Caspian Tern (Sterna caspia) Science Article 3 abstract We examined spatial and temporal foraging patterns of Caspian terns and double-crested cormorants nesting in the ColumbiaRiver estuary, to potentially identify circumstances where juvenile salmonids listed under the U.S. Endangered Species Act mightbe more vulnerable to predation by these avian piscivores. Data were collected during the 1998 […]
Habitat selection of Hooded and Carrion Crows in the alpine hybrid zone
Carrion Crow (Corvus corone corone) Science Article 3 abstract Habitat selection of co-existing Hooded Crows Corvus corone cornix and Carrion Crows C. c. corone was studied in the Susa valley, an alpine valley in the Iitalian hybrid zone. Foraging habitat use by the two races was not significantly different during the autumn-winter whereas it was […]
Does year-round territoriality rather than habitat saturation explain delayed natal dispersal and cooperative breeding in the carrion crow?
Carrion Crow (Corvus corone corone) Science Article 4 abstract The ecological factors that promote delayed dispersal of offspring in cooperatively breeding bird species are poorly understood. While single population studies have supported the view that natal dispersal is delayed as a consequence of lack of suitable breeding vacancies (ecological constraints hypothesis), recent theoretical models claim […]
Kleptoparasitism by Peregrine Falcons on Carrion Crows
Carrion Crow (Corvus corone corone) Science Article 1 abstract […]. The study area was Bizkaia, a small province of 2300 km2 located in the north of Spain. In this area we have monitored about 35-38 Peregrine territories since 1997. During this time we have studied the prey of Peregrines in the nests, recording 931 prey […]
Reproductive success increases with group size in cooperativecarrion crows, Corvus corone corone
Carrion Crow (Corvus corone corone) Science Article 5 abstract The effect of group size and the number of helpers on reproductive success is crucial to understand theevolution and maintenance of cooperative breeding. In northern Spain, carrion crows form kin-groups(three to nine individuals) where up to five individuals contribute to rearing the young DANIELA CANESTRARI et […]
Pair composition and reproductive success across a hybrid zone of carrion crows and hooded crows
Carrion Crow (Corvus corone corone) Science Article 2 abstract The Carrion Crow (Corvus corone corone) and the Hooded Crow (C. corone cornix) have parapatric ranges in Europe with narrow areas of hybridization. Reproductive biology of populations of Carrion and Hooded crows and hybrids is described for four areas in northern Italy. Nonrandom mating was observed […]
BEHAVIOR OF WHISTLING AND CAPPED HERONS IN THE SEASONAL SAVANNAS OF VENEZUELA AND ARGENTINA
Capped Heron (Pilherodius pileatus) Science Article 1 abstract Behavior, habitat use, and foraging of the Whistling Heron (Syrigma sibilatrix)a nd Capped Heron (Pilherodiusp ileatus)w ere studied in Venezuela and Argentina. Both foraged primarily alone or in pairs, but Whistling Herons also fed and roosted socially. Whistling Herons nested solitarily, maintained post-fledging associations with young, and […]
Habitat features of the capercaillie (Tetrao urogallus) leks in the West Carpathians
Capercaillie (Tetrao urogallus) Science Article 4 abstract Habitat characteristics of 43 capercaillie (Tetrao urogallus) leks were studied in the mountains of Central Slovakia (West Carpathians) in 1984-2002. Macro-habitat was described with respect to topography and succession stage. Micro-habitat was described with respect to forest type and forest stand structure. Twenty-seven out of forty-three display grounds […]
Phylogeography of the European capercaillie (Tetrao urogallus ) and its implications for conservation
Capercaillie (Tetrao urogallus) Science Article 11 abstract The phylogeographic pattern of mitochondrial DNA variation in capercaillie (Tetrao urogallus) from 14 populations across the European range was examined using sequence variation in the central portion of the control region and the cytochrome B gene. Twenty-nine different haplotypes were resolved, which formed two distinct phylogenetic clades. The […]
Spacing of adult and subadult male Common Capercaillie during the breeding season
Capercaillie (Tetrao urogallus) Science Article 2 abstract The spacing behavior of 58 male Common Capercaillie (Tetrao urogaIlus) was studied at Varaldskogen in southeast Norway during 1979-1985. Birds captured at leks were equipped with radio-transmitters, and their movements were monitored throughout the year. During spring, males 4 yr old and older occupied exclusive day territories of […]