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We studied the relationship between landscape composition and capercaillie density in 50 km × 50 km grids in Finland, where modern forestry started in the 1950s and most of the forests are in commercial use. Capercaillie density was positively associated with the young thinning stand proportion throughout the country, but unlike in numerous older studies, it wasn't positively associated with the mature stand proportion in any part of the country. In central Finland this relationship was even negative. In central and southern Finland capercaillie density was associated positively with the forest land proportion, and negatively with the open area proportion. Results suggest that the overall amount of the forest cover is important for the capercaillie, and that clear-cut areas in the 1950s and 1960s, known as ‘large age classes’, have developed as suitable for them. A new aspect based on results is the potential reduction in the mature forest quality as capercaillie habitats.
While the non-random capture of prey by predators is well-known, few studies have investigated or compared the individual characteristics of prey selected by predators. This is due to the difficulty in assessing prey features based on the remains from pellets or faeces. This article shows relationships between craniometric features and body mass of the root vole (Microtus oeconomus). The comparisons involved 10 skull parameters: mandible length excluding incisors (ML), rostrum breadth (RB), mandibular tooth-row length (MT), foramina incisiva length (FI), upper- and lower-incisor lengths (UIL, LIL), upper- and lower-incisor breadths (UIB, LIB), upper- and lowerincisor weights (UIW, LIW). From cranial parameters listed above, only UIL was correlated with body mass with high accurancy. In this reason we highly recommended this parameter as a good indicator for calculating vole body mass.
Twenty-eight polymorphic microsatellite markers for Japanese sea urchin (Strongylocentrotus intermedius) were developed from the EST database of a related species purple sea urchin (S. purpuratus). The characterization results showed the moderate polymorphisms at these loci. The number of alleles ranged from 2 to 5, and the values of Ho and Hc varied from 0.0667 to 0.9655 and 0.0655 to 0.7350, respectively. No significant linkage disequilibrium (LD) between pairs of loci was found and 21 loci conformed to the Hardy-Weinberg equilibrium (HWE). The results in this study well demonstrated the feasibility of microsatellite marker development via mining EST database of a genetically related species.
The subject of the research was the geographic variation in tooth size and condylobasal skull length (CBL) in arctic fox Vulpes (Alopex) lagopus. The analysis was based on 328 skulls of individuals from 14 different populations. Most of the metric dental characteristics and CBL indicated a significant diversification among the populations. A particularly high inter»population variations was observed in the sizes of C1, C1, P4, and in the CBL. The arctic foxes of Eurasia were larger than the arctic foxes of North America. The largest specimens of the arctic fox were those of Komandorskiye Ostrava, while the smallest ones were on Baffin Land and Greenland. Moderate sizes of dentition and skulls were observed in continental populations (Taymyr, Ust-Yanskiy region, Zaliv Kozhevnikova, Yamal Poluostrov, Yakutskaya oblast'). As regards the variation in the size of the skull and dentition of arctic foxes, a higher variation was noted in arctic foxes from island (St. Lawrence Island, Komandorskiye Ostrava) and “coastal” populations (Yamal Poluostrov, Taymyr), and a lower one in arctic foxes from Asian populations (Zaliv Kozhevnikova, Yakutskaya oblast'). In the Arctic, within the geographical range of the fox, neither the size, nor sexual dimorphism of the metric dental and skull characteristics showed any specific geographic trend. However, the existing hypothesis, (such as Bergmann's rule, or “island syndrome”), do not explain the pattern of size variation in the arctic fox. The arctic fox morphological variation within its range is primarily shaped by climate conditions and food resources, and secondarily by competition within- and between species.
Maculinea nausithousis the most endangered Iberian butterfly, being included in the Bern and Habitat directives and in the Spanish Red Book for invertebrates. We map its potential distribution in the Iberian Peninsula, identifying potentially suitable areas where to focus future surveys. Using presence/absence data and a set of environmental variables, the distribution of M. nausithous was modelled using Generalized Additive Models. Model results were filtered using land cover data to identify the anthropogenic grasslands inhabited by the species. The model obtained indicates that some Iberian areas that currently do not support M. nausithous populations could be environmentally suitable for the species. The reasons for these absences are discussed. Indeed, field surveys identified possible sources of uncertainty at finer scale, highlighting that deficiencies in land use GIS data might constitute an important source of error, able to explain both commission and omission errors (i.e., over and underpredictions) of the model.
The ground parrot (Pezoporus wallicus) is a vulnerable species that occurs in isolated pockets of heathland and sedgeland of Australia. This study used randomly amplified DNA fingerprinting (RAF) to examine genetic diversity in the eastern population of the ground parrot. The seven primers used produced an average of 68 markers per primer, and the number of unambiguous polymorphic markers per primer averaged 6.3 (9.2%). Overall genetic similarity was 0.978 ± 0.03. The low level of genetic diversity revealed by RAF is comparable to the lower end of diversity found in species that are declared endangered.
Allozyme electrophoresis is a common tool to analyse the genetic structure of populations with a focus on conservation and biogeography. An essential requirement for biogeographical analyses is the independence of the applied methods from ecological selection processes. We surveyed the genetic population structure of Coenonympha pamphilus as a model species to validate allozym electrophoresis as a method for such studies. We analysed 106 individuals of C. pamphilus of the Monte Baldo region (southern Alps, Italy) at different altitudes and 82 individuals from two populations north of the Alps (Germany). The FST among all populations was 9.7% but no significant differentiation was observed along the altitudinal gradient in the Monte Baldo region. Our results revealed no influence of the climate on the allozyme frequencies, thus excluding a major importance of recent selection processes for the observed differentiations. These results support the suitability of allozyme electrophoresis for biogeographical studies.
We investigated the response of litter-dwelling arthropods to the effects of four forestry thinning intensities (Control, Light Thin, Light Thin with Gap, and Heavy Thin). With the balance between timber demand and maintaining biodiversity in the forest ecosystem in mind, we examined the effects of thinning on the abundance, richness, and diversity of arthropods as an indicator of how ecological processes affect forest litter-dwelling fauna. Study sites were 40- to 60-year-old stands of typical Douglas-fir plantation in the Willamette National Forest, Oregon, USA. To examine the seasonal response of the litter-dwelling arthropods, litter debris and humus samples were collected in October 2000 (wet late-growing season, Late 2000), June 2001 (wet early-growing season, Early 2001), and August 2001 (dry mid-growing season, Mid 2001) and extracted with Tullgren funnels. The abundance and diversity of litter-dwelling arthropods decreased as thinning intensity increased. The decreases in both abundance and diversity of arthropods with limited mobility within the two heaviest thinnings were correlated with an increased heterogeneity of disturbance to the forest floor (patchy litter and moss cover removal), rather than responses to thinning itself at the scale of the entire stand. The litter-dwelling fauna correlated positively with litter moisture. Under control conditions, the abundance of predators and detritivores increased during the dry summer in August. Non-metric multidimensional scaling results showed distinct clusters for the three growing seasons. The wet early-growing season clustered with the dry mid-growing season, but not with the wet late-growing season. Moisture correlated highly with the ordination axes. This study showed that litter-dwelling arthropods were correlated with stand density and seasonal litter moisture of the forest floor.