New findings of trematodes of the superfamily Echinostomatoidea Looss, 1899 in birds from the Czech Republic

Summary In the Czech Republic, 12 freshly dead birds belonging to four species were examined helminthologically during a period of 2015 – 2019. They were six Caspian gulls Larus cachinnans (Lariformes), three goosanders Mergus merganser (Anseriformes), two common snipes Gallinago gallinago, and one common curlew Numenius arquata (Charadriiformes). Concerning trematodes, five echinostomatoids species were found, namely Aporchis massiliensis (obtained from one positive Caspian gull), Echinoparyphium macrovitellatum (one positive from six Caspian gulls), Echinostoma academica (one positive common curlew), Echinostoma stantschinskii (one positive from two common snipes), and Echinochasmus mergi (one positive from three goosanders). All the five echinostomatoids species represent the first records for the helminth fauna of the Czech Republic; the fl ukes A. massiliensis and E. macrovitellatum are recorded for the first time in the Central Europe or the Europe at all, respectively.

Long-eared Owl Asio otus breeding in a Caspian Gull Larus cachinnans colony: Reversed roles in protective nesting association?

We describe the event of Long-eared Owls Asio otus nesting on an island within a colony of Caspian Gulls Larus cachinnans at the Mietków Reservoir (SW Poland). The owls nested in an old (possible corvid) nest in a willow and raised two owlets. They probably did not hunt gulls, neither adults nor chicks. We suggest that, in this case, the Long-eared Owls benefitted from breeding within a gull colony because of the added security against predators that the gulls provided.

Short report on probable case of Caspian Gull predation on migrating swallows observed at first time

At Mietków Reservoir (SW Poland), during the breeding season of 2019, we found 52 dead swallows in Caspian Gull (Larus cachinnans) colony. Most of them were Barn Swallows (Hirundo rustica). The bodies of swallows were fresh and torn with traces of bill. We assume that swallows might have been in weak condition and hunted by gulls. They also could die because of bad weather conditions and hypothermia, fell into the water and then were taken. However, to our knowledge, it was the first mass event of feeding on migrating birds by Caspian Gull.

Recent Data on the Danube Delta (Romania) Avifauna from the 2014 and 2015 Summer Seasons

A number of faunistically interesting observations related to the avifauna of the Danube Delta (Romania) are presented. In the spring of 2015, a mass mortality event with a minimum of 118 dead birds occurred in a major Dalmatian Pelican Pelecanus crispus colony in the Black Sea lagoons caused by the avian flu virus, strain H5N1. A possible hybrid between Little Egret Egretta garzetta and Western Reef Heron Egretta gularis was observed. The first nesting of Ruddy Shelduck Tadorna ferruginea in the Danube Delta was documented. Goldeneye Bucephala clangula and Smew Mergus albellus are re-colonising the areas they abandoned in the early 20th century. New data regarding the relocation of Pallas’s Gull Larus ichthyaetus colony in the Danube Delta as a result of hydromorphological changes in the bay, nesting and defence strategies against Caspian Gulls Larus cachinnans are described. Probable nesting of Citrine Wagtail Motacilla citreola in the Danube Delta was documented in 2014 for the first time.