Noninvasive genetic analysis in birds: testing reliability of feather samples

Noninvasive samples are useful for molecular genetic analysis of free‐ranging animals. I tested whether moulted feathers collected in the field are a reliable source of DNA for genotyping microsatellite loci. I prescreened extracts for DNA quantity and, using only samples with higher amounts of DNA, obtained reliable genotyping results. Polymerase chain reaction (PCR) amplification success was higher from extracts of plucked feathers than moulted feathers. DNA quantity in larger feathers was higher than that in smaller feathers. This study clearly demonstrates that moulted feathers could be used for genetic studies in birds.     

Crepidolithus cantabriensis nov. sp., a new calcareous nannofossil (Prymnesiophyceae) from the Lower Jurassic of northern Spain

A new calcareous nannofossil, Crepidolithus cantabriensis nov. sp., is described from the Lower Jurassic marls and marly limestones of the Cantabrian Range (Northern Spain). The new species is characterized by medium-sized, normal to narrowly elliptical coccoliths with open central-areas. In the light microscope, under crossed nicols and in distal view, it displays a characteristic bicyclic extinction pattern. Its inner rim edge shows maximum birefringence colours, which vary from white to yellow, whereas the faintly outer rim margin exhibits low birefringence, tending to grey, and they are separated by a dark and sigmoidal isogyre. C. cantabriensis nov. sp. seems closely related to Crepidolithus crassus on the basis of shared morphological characters. Both of them have a distal shield composed of around thirty sub-vertical, dextrally imbricating laths. The central-area width of C. cantabriensis nov. sp. is approximately half of the coccolith width, whilst it is reduced to one or two tiny lenticular slits in C. crassus. Nevertheless, the phyletic relationships between C. cantabriensis nov. sp. and Crepidolithus cavus are not clear, since they show different rim structures, and C. cavus has a delicate bar aligned along the minor axis of its central area. The first specimens of C. cantabriensis nov. sp. have been recognized within the Raricostatum AZ in the Tudanca section. This species seems to be more abundant in the Reinosa area, which occupied a more distal position with respect to the Iberian Massif during the studied time interval. It is hypothesized here that C. cantabriensis nov. sp. could have inhabited the lower-photic zone.     

Deciphering archaeological palimpsests with bone micro-fragments from the Lower Magdalenian of El Mirón cave (Cantabria,Spain)

Abstract

Modern excavation techniques aim accurately to recover extant archaeological data. Usually bone micro-fragments are gathered as a result, however, during archaeological analysis these remains are often set apart as indeterminate bones and generally do not contribute to the interpretation of the deposits. How to decipher archaeological palimpsests using these small bone fragments is the aim of this paper. El Mirón Cave, located in northern Iberia, contains a very rich Cantabrian Lower Magdalenian deposit (17–15 uncal ka BP) with high densities of faunal remains and artefacts. Here, we present zooarchaeological, taphonomic and spatial distribution analyses of macromammal finds, including those small bone fragments, accumulated during a series of intensive and repeated human occupations found in the outer vestibule excavation area. Our results show that a broad spectrum of activities was performed there, including meat, marrow and grease processing and waste abandonment. We propose that bone micro-fragments must be considered when addressing human subsistence reconstructions from animal remains, as they represent the leftovers of the chaîne opératoire of animal carcass exploitation. The archaeological implications of their inclusion are extremely valuable, especially when deciphering palimpsests. A multidisciplinary approach to study these small animal remains provides information that otherwise would be missed.     

Wildlife habitat analysis – a multidimensional habitat management model

In intensively cultivated landscapes, the effects of land use – changing habitat quality and habitat availability - on wildlife populations are of major importance for wildlife management. Populations of some species reach high densities, grow rapidly, and can therefore cause damage to tree regeneration in forests; chamois (Rupicapra rupicapra) is an example. Other species, like capercaillie (Tetrao urogallus), suffer from substantial habitat loss resulting in a population decline. Consequently, the number of individuals and the quality of habitat are of crucial relevance for the development of wildlife management concepts. It is critical to know, which areas provide suitable habitat conditions for a species, and what quantity and quality of habitat is required to achieve a certain population size.

In order to evaluate habitat quality and to link wildlife research to practical habitat management, an integrated habitat management model has been designed. The model is based on a multi-dimensional habitat analysis which employs different methodological levels, which were defined according to different spatial scales. On a country scale (level 1), the wildlife ecological landscape type (WELT) is introduced. For this study the federal state of Baden-Wuerttemberg is divided into units which represent distinct regions with similar landscape ecological habitat conditions for wildlife species. On an eco-regional scale (level 2), the landscape ecological habitat potential (LEHP) was developed. It is based on the evaluation of species-related landscape parameters within an exemplary eco-region and provides information about the potential habitat available to a population. On two local scales (level 3: forest district, level 4: forest stand), a habitat structure analysis was conducted, which serves as a foundation for habitat improvement and the monitoring of habitat conditions. The three methodological elements WELT, LEHP and habitat structure analysis were integrated into a habitat management model. The model uses chamois and capercaillie as examples, but can be equally applied to other species and wildlife management regimes.     

Genotyping faeces reveals facultative kin association on capercaillie’s leks

The role that kin selection might play in the evolution of lekking in birds remains controversial. Recent molecular data suggest that males displaying on leks are related. Here we investigated the genetic structure and pattern of relatedness on leks of a declining population of capercaillie (Tetrao urogallus) using microsatellite genetic markers. Since the species is highly sensitive to disturbance, we adopted a non-invasive method by using faecal samples collected in the field. Based on a dataset of 50 males distributed in 6 sub-populations, we found significant genetic structuring among sub-populations, and a significant pattern of isolation by distance among leks. Estimates of relatedness showed that males displaying on the same lek were related, even when controlling for the effects of genetical differentiation among sub-populations. In addition, the frequency distribution of relatedness values indicated that leks contain a mixture of close kin and unrelated individuals (34 and 66%, respectively). This pattern is consistent with the hypothesis that leks often contain kin associations, which might be due to very restricted dispersal of some of the males or to joint dispersal of kin. The results are discussed with respect to their implication for the conservation of endangered populations.     

The Late Holocene extinction of Pinus sylvestris in the western Cantabrian Range (Spain)

Aim To reconstruct the historical biogeography of Pinus sylvestris in the Cantabrian Range (Iberian Peninsula) during the Holocene, and to consider the interactions between vegetation dynamics, climate change and the role of man in the present‐day distribution of the species. Location The study site is a mire (1300 m a.s.l.) at Vega de Viejos, on a south‐facing slope of the western Cantabrian Range, Spain. The region’s present‐day landscape is almost treeless, with the exception of some patches of Quercus pyrenaica and a few copses of Salix and Betula along stream banks. Methods Tree macrofossils from Vega de Viejos were studied by transmitted light and dark‐field reflection microscopy; strobili were subjected to comparative morphological analyses. Two Pinus macrofossils were dated by conventional ¹⁴C methods. Results The taxonomic accuracy achieved in the identification of the macrofossils provided new information regarding the Holocene history of Pinus sylvestris in this territory. Ninety‐five cones of this species were identified; in fact, more than 80% of the 36 identified wood remains were of Pinus gr. sylvestris. Radiocarbon dating revealed that the forest to which the fossils belonged was present until at least 2170 ± 50 yr bp – its disappearance was therefore relatively recent. Main conclusions Pinus sylvestris suffered long‐term isolation, and after the Würm glacial period tended to migrate towards the east. In western Iberia, a temperate climate and autogenic succession favoured broadleaved taxa at the expense of Pinus. Late Holocene human disturbances may have further accelerated the decline of P. sylvestris; in the Cantabrian Range, only a few stands on southern slopes have persisted until the present day. The history of the capercaillie (Tetrao urogallus), a bird characteristic of pure or mixed Palaeartic coniferous forests, was almost certainly affected by the demise of these forests in this area. Cantabrian capercaillies are the only members of this species that live in purely deciduous forests, perhaps a recent adaptation to the regional extinction of pines. Today’s P. sylvestris and capercaillie populations are now highly fragmented and their future, given the predictions of global climate change, is uncertain.     

Capercaillie in the Alps: genetic evidence of metapopulation structure and population decline

In the Alps, the capercaillie is distributed in a metapopulation pattern with local populations on mountain ranges separated by farmland valleys. Habitat deterioration, primarily related to human land use, resulted in population declines and range contractions became obvious. At the edge of a species' range, lower connectivity and less gene flow may render populations more susceptible to decline and extinction than in the core of the range. If this were true for the capercaillie in the Alps, edge populations should be subject to limited gene flow and should show genetic signs of a more severe population decline than core populations. To test this hypothesis, we used microsatellite DNA typing techniques. We assessed genetic variation within and among 18 local capercaillie populations across the Alps in relation to geographical distribution within the metapopulation system. All populations showed high levels of genetic variation in terms of average number of alleles, allelic richness and heterozygosity. Excess heterozygosity suggested a recent population decline, that was more pronounced in edge than core populations. We found high gene flow, but also significant differentiation among populations. Differentiation among edge populations was related to geographical distance, and appeared to be a recent process, most probably caused by reduced gene flow after population decline. In the core group, the high mountains of the central Alps seem to limit dispersal, and genetic drift was the most likely explanation for the observed differentiation among populations. We conclude that maintaining connectivity within the metapopulation system is vital for capercaillie conservation in the Alps.     

Effects of Recreation and Hunting on Flushing Distance of Capercaillie

Abstract: The capercaillie (Tetrao urogallus) in Central Europe is an endangered species of grouse that is thought to be highly susceptible to human disturbance, possibly causing local populations to decline. We investigated the behavioral response of capercaillie in the Black Forest, Germany, and the French Pyrenees to an off-trail hiker by measuring flushing distances. Flushing distance varied with capercaillie sex, visibility of the hiker, intensity of winter tourism, and hunting pressure. Independent of the study area, males flushed at consistently longer distances than females, and lower visual blocking between bird and hiker resulted in longer flushing distances. Capercaillie flew at longer distances from an approaching hiker in areas with high intensity of winter tourism or hunting pressure than in undisturbed areas. We recommend the establishment of regulations requiring hikers to stay on trails and to close trails where intertrail distances fall below 100 m (90% of all flushing events appeared within 50 m). Furthermore, planting or preserving evergreen conifer trees in dense rows along critical parts of disturbance sources, reducing the degree of visibility between capercaillie and recreationists would increase habitat for capercaillie in forests with predictable recreation activities.