Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: terns

Sortuj według:

Ogranicz wyniki do:

Changes in the abundance of charadriiformes in Central Namibian Coast: a comparison of austral summers 1976/1977 and 2016/2017

Kopij Grzegorz

Polish Journal of Ecology

2023

Vol. 71, nr 2-3

75-86

In 2016/2017 austral summer, individuals of all charadriiform species were counted on selected sections of the Atlantic coastline between Cape Cross and Walvis Bay in Namibia, southern Africa (in total 72 km of coastline). Results were compared with similar data obtained in these sections forty years earlier (1976/1977 austral summer). Most wader species have showed decline, while most gulls and terns – increase in numbers. In overall, the Palearctic waders were more numerous in 1976/1977 (N = 9523 birds) than in 2016/2017 (N = 1164 birds) by the order of magnitude. In both periods the most numerous species were the ruddy turnstone Arenaria interpres and sanderling Calidris alba. Among Lari, numbers of Damara tern Sternula belaenarum has decreased by the order of magnitude, numbers of the kelp gull Larus dominicanus has significantly increased, while numbers of Hartlaub's gull Larus hartlaubii remained similar in both years compared. All these gull species are breeding residents in Namibia. The only Palearctic tern species, the common tern Sterna hirundo was vagrant in 19976/1977, while in 2016/2017, it was not recorded at all. Changes in the number of Palearctic shorebirds recorded in the coastline between Cape Cross and Walvis Bay may could have been caused probably mainly by human disturbance. Changes in numbers of waders in other wintering places in South Africa were also reviewed.