design and inference depend on particulars of the study system. We employed spatially explicit simulations to identify minimum levels of sampling effort for a regional occupancy monitoring study design, using white‐headed woodpeckers (Picoides albolvartus), a sparsely distributed, territorial species threatened by habitat decline and degradation, as a case study. We compared the original design with commonly proposed alternatives with varying targets of inference (i.e., species range, space use, or abundance) and spatial extent of sampling. Sampling effort needed to achieve adequate power to observe a long‐term population trend (≥80% chance to observe a 2% yearly decline over 20 years) with the previously used study design consisted of annually monitoring ≥120 transects using a single‐survey approach or ≥90 transects surveyed twice per year using a repeat‐survey approach. Designs that shifted inference toward finer‐resolution trends in abundance and extended the spatial extent of sampling by shortening transects, employing a single‐survey approach to monitoring, and incorporating a panel design (33% of units surveyed per year) improved power and reduced error in estimating abundance trends. In contrast, efforts to monitor coarse‐scale trends in species range or space use with repeat surveys provided extremely limited statistical power. Synthesis and applications. Sampling resolutions that approximate home range size, spatially extensive sampling, and designs that target inference of abundance trends rather than range dynamics are probably best suited and most feasible for broad‐scale occupancy‐based monitoring of sparsely distributed territorial animal species.     

New Record of Feather Mite,Neopteronyssus bilineatus Mironov, 2003 (Arachnida: Pteronyssidae), from a Grey-Capped Pygmy Woodpecker,Yungipicus canicapillus in Republic of Korea

This study intended to record a species of feather mite, Neopteronyssus bilineatus Mironov, 2003, (Arachnida: Pteronyssidae), from a grey-capped pygmy woodpecker, Yungipicus canicapillus (Blyth, 1845), in the Republic of Korea. Mite samples were collected from the flight feathers of a woodpecker, preserved directly in 95% ethyl alcohol, and then observed by a light microscope after specimen preparation. Morphology of Neopteronyssus bilineatus is distinguished from other pici group species by opisthosoma part with 2 longitudinal bends, tarsal seta rIII 3 times longer than tarsus III in males, and 2 elongated hysteronotal plates extending beyond the level of setae e2 in females. In the present study, a species of feather mite, N. bilineatus, was newly recorded from Y. canicapillus in Korean fauna.     

Isolation and characterization of polymorphic microsatellite loci for the northern flicker (Colaptes auratus; Aves)

To investigate the mating system of northern flickers (Colaptes auratus), we developed primers for 14 microsatellite loci and screened them in 68 unrelated adults and their offspring. All markers were highly polymorphic with 9 to +36 alleles per locus. One marker was Z‐chromosome linked; one marker exceeded the size standard range and could not be analysed further. We checked the other 12 markers for Mendelian inheritance in 36 broods for which the social parents were known. Seven markers showed evidence for the presence of null alleles, and three of those showed significant deviation from Hardy–Weinberg equilibrium. Markers were generally unlinked.