Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 53

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 3 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 3 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Birds may occasionally breed far beyond the average breeding time for particular species. Nesting attempts in winter during unfavorable weather and unfavorable environmental conditions, however, are particularly rare events. In this note I report an unsuccessful attempt of a Blackbird Turdus merula L. observed in January, 2009 in SW Poland. The clutch was abandoned at the final stage of incubation. Unlike other reported cases, it had been started on the outskirts of an average-sized town, in a period of harsh weather– low ambient temperature and snow cover present. This is the first winter brood of this species recorded in Poland and probably the easternmost in Europe. It is suggested that winter breeding by Blackbirds may occur more regularly and in wider areas than previously reported.
During seven winter seasons (1993/1994-1999/2000) 107 roadside counts (28 km each) in agricultural area of south-western Poland were conducted. From among 1526 Buzzards, 1293 were recorded in winter months (November-February) and 233 in March. Birds were non-randomly distributed on nine vegetation types met along the transect route. Permanent papilionaceous crops, along with cereal stubbles, margin habitats, meadows and maize stubbles were preferentially used, whereas bare tillage and winter cereals were avoided. In general, Buzzards preferred habitats of the least amount in the studied area and avoided those which dominated. These data support the idea of high importance of small landscape structures for the biodiversity protection in intensively used farmland. During winter months, most Buzzards (59.5%) were perched when first sighted, most often on trees and in the middle part of their height. The percent of birds sitting on the ground amounted to 34.7%. The smallest amount of individuals (5.8%) was observed flying (flap-sailing, hovering and soaring), however this activity significantly increased in March (up to 17.1%). The significance of various hunting methods for wintering Buzzards is discussed. Even though it is a typical perch hunting raptor, the method of hunting from the ground seems to be particularly suitable for the conditions of winter farmland: common scarcity of perches, poor and low vegetation, local and temporary prey concentrations.
It is widely accepted that the first White Storks to arrive at a nest remain there to breed. In contrast to this belief, the paper describes the replacement of at least three males and at least one female at one nest in SW Poland during the spring of 1994. The first pair occupied the nest for 5-8 days, the second pair for one day, and probably only the third pair remained at the nest to actually breed. Additional data on arrival patterns show that such replacements of non-breeding storks may occur much more frequently than was previously thought, especially in areas of intense migration. Consequently, the most common phenological observations (e.g. the arrival dates of the first and second White Storks) are not really useful for defining the timing of breeding. It is suggested that the beginning of nest occupancy should be defined by the beginning of the permanent stay of the second partner, and not just by the date of the birds' first appearance.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 3 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.