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Analysis of mallard’s (Anas platyrhynchos) behavior depending on phenology period and the size of the flock on water basins in Szczecin

100%

Wojcieszak H., Wysocki D., Kaliciuk J.

Zeszyty Naukowe. Acta Biologica. Uniwersytet Szczeciński

2013

tom 20

The subject of the study is the behaviour of Mallard’s Anas platyrhynchos and was carried out in the city of Szczecin (Poland) in 2009–2010. We compared frequency of fights, rapes, courtships, copulations and whistles on a water basins within both big and small flocks, and in different phenology periods. The study shows significant relationship between season, number of ducks on a pond and frequency of fights, as well as between whistles and fights, whistles and season and courtships and season. The results show that the most active period for ducks are the autumn and winter months (pairing period), while more aggressive behaviours can be observed when the population density is high.

Relative abundance and flock size of wintering Common Crossbills Loxia curvirostra L. in Western Carpathians: a habitat influence

80%

Ciach M., Bylicka M.

Polish Journal of Ecology

2009

tom 57

nr 1

181-189

A study of wintering Common Crossbills (Loxia curvirostra L.) was conducted in the winter periods 2002/2003–2006/2007 in the Western Carpathians. Birds were surveyed on transects in natural mountain European beech (Fagus sylvatica L.)-Silver fir (Abies alba Mill.)- Norway spruce (Picea abies (L.) Karst.) forests of the Tatra Mts, Pieniny Mts, Babia Góra Mt. and Gorce Mts (total length 41.4 km) as well as in a habitat mosaic with Scots pine (Pinus sylvestris L.) and Mountain pine (Pinus mugo Mill.) stands in the Kotlina Orawsko-Nowotarska valley (total length 31.5 km). Birds mean density underwent annual changes from 1.9 to 15.5 ind. 10 km⁻¹ in the natural mountain forests and from 0.9 to 12.1 ind. 10 km⁻¹ in the habitat mosaic. The median flock size in the natural mountain forests was 2, and it varied from 1 to 4 in subsequent seasons. They were smaller than flocks recorded in the habitat mosaic in the valley – median 2.5 (from 2 to 7 in subsequent seasons). The size of foraging and flying flocks did not differ significantly in natural mountain forest nor in the valley habitat mosaic. In the natural mountain forests, birds preferred habitats dominated by Norway spruce, and avoided European beech-Silver fir forests. The median flock size was 2 in habitats with Norway spruce, and 8 in stands where Norway spruce was absent. The variation in bird density presumably reflected the changes in quantity and location of food resources. Birds moved within stands with varying proportions of Norway spruce in the mountains as well as between the mountains and the valley, where habitat with mosaics of Scots pine and Mountain pine dominated.

Ograniczanie wyników

1 Polish Journal of Ecology

1 Zeszyty Naukowe. Acta Biologica. Uniwersytet Szczeciński

1 Bylicka M.

1 Ciach M.

1 Kaliciuk J.

1 Wojcieszak H.

1 Wysocki D.

1 2013

1 2009

Wyniki wyszukiwania

Analysis of mallard’s (Anas platyrhynchos) behavior depending on phenology period and the size of the flock on water basins in Szczecin

Relative abundance and flock size of wintering Common Crossbills Loxia curvirostra L. in Western Carpathians: a habitat influence