Prvi srednjoeuropski nalaz alohtone invazivne vrste amurskog spavača Perccottus glenii u ishrani grgeča Perca fluviatilis

In the spring of 2011,an individual of the rotan, Perccottus glenii Dybowski 1877, was found in the stomach of a European perch, Perca fluviatilis L., captured in a drainage-irrigation channel in eastern Hungary. This is the first recording of the rotan found in the diet of the European Perch in Central Europe.U proljeće 2011. jedan je primjerak amurskog spavača Perccottus glenii Dybowski 1877 nađen u želucu grgeča ulovljenog u drenažno-irigacijskom kanalu u istočnoj Mađarskoj. To je prvi nalaz amurskog spavača u ishrani grgeča u srednjoj Europi

Periodičko pojavljivanje štuka (Esox lucius Linneaus, 1758) u Dunavu u sjeverozapadnoj Vojvodini (sjeverna Srbija)

This study presents the periodical but irregular appearance of pike (Esox lucius L.) in the Danube River and its inundated ponds. During 14 years, 1076 pike were captured at nine sites. The fish appeared in large numbers in years when the average water level was high in spring (R = 0.738, P < 0.01, n = 14). During the study, there were two periods when there were no pike, either in the river or in the inundated ponds. Furthermore, observation showed that prey fish might also affect the presence or absence of pike in late spring in the study area.Rad govori o periodičkom, no nepravilnom pojavljivanju štuka (Esox lucius L.) u rijeci Dunavu i njenim naplavljenim barama. Tijekom 14 godina na 9 lokaliteta ulovljeno je 1076 štuka. Ribe su se u velikom broju javljale u godinama kad je prosječna razina vode bila visoka u proljeće (R = 0.738, P < 0.01, n = 14). Tijekom istraživanja postojala su dva razdoblja kada štuka nije bilo ni u rijeci niti u naplavljenim barama. Osim toga primijećeno je da riblji plijen također može utjecati na prisutnost ili odsutnost štuka na istraživanom području tijekom kasnog proljeća

Ishrana štuke (Esox lucius) u sjeverozapadnoj Vojvodini (Srbija)

We possess little information on diet of the pike (Esox lucius L.) in nearly natural water habitats in the Balkans. Between 2006 and 2010, 528 pike were captured at 20 locations in three different water habitats. The capture of pike was done with an angling system a minimum of four times a month. Pike were mainly caught in autumn with the highest number in october. Furthermore, we also found that feeding intensity was highest in autumn. Altogether 15 prey fish species were recorded in pike stomachs. The most frequent prey fish was the Crucian Carp (Carassius auratus gibelio), followed by the Common roach (Rutilus rutilus) and Common Bleak (Alburnus alburnus). In conclusion, species composition of prey fish and the proportion of vertebrate and invertebrate prey mainly differed from other studies probably due to different geographical areas.Malo je poznato o ishrani štuke (Esox lucius L.) u skoro potpuno prirodnim vodenim staništima na Balkanu. U razdoblju od 2006. do 2010. ulovljeno je 528 primjeraka štuke na 20 lokacija u tri različita vodena staništa. Štuka je lovljena udicom minimalno četiri puta mjesečno. Štuke su uglavnom hvatane u jesen, s najviše ulova u listopadu. Osim toga, u jesen je zabilježen i najveći intenzitet hranjenja. U želucima štuka pronađeno je ukupno 15 vrsta ribljeg plijena. Najčešća riba plijen bila je babuška (Carassius auratus gibelio), slijedile su bodorka (Rutilus rutilus) i uklija (Alburnus alburnus). Zaključeno je da se sastav ribljeg plijena i udio kralježnjaka i beskralježnjaka u plijenu uglavnom razlikuju od drugih istraživanja, vjerojatno zato što su istraživana područja bila geografski različita

Latitudinal, longitudinal and weather-related variation in breeding parameters of Great Reed Warblers in Europe: A meta-analysis

<div><p><b>Capsule</b> Clutch initiation date decreased with longitude, clutch size increased with latitude and decreased with maximum temperature, whereas the number of fledglings increased both with latitude and longitude, and decreased with maximum temperature in 19 European studies of the Great Reed Warbler. Our study confirmed previous findings about the increasing trend in clutch size with latitude, but also found earlier clutch initiation dates and higher number of fledglings longitudinally from west to east, with precipitation closely associated with clutch initiation date and maximum temperature closely associated with the number of fledglings.</p></div

Gniježđenje kukavice (Cuculus canorus), nametnika u gnijezdima, u trščanim staništima SZ Vojvodine, Srbija

We monitored the breeding success of the Common Cuckoo (Cuculus canorus) in four reed habitats (e.g. clay pits, marsh and fishponds, small canals and large canals) in northwestern Vojvodina (Serbia) between 2009 and 2011 (three breeding seasons). A total of 596 Great Reed Warbler (Acrocephalus arundinaceus) nests were found and monitored. The overall parasitism rate for the study area was 0.127, which was calculated from the number of parasitized nests (76) divided by the total number of Great Reed Warbler nests (596). The parasitism rate did not vary with the total number of Great Reed Warbler nests at a study site. The number of parasitized and successful parasitized nests showed significant negative relationship, which means more parasitized nests resulted with more brood lost. The parasitism rate varied significantly among habitats but not among years while the number of successfully parasitized nests differed among both habitats and years. Parasitized nests found in small and large canals showed the highest reproductive success of Cuckoos. Loss of parasitized nests through predation and bad weather circumstances was relatively high in this study compared to other areas.Od 2009. do 2011. godine (tri gnijezdeće sezone) provedeno je istraživanje o uspješnosti gniježđenja obične kukavice (Cuculus canorus) na četiri različita trščana staništa (iskopine, močvare i ribnjaci, mali i veliki kanali) u sjeverozapadnoj Vojvodini (Srbija). Parazitiranje kukavice praćeno je u 596 gnijezda velikog trstenjaka (Acrocephalus arundinaceus). Stopa kukavičjeg parazitiranja za cijelo istraživano područje iznosila je 0.127, a izračunata je tako što je broj parazitiranih gnijezda (76) podijeljen s ukupnim brojem nađenih gnijezda velikog trstenjaka (596). Pojedinačno po istraživanim lokacijama broj parazitiranih gnijezda nije varirao zajedno s ukupnim brojem gnijezda velikog trstenjaka. Broj parazitiranih gnijezda je bio u negativnoj korelaciji s brojem uspješnih parazitiranih gnijezda, tj. što veći je broj parazitiranih gnijezda, više je propalih. Stopa parazitiranja varirala je značajno između staništa, ali ne između godina, dok je broj uspješno parazitiranih gnijezda značajno varirao između staništa i godina. Parazitirana gnijezda nađena na malim i velikim kanalima su rezultirala s najvišom reproduktivnom uspješnosti kukavice. Broj propalih gnijezda zbog predacije i loših vremenskih prilika u ovom je radu, u usporedbi s rezultatima drugih izvora, relativno visok