Issue 2018-2

Ornis Polonica 2018, 59: 89–106

Occurrence of the Great Cormorant Phalacrocorax carbo in the Polish Carpathians during the non-breeding season – the dynamics of passage and numbers in water bodies

Rafał Bobrek, Tomasz Wilk, Aleksandra Pępkowska-Król

Abstract: The paper presents the occurrence of the Great Cormorant Phalacrocorax carbo at 12 main water reservoirs in the Polish Carpathians from August to March and the parameters of spring and autumn migration of the species in the area. Additionally, the two survey methods estimating the dynamics of passage were compared: the visual monitoring of migration at 19 selected points, and counts of birds gathering on water bodies. Both methods indicate that Cormorants were more numerous in the western and central part of the studied area. Spring peak of migration took place in mid and late March. On average 4.9 ind. per 10 h of observation were noted in a single point in spring, with the mean and maximum flock size of 13.4 ind. (SD=19.5; Me=5) and 80 ind., respectively. A total of 97% of Cormorants migrated in spring in the N or NE direction. Autumn migration was more intense – on average 5.8 ind. per 10 h of observation, with mean and maximum flock size in autumn of 14.1 ind. (SD=17.4, Me=7) and 80 ind., respectively. The two migration peaks were noted – in mid October and early November, and 84% of birds migrated in the S or SW direction. The lowest numbers of Cormorants (ca 160 ind.) were noted on reservoirs in August, and the highest numbers (nearly 880 ind.) in October. The winter minimum (ca 210 ind.) occurred in February and coincided with the largest ice cover. The number of Cormorants decreased with increasing ice cover extent on the reservoirs. The period of marked migration and wintering of Cormorants in the studied region covered ca 7 months, from late September to early April. Both methods of assessing the dynamics of migration produced similar results in terms of timing of minimum and peak of the passage. Monthly counts of bird concentrations on reservoirs, however, did not detect short-term changes in the migration intensity, which were registered at observation points. Therefore, if only the Cormorant migration is spatially concentrated, the direct visual monitoring of passage valuably supplements the data collected during counts on water bodies.

Key words: Great Cormorant Phalacrocorax carbo, visible migration, monitoring of migration, winter counts, dam reservoirs, mountains

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Ornis Polonica 2018, 59: 107–118

Distribution and numbers of the Ural Owl Strix uralensis in the Niepołomice Forest

Damian Wiehle, Piotr Sobas

Abstract: The paper presents the current distribution and numbers of the Ural Owl Strix uralensis within the area of the Niepołomice Forest. During each of three breeding seasons (2015–2017) three night counts were conducted between February and April. The second stage included daily visits of sites where the species had been heard at night. Daily visits were carried our between 10 March and 20 April (a total of 22 visits in 2015–2017). Numbers of breeding territories in consecutive study years were: 2015 – 29, 2016 – 21 i 2017 – 25. Considering the past data, the population can be classified as stable. In 2015–2017 1–3 breeding territories (0.65–1.96 pair/10 km2) were found in the complex “Grobla”, as well as 1–3 sites which might have hosted breeding pairs. In the complex “Bór” 8–15 confirmed breeding territories (0.90–1.70 pair/10 km2) and 10–14 potential breeding sites were recorded. No territory was found in complexes “Grobelczyk” and “Koło”, located outside the SPA Natura 2000. This research confirmed a strong breeding territory fidelity of the species. The analysis of distribution of breeding territories indicated the species showed preferences for old-growth forests. The highest breeding densities were found in the areas representing a mosaic of unevenly aged stands, with dominating old-growth forests but also patches of forest nurseries, sapling stands and clearings. The analysis of map clusters revealed that some parts of the Niepołomice Forest contained potentially good breeding habitats, but they were not occupied by the species. This probably resulted from the close proximity to human settlements and the highway A4 in the south of the area.

Key words: Ural owl, Strix uralensis, distribution, numbers, the Niepołomice Forest, map clusters, GIS layers

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Ornis Polonica 2018, 59: 119–153

Rare birds recorded in Poland in 2017

Komisja Faunistyczna

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Ornis Polonica 2018, 59: 154–159

Decline of the Water Pipit Anthus spinoletta population inhabiting montane pastures in the West Beskids (the Carpathian Mts.)

Rafał Bobrek, Tomasz Wilk, Aleksandra Pępkowska-Król

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Ornis Polonica 2018, 59: 159–162

Unusual nesting of the House Martin Delichon urbicum

Marek Bebłot

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Ornis Polonica 2018, 59: 163–168

Waterbird counts in the Bay of Gdańsk in September 2017–April 2018

Włodzimierz Meissner, Katarzyna Stępniewska, Andrzej Kośmicki, Maciej Kozakiewicz, Mateusz Ściborski

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Ornis Polonica 2018, 59: 169–170

Dr Czesław Nitecki (1939–2018)

Dariusz Jakubas

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