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Deciphering the effects of climatic conditions on population dynamics is of major importance in understanding how organisms are likely to be affected by climate changes. Using data from broad-scale annual censuses between 1990 and 2007, we show that winter and summer North Atlantic Oscillations affect several breeding success indicators of the Black Grouse ( Tetrao tetrix) in the French Alps. We did not find any trend in hen counts or breeding indexes over the study period. Surprisingly for a bird specialised in cold climates, we show that Black Grouse optimise their reproductive output for positive values of the winter NAO corresponding to the average NAO index of the last 30 years. Extreme NAO values lead to lower breeding success, indicating that the grouse may be more able to track trends in climate than an increase in the frequency of extreme years. Our result show that, at least from a short-term perspective, Black Grouse productivity is not threatened by a trend towards warmer climatic conditions in the Alps, but may be affected by an increased frequency of extreme years. We advocate the use of the NAO as a climate proxy rather than using heavily noised and biased local climate descriptors in studies focusing on the global response to climate over a large spatial scale. [ABSTRACT FROM AUTHOR] more...

The article presents a study which determines measures to mitigate anthropogenic disturbance among wintering Black Grouse and mountain ecosystems. It outlines the method of the study which applies spatial modeling to localize conflict zones and estimate the amount of habitat reduction caused by winter sports and recreation activities. The study found out the effectiveness of spatial modeling to accurately identify zones of potential conflict to help create measures to minimize such risks. more...

isted reproductive technologies can be an important part of programs directed for maintenance and protection of genetic variability. The objective of this study was to develop methods for liquid storage and cryopreservation of semen capercaillie and black grouse semen. Our results provide for the first time evidence for successful short-term storage and cryopreservation of capercaillie and black grouse semen using criteria of sperm motility characteristics as quality indices. Sperm motility could be protected up to 48 h liquid storage; however, 24-h storage should be preferable. Cryopreservation secured 40-60% post-thaw motility (as compared with control), both for freshly collected and 24-h-stored semen. In conclusion, a procedure for short-term and cryopreservation of capercaillie and black grouse semen are now available. These assisted reproductive technologies can be implemented into captive breeding programs for these species. [ABSTRACT FROM AUTHOR] more...

In northern England, 95% of black grouse Tetrao tetrix leks occur on the fringes of managed grouse moors. Recognising the threatened conservation status of black grouse in northern England, most grouse moors have refrained from deliberate shooting for more than a decade. Despite this, black grouse are unintentionally shot in mistake for red grouse Lagopus lagopus scoticus. We assessed the circumstances and frequency of shooting in northern England and its potential impact on population recovery from three independent sources, annual shooting returns as part of the Game and Wildlife Conservation Trust's (GWCT) National Gamebag Census (NGC), incidents of shooting reported independently to the North Pennines Black Grouse Recovery Project (NPBGRP) and losses of radio-tagged black grouse to shooting. Moors contributing to the NGC between 1998 and 2008 reported 110 black grouse shot from 13 of 23 moors, averaging 1.2% of the estimated post-breeding population. From 2001 to 2008, 152 black grouse from 28 moors were reported shot independently to the NPBGRP, equivalent to an annual 1.0% of the post-breeding population. The majority appeared unintentional (78%), with females (68%) more frequently shot. Out of 244 radio-tagged black grouse on 15 estates, four adult females were shot (1.6%). The voluntary restraint from harvesting black grouse in northern England appears effective, with incidents of shooting infrequent. Continued effort to minimise shooting incidents, particularly on the fringe of the range to encourage settlement of dispersing females, may contribute to increasing numbers and range. [ABSTRACT FROM AUTHOR] more...

Here, we describe genetic diversity of lekking and non-lekking populations of Black Grouse Tetrao tetrix in the mountains bordering the Czech Republic. In total, 250 individuals from eight lekking and eight non-lekking study sites were genotyped at 11 microsatellite loci. Significant pair-wise F values between the different regions indicated low dispersal between localities, and birds could be assigned to three main mountain ranges (Šumava Mts, Krkonoše Mts and Krušné Mts). We found lower genetic diversity at study sites with solitary displaying males compared to sites where birds aggregate at leks. Additionally, genetic diversity was significantly more strongly associated with type of display than with spatial location of the sites. Given that lekking behaviour may be related to population density, we suggest that a shift from lekking to solitary displaying males is an alarming sign for conservationists indicating decreasing effective population sizes and declining populations. [ABSTRACT FROM AUTHOR] more...

The black grouse is an endangered and vulnerable species in several of Europe's countries. From Hungary they became extinct in the 19th century. Their last occurrence was reported in the Nyirseg area, where we have dealt since 2006 with keeping these birds in artificial conditions and breeding them on behalf of the species reintroduction, in the area of the NYÍRERDO Forestry. The breeding stock originates from Germany. Over the course of the last few years we could follow the efficiency of lekking and reproduction. In 2009 we have already closed the third successful breeding period: 169 eggs came from the breeding farms. In this study we summarise our breeding results between 2007 and 2009. Our work enables us to possess a stable bird stock within a few years, which contributes to saving this species. [ABSTRACT FROM AUTHOR] more...

In black grouse Tetrao tetrix the survival of juveniles from hatching until recruitment is a critical determinant of population growth. The proportion of juvenile survivors from hatching until recruitment declines continually, but juvenile mortality rates are commonly highest during approximately the first 10 days after hatching. Likely causes of mortality include adverse weather, predation and availability of food. Little is known, however, about how individual properties, such as body mass of hen or chicks and properties of the brood rearing environment (e.g. vegetation characteristics or weather conditions) interact with each other and/or with fluctuating levels of predator abundance in determining early brood survival, simply because such data are very scarce. Using an information-theoretic approach, our paper identifies determinants of early daily survival rates of black grouse chicks in a managed forest landscape of central Finland. During the three years of our study, the proportion of hens losing their broods within 10 days after hatching varied between 0.08 and 0.36.The variation in daily survival rates of chicks was largely mediated by a combination of four key explanatory variables. Brood survival clearly increased with the extent of bilberry Vaccinium myrtillus cover, and was further affected by interactions of temperature and hatching date as well as temperature and chick body mass. Low temperatures consistently resulted in lower daily survival rates. An increase in temperature, however, was more beneficial for early hatchers and heavy chicks. There was no difference in survival between broods from yearling and adult hens and we found no effect of predator density, be it as main effect or as interaction with other variables, on the daily survival rates of chicks. Improving black grouse breeding success can be regarded as a key management target which may be critical for their recovery. Our results suggest that such management should favour protection or local recovery of bilberry, as well as integrate weather and climate changes into the equation of hunting management. [ABSTRACT FROM AUTHOR] more...

Computational studies have suggested that η3-lithium enolates in which the cation is partially bound to both carbon and oxygen may be important reactive intermediates. DFT calculations are used to demonstrate that explicitly solvated acetone enolates are largely O-bound. With this premise in mind, the stereochemical course of intermolecular Michael additions is examined. The results are generally consistent with what is observed experimentally and the model advanced by Heathcock and co-workers. [ABSTRACT FROM AUTHOR] more...

The article discusses a study on maternal and environmental determinants of daily nest survival rates under variable predator densities of individual black grouse hens in central Finland. It states that predation was the reason behind the net loss and of reproductive failure in all studied cases. It has been shown that breeding individuals may perceive predation risk and adapt reproductive investment and nest site selection accordingly. more...

Declines of Alpine black grouse Tetrao tetrix populations have been linked to increasing disturbance by recreation and degradation of breeding habitat due to changes in land-use, especially abandonment of traditional farming practices. Appropriate forest, shrubland and grassland management may mitigate the negative effects of land abandonment. The habitat associations and trophic requirements of brood-rearing Alpine black grouse hens were appraised to inform effective habitat management policies. We measured the abundance, biomass and phenology of arthropods, a key food source for grouse chicks, in eight timberline habitat categories and performed a habitat selection analysis based on radio-tracking data collected from eight brood-rearing hens in the Swiss and Italian Alps. Arthropod biomass differed significantly between habitat categories and peaked in early summer due to a sharp increase of orthopterans (Saltatoria), an essential food source for Alpine black grouse chicks. Open grassland and grassy shrubland yielded the highest arthropod biomass, with Saltatoria dominating the sample. Yet, brood-rearing hens avoided open grassland, opting for a mosaic of grassy shrubland with scattered trees. Chick- rearing hens apparently traded-off food abundance for reduced predation risk, i.e. habitats offering cover for concealment and escape from predators. These specific black grouse breeding habitat requirements inform about habitat management within Alpine timberline ecosystems. Managers should not restore extensive, homogeneous pasturelands. Instead, a complex heterogeneous habitat mosaic, consisting of patches of grassland and shrubland interspersed with scattered coniferous trees should be promoted. [ABSTRACT FROM AUTHOR] more...

The article presents a study which examined the exact times of mating and hatching in black grouse or Tetrao tetrix and capercaillie or Tetrao urogallus at Varaldskogen in southern Norway. An examination of the relationship between breeding and chick food is included in this study. The study area, methods used in monitoring the birds, aging of chicks and sampling of larval food items are also described. more...

The article presents a study that examined the flocking behavior of Black Grouse during the non-breeding period in open habitats of the Kotlina Orawsko-Nowotarska valley in southern Poland. Focal to the study are the mechanisms of sex-specific and mixed flock formation. Four seasons are used to categorize the results, such as autumn, early winter, winter, and early spring. The authors of the study discovered no difference in mixed flock size among the defined seasons but the mixed flock size decreased as the seasons progressed. more...

Although inbreeding depression and mechanisms for kin recognition have been described in natural bird populations, inbreeding avoidance through mate choice has rarely been reported suggesting that sex-biased dispersal is the main mechanism reducing the risks of inbreeding. However, a full understanding of the effect of dispersal on the occurrence of inbred matings requires estimating the inbreeding risks prior to dispersal. Combining pairwise relatedness measures and kinship assignments, we investigated in black grouse whether the observed occurrence of inbred matings was explained by active kin discrimination or by female-biased dispersal. In this large continuous population, copulations between close relatives were rare. As female mate choice was random for relatedness, females with more relatives in the local flock tended to mate with genetically more similar males. To quantify the initial risks of inbreeding, we measured the relatedness to the males of females captured in their parental flock and virtually translocated female hatchlings in their parental and to more distant flocks. These tests indicated that dispersal decreased the likelihood of mating with relatives and that philopatric females had higher inbreeding risks than the actual breeding females. As females do not discriminate against relatives, the few inbred matings were probably due to the variance in female dispersal propensity and dispersal distance. Our results support the view that kin discrimination mate choice is of little value if dispersal effectively reduces the risks of inbreeding. [ABSTRACT FROM AUTHOR] more...

The article discusses a study on the habitat selection by grouse hunters and the habitat preferences of black grouse and capercaillie in Østfold County, Norway based on a satellite-based dataset of the hunters' movements. The entire track of the hunters was recorded using a handheld global positioning system (GPS). A total of 102 capercaillie and 112 black grouse flushes were observed by the hunters. The habitat selectivity of hunters and the animals was found to be varied. Hunters were said to be less homogenous in their selection than predicted. more...

Different species in a given site or population of a given species in different sites may fluctuate in synchrony if they are affected similarly by factors such as spatially autocorrelated climate, predation, or by dispersal between populations of one species. We used county wise time series of hunting bag records of four Norwegian tetraonid species covering 24 years to examine patterns of interspecific and intraspecific synchrony. We estimated synchrony at three spatial scales; national, regional (consisting of counties with similar climate), and county level. Ecologically related species with overlapping distributions exhibited strong synchrony across Norway, but there was much variation between the different regions and counties. Regions with a long coastline to both the North Sea and the Norwegian Ocean exhibited an overall stronger synchrony than those consisting of more continental areas. Intraspecific synchrony was generally low across all counties, but stronger synchrony between counties within regions defined by climatic conditions. Synchrony was negatively related to distance between populations in three of four species. Only the synchrony in willow ptarmigan showed a clear negative relationship with distance, while the other species had both strong positive and negative correlations at short distances. Strong interspecific synchrony between some species pairs within regions and weak intraspecific synchrony across counties within regions suggest a stronger synchronizing effect from environmental factors such as weather or predation and less effect from dispersal. Our results suggest that the complete tetraonid community is structured by environmental factors affecting the different species similarly and causes widespread interspecific synchrony. Local factors affecting the population dynamics nevertheless frequently forces neighbouring populations out of phase. [ABSTRACT FROM AUTHOR] more...

Biological research on birds of the grouse family has become increasingly related to conservation. We review trends in grouse biology, analysing the representation of species and topics in the titles of 2,788 papers published since 1930. Ruffed grouse Bonasa umbellus, the most frequently studied species before 1960, was overtaken by willow ptarmigan Lagopus lagopus in the 1970s, after which black grouse Tetrao tetrix and capercaillie Tetrao urogallus became increasingly popular until they were the most-studied species in the 2000s. The new focus on conservation ecology involves increased interest in the topics of threatened taxa, genetics and conservation. Anew appreciation of the role of large, landscape-scale processes in population dynamics and conservation management is shown by an increase in publications on landscape ecology and habitat, enabled by technical advances in telemetry, genetics and mapping systems. Meanwhile, the number of papers on disease, diet, behaviour and reproduction has declined. The topics of climate change, human disturbance and pollution had few hits, but we anticipate that interest in them will increase as the current emphasis on conservation continues. This may well involve improved genetic and GIS techniques for determining dispersal patterns, habitat connectivity and population viability, along with a better understanding of how grouse survive their predators and other enemies. Better communication of experiences in management for grouse conservation is needed. [ABSTRACT FROM AUTHOR] more...

Abstract: This is the first article that describes in detail the bird remains from the Gravettian mega-site Pavlov I in the Czech Republic. More than 1000 bird bones represent at least 19 taxa, of which the most numerous are tetraonids including black grouse (Tetrao tetrix), willow grouse (Lagopus lagopus) and ptarmigan (Lagopus muta), and ravens (Corvus corax). The archaeological and biological contexts indicate that most birds were hunted by people in the vicinity of the site, possibly with the help of knotted nets made from plant fibres. We suggest that ravens were killed while feeding on carcasses and/or food remains that may have been disposed of intentionally, and feathers may have been used for arrow fletching. Human-modified bones indicate that birds were used not only for food but also as raw material for tools and decoration. Although mammals were certainly more important in the subsistence of the Gravettian people, it is clear that birds played a role in their culture. The location of Pavlov I enlarges the explanatory scope of the Broad Spectrum Revolution hypothesis to include higher latitudes north of the Mediterranean. [Copyright &y& Elsevier] more...

The article discusses the study relating to the sperm characteristics of a three-year-old male bird hybrid from a crossbreed of male Black Grouse and female Capercaillie through the dorso-abdominal massage technique. It explores the classification of nine morphological spermatozoa which includes normal, swollen, defective acrosome, bent neck, looped heads, defective midpiece, spermatids, dead cells and other deficiencies. The study assessed morphometry of the spermatozoa through histological smears by nigrosin-eosin complex. The result of the study reveals the equivalence of sperm concentration of the hybrid semen from both species. It also mentions the high percentage of abnormal morphology from the hybrid semen. more...

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Capercaillie (Tetrao urogallus L., 1758) and black grouse (Tetrao tetrix L., 1758 (= Lyrurus tetrix (L., 1758))) are two sympatric Eurasian lekking grouse species that differ markedly in habitat affinities and social organization. We examined how size and spacing of leks in pristine (Russia) and managed (Norway) forests were related to habitat and social behavior. Leks of both species were larger and spaced farther apart in the pristine landscape. Capercaillie leks were regularly spaced at 2-3 km distance, increasing with lek size, which in turn was positively related to the amount of middle-aged and older forests in the surrounding area. Black grouse leks were irregularly distributed at shorter distances of 1-2 km, with lek size explained by the size of the open bog arena and the amount of open habitat in the surroundings. At the landscape scale, spatial distribution of open bogs and social attraction among male black grouse caused leks to be more aggregated, whereas mutual avoidance in male capercaillie caused leks to be spaced out. In the pristine landscape, large-scale and long-term changes in forest dynamics owing to wildfires, combined with an aggregated pattern of huge bog complexes, presumably provide both grouse species with enough time and space to build up bigger lek populations than in the managed landscape. [ABSTRACT FROM AUTHOR] more...

The article focuses on a study that describes the development of a real-time polymerase chain reaction (PCR) assay to distinguish between faecal droppings from black grouse and two other tetraonid species that can occur sympatrically in Great Britain. The results from the assay were compared with those obtained using conventional hot-start, end point PCR followed by sequencing. Both in terms of the number of identifications made and concomitantly, the sequencing approach proved to be more successful than that of real-time PCR. more...

The article focuses on a study which examined the spatial and temporal patterns of artificial nest predation in mountain birch forests fragmented by spruce plantations. The study area was in the municipalities of Skånland and Evenes in Nordland and Troms counties in northern Norway. Ground-breeding birds found in the area included ducks, waders, black grouse, willow grouse and passerines. Mammalian nest predators include the red fox and pine marten. Results show that eggs were preyed upon by eight different predators. It indicates the potential for bird predation to increase in the next 3 years. more...

The article presents the paper "Black Grouse Response to Dedicated Conservation Management" from the Fourth International Black Grouse Conference in Vienna, Austria, in September 2007. This paper examines the results of initiatives that employ various management strategies to improve habitat conditions and reduce direct sources of mortality to black grouse in Great Britain. It observes a frequent lack of control sites and baseline data concerning the initiatives. It notes variation in annual productivity that appeared to be a major determinant of black grouse population trends. more...

The article discusses the paper "Preliminary Results From a Translocation Trial to Stimulate Black Grouse Tetrao tetrix Range Expansion in Northern England" presented at the Fourth International Black Grouse Conference in Vienna, Austria, in September 2007. This paper examined a translocation trial to expand the range of black grouse into suitable habitats on the fringe of their range. It selected two release sites which were considered to have suitable habitat to sustain a lekking group. It observed lekking among dispersed black grouse. more...

The article discusses the paper "Mitigating Against the Impacts of Human Disturbance on Black Grouse Tetrao Tetrix in Northern England" presented at the Fourth International Black Grouse Conference in Vienna, Austria, in September 2007. This paper investigated the impact of increased human recreational disturbance on black grouse in northern England. It examined the condition of black grouse during the winter at residual patches of heather moorland. It showed the susceptibility of black grouse to increased recreational disturbance at winter feeding areas. more...

The article discusses the paper "Patterns of Black Grouse, Tetrao Tetrix Distribution in Northwestern Russia at the Turn of the Millennium" presented at the Fourth International Black Grouse Conference in Vienna, Austria, in September 2007. To understand the declining populations of black grouse in Finland and Russia, the paper examined the relationship between landscape structure and black grouse density in Russian Karelia and compared it with East Finland. It showed low correlations between forest structure and black grouse abundance. more...

The article discusses the paper "Distribution and Number of Black Grouse, Tetrao Tetrix in Southwestern Poland and the Potential Impact of Predators Upon Nesting Success of the Species" presented at the Fourth International Black Grouse Conference in Vienna, Austria, in September 2007. This paper investigates the distribution and number of black grouse in coniferous lowland forest. It discusses the application of time-space analysis in the investigation. It shows increasing black grouse population in eight hunting districts within a forest area. more...

The article discusses the paper "New Methods for Preservation of Genetic Diversity of Black Grouse, Tetrao Tetrix: Preliminary Results" presented at the Fourth International Black Grouse Conference in Vienna, Austria, in September 2007. This paper provides an approach to the problem of conserving the small and endangered populations of black grouse. It elaborates field non-invasive methods that enables to obtain the genetic material without removing birds from natal populations. It considers a method of mating hen from the aviary with wild cock. more...

The article discusses the paper "Genetic Studies of Black Grouse With Special Reference to Conservation Biology: A Review" presented at the Fourth International Black Grouse Conference in Vienna, Austria, in September 2007. This paper reviews genetic studies of black grouse to date. It covers different areas such as reproductive biology, mating system and conservation genetics. The paper shows that black grouse populations are genetically differentiated in the western part of the range of the species. more...

The article discusses the paper "Impact of Wind Power Plants on Black Grouse, Lyrurus Tetrix in Alpine Regions" presented at the Fourth International Black Grouse Conference in Vienna, Austria, in September 2007. This paper correlates a strong decline in the population of black grouse in Styria, Austria, with wind power plants. It highlights collisions of the birds with the towers and disturbance because of wind park maintenance as among the impact of wind power plants on black grouse. It also notes the overlapping of locations for windpower plants in alpine regions with lek sites of black grouse. more...

This publication offers information about the status of birds found in Great Britain, Channel Islands and Isle of Man. Birds covered in this issue are categorized into three lists, Red, Amber and Green, which are based on objective criteria. Some of the factors considered by the listings are global conservation status, historical population decline and international importance of populations. Bird species included in the lists are Black grouse, White-tailed Eagle, Common Cuckoo and Yellow Wagtail. more...

The declines of many specialist bird species in the agricultural landscapes of Central Europe have resulted in small and isolated populations. In the case of the black grouse, a ground-nesting bird species with large spatial requirements, empiric evidence about underlying landscape changes is scarce. In this study, we examined land cover and land cover changes in a farmland-forest mosaic in eastern Lower Saxony, Germany and how they affect occurrence and persistence of black grouse. Spatial information came from historic topographic maps from 1958 to 1975. The results show profound conversions of habitat to forest and farmland but also an increase in settlement area. Habitat conversions and suburbanization were negative correlates of black grouse persistence. Habitat models from before and after a decline period differed in some of the predictors and suggest black grouse habitat to be more diverse before the land cover changes. Our study confirms that land use factors at a landscape scale extent contribute to explain black grouse occurrence and thus can complement important small scale factors like the quality and size of individual habitat patches. Results also show that landscape factors affect black grouse distribution predominantly from an area much greater than an individual black grouse home range. Our models may be further evaluated on present-day landscapes and might be used to evaluate large-scale habitat availability for black grouse. [ABSTRACT FROM AUTHOR] more...

1. Tourism and leisure activities have increased continuously all over the world during the past decades, exerting a growing pressure upon naturally fragile ecosystems, such as mountainous habitats. Recent studies have established that disturbance by outdoor winter sports (e.g. skiing, snowboarding and snowshoeing) is a source of stress for wildlife. This may in turn affect its abundance, but we still lack quantitative evidence. 2. We tested the effect of outdoor winter sports (ski lifts and related recreational activities) on the abundance of the alpine black grouse Tetrao tetrix, a vulnerable indicator species of the timberline ecosystem, the favoured habitat for outdoor winter sports in the European Alps. 3. Generalized linear models and a model selection approach were used to rank environmental factors influencing black grouse abundance and to make predictions about population status in the theoretical absence of ski resorts. We modelled the number of displaying cocks along census transects in spring, as a function of habitat characteristics (vegetation structure and typology), ski lift density and hunting pressure at 15 natural sites (none or a very low level of anthropogenic disturbance) and 15 ski resorts in the south-western Swiss Alps. 4. Ski lift density and habitat typology were the principal determinants of black grouse abundance, whereas hunting pressure had no discernable effect. Ski lifts and related winter sport activities had a strong negative effect on the number of displaying cocks, which may have led to a mean 36% reduction of local abundance in ski lift areas, as determined after controlling for the confounding effect of habitat type. 5. Synthesis and applications. Conservation action plans for black grouse should aim at reducing the multiple negative effects generated by outdoor winter sports (ski facilities and related winter sport activities). First, vegetation patchiness (i.e. a mosaic of grassy shrubland with scattered trees) should be maintained along ski runs. Secondly, wintering preserves where human access is banned or strictly limited should be promoted within ski resorts. Spatially explicit human–wildlife conflict maps can be constructed from the present model to allow delineation of those areas likely to become effective protection areas. [ABSTRACT FROM AUTHOR] more...

In lekking species, males cluster on specific areas for display (the leks) and females generally prefer to copulate with males on large aggregations. The maintenance of leks in which only a few males reproduce might be explained if subordinate males gain indirect fitness benefits. By joining a lek on which relatives are displaying, subordinates might attract more females to the lek thereby increasing the mating opportunities of their kin. In black grouse, a genetic structure among leks has previously been found suggesting that relatives could display together. Using 11 microsatellite loci, we extended this result by testing for the presence of kin structures in nine black grouse leks (101 males). The genetic differentiation among flocks was higher in males than in females, suggesting female-biased dispersal and male philopatry. Because of this genetic structure, males were more related within than among leks. However, the mean relatedness within each lek hardly differed from zero. The lekking males were not more related than random assortments of males from the winter flocks and there were no kin clusters within leks. Thus, black grouse males do not choose to display with and close to relatives. Male philopatry alone was not sufficient to induce elevated levels of relatedness on the leks either because of male partial dispersal or a rapid turnover of the successful males. The indirect fitness benefits associated with males’ settlement decision are probably limited compared to the direct benefits of joining large aggregations such as increased current and future mating opportunities. [ABSTRACT FROM AUTHOR] more...

We have studied a small isolated population of black grouse ( Tetrao tetrix) in the Netherlands to examine the impact of isolation and reduction in numbers on genetic diversity. We compared the genetic diversity in the last extant Dutch population with Dutch museum samples and three other black grouse populations (from England, Austria and Norway, respectively) representing isolated and continuous populations. We found significantly lower allelic richness, observed and expected heterozygosities in the present Dutch population compared to the continuous populations (Austria and Norway) and also to the historical Dutch population. However, using a bottleneck test on each population, signs of heterozygosity excess were only found in the likewise isolated English population despite that strong genetic drift was evident in the present Dutch population in comparison to the reference populations, as assessed both in pairwise FST andstructure analyses. Simulating the effect of a population reduction on the Dutch population from 1948 onwards, using census data and with the Dutch museum samples as a model for the genetic diversity in the initial population, revealed that the loss in number of alleles and observed heterozygosity was according to genetic drift expectations and within the standard error range of the present Dutch population. Thus, the effect of the strong decline in the number of grouse on genetic diversity was only detectable when using a reference from the past. The lack of evidence for a population reduction in the present Dutch population by using the programbottleneck was attributed to a rapidly found new equilibrium as a consequence of a very small effective population size. [ABSTRACT FROM AUTHOR] more...

1. The breeding success of Finnish grouse has been in decline for decades. While it has been shown that fragmentation and modern forestry practices such as clear-cutting affect the viability of grouse populations, little is known about effects of large-scale drainage. The drainage network in Finland has increased dramatically during the past decades. By 1988, 6 million ha of bog ecosystems had been drained. This is likely to have had a profound direct and indirect effects on grouse productivity. Because ditches persist in time, large-scale drainage may therefore have strong potential for affecting the long-term breeding success of three forest grouse species in Finland. 2. Using a mixed-model approach on nation-wide data, we estimate the effects of drainage on breeding success of three grouse species for the period from 1966 to 1988. The possible additive effect of precipitation is investigated using regional precipitation data. For each species, we compare a set of hypotheses and select the best model(s) according to the Akaike information criterion. 3. For all species, the model which included the main effects of both ditch density and precipitation outperformed the models with just one of the main effects as well as the interaction model. The effects are restricted to southern and central Finland, where drainage is most intensive. 4. The effects of drainage are likely to be both direct and indirect, but the mechanisms are less clear. Both bottom-up, such as decreased availability of insect food, and top-down effects, such as increased predation risk, may account for indirect effects. Direct effects are likely to involve drowning of chicks. 5. Synthesis and applications. Bogs are classified as key biotopes by the European Union, and Finland is obliged to maintain their favourable conservation status and to protect typical bog communities. While this goal may be achieved for state-owned land, restoration of drainage systems on private land continues. Considering the persistence of ditches, new legislation are therefore needed to favour the recovery of former bogs and mires on private land as well as to protect remaining ones. [ABSTRACT FROM AUTHOR] more...

In bird species with pair bonds, extra-pair matings could allow females to choose genetically superior males. This is not needed in lekking species because female choice is not constrained by pairing opportunities. However, polyandry has been reported in most lekking species studied so far. Using 12 microsatellite loci, we determined the paternity of 135 broods of black grouse sampled between 2001 and 2005 (970 hatchlings and 811 adult birds genotyped). The paternity assignments were combined to lek observations to investigate the mating behaviour of black grouse females. About 10% of the matings seemed to take place with males displaying solitarily. Forty per cent of the copulations between males displaying on the studied leks and radio-tagged females were not recorded. This was due to difficulties in identifying the females and because our observations did not cover all the possible time for matings. However, females of the undetected copulations had chosen males that were already known to be successful on the leks. There was a strong consistency between the observations and true paternity, even when the copulation was disturbed by a neighbouring male. Multiple mating and multiple paternities were rare. We can now confidently ascertain that most females mate only once with one male for the whole clutch. This mating behaviour requires that a single insemination is sufficient to fertilize a clutch and that females can determine whether the sperm has been successfully transferred. Grouse Tetraoninae with many lekking species may be the only bird taxon that has evolved these traits. [ABSTRACT FROM AUTHOR] more...

We found that the Black grouse ( Tetrao tetrix) possess low numbers of Mhc class II B ( BLB) and Y ( YLB) genes with variable diversity and expression. We have therefore shown, for the first time, that another bird species (in this case, a wild lek-breeding galliform) shares several features of the simple Mhc of the domestic chicken ( Gallus gallus). The Black grouse BLB genes showed the same level of polymorphism that has been reported in chicken, and we also found indications of balancing selection in the peptide-binding regions. The YLB genes were less variable than the BLB genes, also in accordance with earlier studies in chicken, although their functional significance still remains obscure. We hypothesize that the YLB genes could have been under purifying selection, just as the mammal Mhc- E gene cluster. [ABSTRACT FROM AUTHOR] more...

Capercaillie (Tetrao urogallus) broods prefer habitats that contain food for the chicks and cover against predators. During the summer 2005, in each of nine areas, three initially similar forest stands were examined: one was harvested by clear-cutting and one by selective cutting, while the last was uncut. Brood habitats in terms of food availability and cover from predators in old forest stands were compared with those in selectively cut and clear-cut stands. The selectively cut forest stands were more open, so the chicks may have been easier to detect by raptors. On the clear-cuts the preferred chick food, Lepidoptera larvae, was less abundant and the measurements suggest that the chicks were easier to detect. If the amount of available brood habitat positively influences chick survival, clear-cutting is likely to decrease chick survival. Selective cutting preserves food availability, but may increase predation by raptors. [ABSTRACT FROM AUTHOR] more...

The Western capercaillie (Tetrao urogallus) is a keystone species of Palearctic boreal and altitude coniferous forests. With the increase of mountain leisure activities and habitat loss, populations are declining in most mountain ranges in Western Europe. Recent work has shown that the populations from the Pyrenees and Cantabrian Mountains survived a severe bottleneck during the 19th century, and are still considered as threatened due to habitat fragmentation and isolation with other populations. We present an extensive phylogeographic study based on mitochondrial DNA sequence (control region) extracted non-invasively from faeces collected throughout the species range (from western European mountains to central and eastern Europe, Fenno-Scandia, Russia and Siberia). We also compared our results with DNA sequences of closely related black-billed capercaillie (T. parvirostris). We found that populations from Pyrenees and Cantabrians are closely related but are different from all other capercaillie populations that form a homogenous clade. Therefore, we consider that these South-Western populations should be considered as forming an Evolutionary Significant Unit that needs an appropriate management at a local scale. We also discuss the possible locations of glacial refugia and subsequent colonisation routes in Eurasia, with a Western ‘aquitanus’ lineage from Iberia and Balkans, and an Eastern ‘urogallus’ lineage from Southern Asia. This work might have important implication for capercaillie conservation strategies to define important areas for conservation, and to prevent possible exchange or introductions of individuals originated from other lineages. [ABSTRACT FROM AUTHOR] more...

We studied microsatellite genetic variation in 14 different geographic populations of black grouse (Tetrao tetrix) across the European range. Populations were grouped in three different fragmentation categories: isolated, contiguous and continuous, respectively. Genetic diversity, measured as observed heterozygosity (HO), expected heterozygosity (HE) and allelic richness, were lower in isolated populations as compared to the other two categories that did not differ amongst one another. These results imply that lowered genetic variability in black grouse populations is negatively affected by population isolation. Our results suggest that the connectivity of small and isolated populations in Western Europe should be improved or else these face an increased risk of extinction due to genetic and demographic stochasticity. [ABSTRACT FROM AUTHOR] more...

Recent progress in techniques of quantifying between-individual differences of color-based ornaments has revealed undiscovered possibilities for research in sexual selection. We present how the color spectra data can be comprehensively used for studying the importance of sexual ornaments in the black grouse and how these ornaments are related to a male condition. For this, we used both correlative field and experimental data. Field data indicated that older males had more chromatic coloration than yearlings. Blue chroma of males was correlated with male mating success. We experimentally manipulated yearling birds with testosterone implants and found that testosterone-implanted males had impaired expression of several sexual ornaments: 10 months after the implantation, both structural-based blue and carotenoid-based red eye comb coloration were diminished, as well as lyre (tail) length. However, the manipulation did not affect vital traits under natural selection (wing length or body mass). Our data indicate that structural color is an important trait in sexual selection in this lekking species. Importantly, the data also indicate that male sexual ornaments are more susceptible to environmental conditions than the other male traits, thus showing their heightened condition dependency compared with the other traits mediating the honesty of signaling. [ABSTRACT FROM AUTHOR] more...

In the United Kingdom, Black Grouse Tetrao tetrix have declined in range and abundance during the 20th century. In England at present, birds are largely found only on the margins of managed grouse moors in the north, where more than 80% of birds are confined to the North Pennines Area of Outstanding Natural Beauty. The Black Grouse is one of a group of species potentially at risk from increased human recreational disturbance owing to their threatened status and their use of habitats to which a statutory right of human recreational access has recently been granted. To assess the likely impact of increased disturbance to Black Grouse, 77 were caught and radiotagged between 2002 and 2004, and each was randomly assigned to one of three experimental disturbance categories: no disturbance (low), fortnightly disturbance (moderate) or twice weekly disturbance (high). Birds that were disturbed more regularly flushed at greater distances, especially in spring and winter when birds exposed to high disturbance flushed at 32% greater distances than those in moderate disturbance treatments. There were no differences in fecundity (clutch size, hatching success, breeding success) or survival between disturbance treatments. Winter survival was 78% and summer survival 92%. There was no age-related difference in survival. The disturbance regimes imposed had no discernible impact upon Black Grouse population dynamics. However, in the absence of appropriate data to indicate likely changes in patterns and levels of human recreation resulting from open access, we cannot be sure whether the levels we applied will be representative in the future. Should actual disturbance levels be higher than those we used in this study, we list visitor management options that may help reduce any conflict that arises. [ABSTRACT FROM AUTHOR] more...

Black Grouse Tetrao tetrix in Britain have declined through the 20th century, and most birds are now in Scotland. Many causes for this decline have been suggested, notably agricultural intensification, increased grazing levels and moorland afforestation. We examine habitat correlates of Black Grouse distribution and population change from a 700-km2 area in the core of the Scottish range, where the numbers of lekking male Black Grouse declined by an estimated 70% to 270 between 1990 and 2002. Habitat data were derived from satellite imagery, in combination with map and field-collected data. Lek occurrence, lek size and changes in lek size were all correlated with forest structure, either positively with the amount of pre-thicket forest cover, or negatively with closed canopy cover. Additional effects of the cover of grass moor and dry heath suggest that Black Grouse are most likely to occur where moorland comprises Heather Calluna vulgaris and grass mosaics. Analysis of the change in Black Grouse abundance within 1.5 km of discrete forest blocks suggests that forest maturation, which has been the dominant habitat change during the course of the study, alone accounts for 58–78% of the decline. Given the close association of Black Grouse and the occurrence of woodland (and particularly conifer plantation) throughout much of their British range, these findings can be used to inform the design of management schemes for the recovery of Black Grouse. [ABSTRACT FROM AUTHOR] more...

Parasite infections are often more common in male vertebrates than in females. Sexual selection leading to dimorphism can cause sexual differences in immune defence, behaviour or body size. Possible proximate explanations for male bias in parasitism are the immunosuppressive effect of male sex hormones and the large body size of males which increases the likelihood of being parasitized. To evaluate these hypotheses, we studied the prevalence and abundance of intestinal helminth parasites in three boreal grouse species, the capercaillie Tetrao urogallus, the black grouse Tetrao tetrix, and the hazel grouse Bonasa bonasia. The first two are sexually dimorphic polygynous species while the latter species is sexually monomorphic and monogamous. We found a male-bias in the prevalence and abundance of the nematode Ascaridia compar. The bias was most pronounced in the polygynous black grouse and capercaillie. In the monogamous hazel grouse, there was a slight male-bias in occurrence of ascarids, but no bias in abundance. In juvenile grouse, the male-bias was larger than in adult grouse. No sexual bias was found in regard to the cestodes ( Skrjabinia cesticillus, Paroniella urogalli and Hymenolepis spp.). However, age was a factor in cestode prevalence: juvenile grouse were more commonly infected than adults. Differences in growth rates and body size are potential factors that may lead to male-biased parasitism in these grouse species, and their impact requires further studies. [ABSTRACT FROM AUTHOR] more...

Temporal asymmetry in patterns of regional climate change may jeopardize the match between the proximate and ultimate cues of the timing of breeding. The consequences on short- and long-term population dynamics and trends as well as the underlying mechanisms are, however, often unknown. Using long-term data from Finland, we demonstrate that black grouse (Tetrao tetrix) have responded to spring warming by advancing both egg-laying and hatching. However, early summer (the time of hatching) has not advanced, and chicks have to face colder post-hatching conditions. Demonstrating that these conditions are critical to post-hatching survival, we show that chicks are increasingly suffering higher mortality because they hatch too early. Consequently, breeding success and population size has severely declined over the past four decades. Finally, we modelled the impact of this particular climate change scenario on population dynamics and show that the mismatch can further explain the observed collapse of cyclic fluctuations. Because the evolutionary response of grouse is lagging behind the novel selective pressures, seasonally asymmetric climate change is likely to constitute an important determinant of future short- and long-term changes in the dynamics of black grouse populations. [ABSTRACT FROM AUTHOR] more...