Plastering mud around the entrance hole affects the estimation of threat levels from nest predators in Eurasian Nuthatches

Background For cavity-nesting birds, the nest entrance plays an important role in preventing predators from accessing nests. Several species of nuthatches use mud to narrow the entrance of cavities. In theory, the smaller the entrance hole size, the more effective it is against predators; however, few studies have tested whether narrowing the entrance hole size can affect the estimation of threat levels from nest predators in cavity-nesting birds. Methods Using dummy experiments, we tested whether Eurasian Nuthatches (Sitta europaea, narrow the entrance hole of cavities) and Cinereous Tits (Parus cinereus, do not narrow the entrance hole, as a control) perform different nest defence behaviours against Common Chipmunks (Tamias sibiricus, small nest predator) and Red Squirrels (Sciurus vulgaris, larger nest predator). Results Both nuthatches and tits exhibited stronger response behaviours (high dummy response scores) against chipmunks than against squirrels. Compared with tits, nuthatches exhibited more aggressive behaviours to chipmunks, but their responses to squirrels were similar. Conclusions Nest defence behaviours of nuthatches to chipmunks differed from tits, and the results suggested that nuthatches might estimate threat levels of nest predators according to their narrowed entrance-hole size.

ШТУЧНІ ГНІЗДІВЛІ ДУПЛОГНІЗДНИХ ПТАХІВ В ЯКОСТІ БЕЗПЕЧНОГО СЕРЕДОВИЩА ДЛЯ РОЗВИТКУ ПРЕДСТАВНИКІВ DIPTERA

Досліджено представників двокрилих (Diptera) у гніздах дуплогніздників у штучних гніздівлях на території ландшафтного парку "Фельдман Екопарк" у Дергачівському районі Харківської області. Проаналізовано та виявлено комплекс субстрату для безпечного середовища розвитку представників двокрилих, наведено кількісні показники та статистичні дані 123 пупаріїв двокрилих. Найбільше пупаріїв виявлено у гніздах синиці великої Parus major, менше у мухоловки білошийої Ficedula albicollis і повзика звичайного Sitta europaea.

Territorial Responses of Nuthatches Sitta europaea—Evaluation of a Robot Model in a Simulated Territorial Intrusion

In birds, aggressive behavior can be elicited in the field with a simulated territory intrusion (STI). Here, we compared four different STI methods in nuthatches in the non-breeding season: playback only, playback combined with an inactive wooden model mounted on a robot device, playback and an active model mounted on a robot device, and playback with the robot device only. In the control treatment, birds were not exposed to STI. Experiments were carried out in 12 territories. Behavioral observations included latency to approach, latency to start calling, time spent in the same tree, number of flyovers, minimum distance, number of individuals, number of flights into the tree, and number of calls. There was no significant influence of stimulus presentation. Nuthatches responded equally to all four experimental manipulations, but order of presentation had a strong influence.

The first record of the trematode Urogonimus certhiae (Trematoda: Leucochloridiidae) in the Eurasian nuthatch Sitta europaea

Adult trematodes of the genus Urogonimus Monticelli, 1888 were found in the cloaca of a male Eurasian nuthatch Sitta europaea Linnaeus, 1758, the carcass of which was found in the Vyritsa Settlm. (Leningrad Prov., Northwest Russia). Based on morphological characters, the worms were identified as U. certhiae McIntosh, 1927. This is the first record of this parasite from the nuthatch and from Northwest Russia. We analysed nucleotide sequences of ITS1-5.8S-ITS2 rDNA of this species and found important differences with U. macrostomus (Rudolphi, 1803). Genetic and morphological data indicated that U. certhiae and U. macrostomus were two separate species. Phylogenetic analysis confirmed that Urogonimus and Leucochloridium Carus, 1835 were two distinct genera.

Cases of occasional interspecific brood parasitism and egg dumping in Hungary

There are numerous publications in the ornithological literature on mixed-species broods, i.e. on cases when a species lays some or all of its eggs into the nests of other species. This phenomenon, known as brood parasitism, has not yet been studied in Hungary. Here, I use the term brood parasitism, but I could not separate cases of egg dumping, a reproductive error by females. Based on literature and my own observations, I found evidence for interspecific brood parasitism in 28 species breeding in Hungary, not including the cases of the obligate interspecific brood parasite, the Common Cuckoo (Cuculus canorus). Only one of these belongs to passerines, while in the rest of the cases, this phenomenon occurred in representatives of non-passerine families. However, cases of brood parasitism and nest parasitism have to be treated separately. The latter refers to cases when a species occupies a nest, usually a nesthole or nestbox, already containing eggs of another species, and lays its own eggs next to the foreign eggs. The present study provides data on European Roller (Coracias garrulus), Northern Goshawk (Accipiter gentilis), Common Kestrel (Falco tinnunculus), Red-footed Falcon (Falco vespertinus), Eurasian Hobby (Falco subbuteo), tit species (Parus, Cyanistes, Poecile spp.), Eurasian Nuthatch (Sitta europaea) and Eurasian Tree Sparrow (Passer montanus), but in all likelihood the number of species involved is much higher.