Variation in Egg Dimensions in a Hooded Crow
نویسندگان
چکیده
Variation in egg size and shape of the Hooded Crow Corvus corone cornix was investigated in the National Park Ujcie Warty, western Poland, in 2000 and 2001. Mean clutch size was 4.55±0.79 (n=40). Coefficients of variation for clutch means ranged from 2.00±1.16 (breadth) to 3.35±1.76 (elongation index). Mean repeatability estimates were 0.69, 0.71, 0.73, and 0.62 for length, breadth, volume, and elongation index, respectively. The results suggest that in the population studied, one should expect a relatively high heritability of egg dimensions and thereby a low influence of environmental conditions. This can be connected with the food storage ability in corvids.
منابع مشابه
Un-paint it black: Avian prey as a component of the diet of nestling Hooded Crows Corvus cornix
The Hooded Crow (Corvus cornix) is often considered the main nest predator of many bird species, especially waterbirds. Such relationship should be particularly clear during the breeding season in wetlands, when the need to supply their nestlings with the highest quality foods forces predators to intensify their hunting activities. Hence, waterbirds should be their basic prey. We examined the c...
متن کاملIgnorant hooded crows follow knowledgeable roost-mates to food: support for the information centre hypothesis.
Communal roosting in birds may function to enhance foraging efficiency as explained by the information centre hypothesis, which predicts that successful foragers return from the roost to the rewarding food patch and that birds ignorant of this food follow knowledgeable roost-mates. We tested these predictions by exposing 34 radio-tagged, free-ranging, flock-living hooded crows (Corvus corone co...
متن کاملThe Genetics of Speciation and Colouration in Carrion and Hooded Crows
Poelstra, J. 2013. The Genetics of Speciation and Colouration in Carrion and Hooded Crows. Acta Universitatis Upsaliensis. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1088. 48 pp. Uppsala. ISBN 978-91-554-8777-5. A fundamental goal in biological research is to gain an understanding of the evolutionary processes and genetic elements that dr...
متن کامل[Karyological study of some Corvine birds (Corvidae, aves)].
Karyotypes were studied in the hooded and carrion crows, their naturally occurred hybrids, the jungle crow, the azure-winged magpie (2n = 80 in all aforementioned birds), and the magpie (2n = 82). Corvine birds of Primorskii Krai were karyotyped for the first time. In addition to the similarity in the diploid chromosome sets, corvine birds were shown to have a similar structure of karyotype: in...
متن کاملCLUTCH SIZE, EGG DIMENSIONS AND BREEDING STRATEGY IN THE NUTHATCH Sitta europaea Veličina pologa, dimenzije jaja i strategija gniježđenja brgljeza Sitta europaea
This study presents clutch size, egg-characteristics and within-clutch egg dimensions variation in Nuthatch Sitta europaea in deciduous forests (Hrvatsko zagorje area; NW Croatia). Study comprised the period from 2000 to 2002. Cluch size were 5–8 eggs (mean = 6.63, modal = 7 eggs). Egg length averaged 19,79 mm, egg breadth 14.42 mm, egg volume 2099.66 mm3 and egg shape index 1,37 (during tree y...
متن کامل