Tag: all of Pyrrhocorax

Identifying the demographic determinants of population growth rate: a case study of red-billed choughs Pyrrhocorax pyrrhocorax

Chough (Pyrrhocorax pyrrhocorax) Science Article 3 abstract Identifying which age-specific demographic rates underlie variation in a population’s growth rate (?) is an important step towards understanding the population’s dynamics. Using data from a 20-year study of marked individuals, we describe patterns of demographic variation and covariation in the Scottish red-billed chough population (Pyrrhocorax pyrrhocorax), and […]

Breeding density and distribution of Choughs Pyrrhocorax pyrrhocorax nesting in river cliffs: The role of nest-site availability.

Chough (Pyrrhocorax pyrrhocorax) Science Article 2 abstract The breeding abundance of Choughs Pyrrhocorax pyrrhocorax was investigated in relation to type of rock and related features of nesting cliffs along rivers in south-eastern Madrid (Central Spain). Gypsum cliffs are larger and provide more nest sites than clay and limestone cliffs. Cliffs used by breeding Choughs contained […]

Age-specific reproductive performance in red-billed choughs Pyrrhocorax pyrrhocorax: patterns and processes in a natural population

Chough (Pyrrhocorax pyrrhocorax) Science Article 5 abstract Using data from a 20-year study of individually marked red-billed choughs, we examine how reproductive performance varies with age in male and female breeders, and investigate whether population-level trends result from changes in individual performance and/or the phenotypic composition of the breeding population. Across the population, mean clutch […]

Environmental variability, life-history covariation and cohort effects in the red-billed chough Pyrrhocorax pyrrhocorax

Chough (Pyrrhocorax pyrrhocorax) Science Article 4 abstract The consequences of environmental variability for life-history evolution are predicted to depend on the pattern of covariation amongst life-history traits. Using data from a 20-year study of individually marked red-billed choughs, we investigate the short- and long-term life-history consequences of population-wide variation in reproductive conditions, and demonstrate clear […]

Demographic consequences of prey availabilityand diet of Red-billed Choughs Pyrrhocoraxpyrrhocorax

Chough (Pyrrhocorax pyrrhocorax) Science Article 6 abstract Capsule Variation in prey availability appears to influence Chough fledging success and juvenile survival. Aims To determine seasonal and annual variations in Chough prey and how these influence fledging success and juvenile survival. CHRISTIAN KERBIRIOU and ROMAIN JULLIARD, Bird Study (2007) 54, 296-306 Download article download full text […]

Geographic diversification in the call repertoire ofthe genus Pyrrhocorax (Aves, Corvidae)

Alpine Chough (Pyrrhocorax graculus) Science Article 2 abstract We analysed the call repertoires of the Red-billed Chough (Pyrrhocorax pyrrhocorax) and the AlpineChough (Pyrrhocorax graculus) across three continents (Europe, Asia, and Africa) for intraspecific and interspecificdifferences in call-repertoire size and discuss the factors that could have promoted its evolution. Paola Laiolo, Antonio Rolando, Anne Delestrade, and […]

WINTER MOVEMENTS OF THE ALPINE CHOUGH: IMPLICATIONS FOR MANAGEMENT IN THE ALPS

Alpine Chough (Pyrrhocorax graculus) Science Article 1 abstract The home ranges and movements of marked Alpine choughs (Pyrrhocorax graculus) were investigated in Aosta Valley, western Italian Alps, in two study sessions: winter-spring 1996-1997 and winter-spring 1997-1998. Overall 28 birds were marked, six of these were also equipped with a small radio tag. P. Laiolo, A. […]

Sexual Size Dimorphism and Positive Assortative Mating in Alpine Choughs (Pyrrhocorax graculus)

Alpine Chough (Pyrrhocorax graculus) Science Article 3 abstract The degree of sexual size dimorphism in a number of different morphological characters was examined in a social corvid, the Alpine Chough, using measurements taken on 178 males and 144 females ANNE DELESTRADE, The Auk 118(2):553-556, 2001 Download article download full text (pdf)

Age and sex determination of monomorphic non-breeding choughs: a long-term study

Chough (Pyrrhocorax pyrrhocorax) Science Article 1 abstract We present criteria for sexing and aging non-breeding Choughs( Pyrrhocorax py rrhocorax) based on nine years of capture-recapture data. Shape of the rectrices, intensity of plumage colour and iridescent brightness , and the contrast between old flight feathers and freshly molted ones allowed us to distinguish three age […]

Age and sex determination of monomorphic non-breeding choughs: a long-term study

Chough (Pyrrhocorax pyrrhocorax) Science Article 1 abstract We present criteria for sexing and aging non-breeding Choughs( Pyrrhocorax py rrhocorax) based on nine years of capture-recapture data. Shape of the rectrices, intensity of plumage colour and iridescent brightness , and the contrast between old flight feathers and freshly molted ones allowed us to distinguish three age […]