The morphometric analysis of Eurasian coot eggs (Fulica atra) under the local conditions from Câmpenești, North-Western Romania

The aim of the present paper was to analyze the measurements of the Eurasian Coot (Fulica atra) eggs in order to evaluate if the local conditions, presented here, differ in some way from older data found in references dating to 1955 in Romania. The data were collected from the Eurasian Coot nests identified (N=8) at Câmpenești fishponds, located in North-Western Romania, in May 2018. The clutch size was 7.5 ±1.6, ranging from 5 to 10 eggs. The mean egg length was 50.81 mm, and the mean egg breadth was 34.5 mm with higher variability in case of the first measurement. The mean egg volume was 31.3 cm3 which is much smaller than reported in the Romanian references (36.13 cm3). Regarding intra-clutch variance, we found that some clutches manifest a higher length, breadth and volume variance than others which can be a result of the intraspecific nest parasitism or environmental variances. The results brought some extensions of egg length and egg breadth limits and also may reflect a decrease in egg size over time.

New species on the list of species with intraspecific nest parasitism

Intraspecific nest parasitism has only recently received more attention from ornithologists. In 2001, Yom-Tov published a list of 234 species that had exhibited this behaviour. I have since found literature data on four additional species in which intraspecific nest parasitism has been observed. No such record has so far been published from Hungary. This study presents records on 25 species from Hungary and on one species from Croatia, out of which I have not found any reference for intraspecific nest parasitism in the literature for Cattle Egret (Bubulcus ibis), Eurasian Thick-knee (Burhinus oedicnemus), Black-winged Stilt (Himantopus himantopus), Collared Pratincole (Glareola pratincola), Mediterranean Gull (Larus melanocephalus), Little Tern (Sternula albifrons), Whiskered Tern (Chlidonias hybrida), Eurasian Roller (Coracias garrulus) and Eurasian Jackdaw (Corvus monedula). In addition to records from Hungary, for Black-headed Gull (Larus ridibundus) and Mediterranean Gull I also present observations from Slovakia, and for Common Shelduck (Tadorna tadorna) from Germany.

New record of intraspecific nest parasitism by the Silky Starling (Sturnus sericeus)

The Silky Starling (Sturnus sericeus) is endemic to East Asia and little is know about its’ breeding ecology. We found intraspecific nest parasitism (INP) by this species in a reproductive study conducted from March to June 2011. We found three nests were parasitized using the obvious morphological differences or partition of egg-laying. One egg appeared 3 days after the 26th female had finished laying eggs. One egg was different in color from the other five eggs in the 27th nest. The third instance was discovered in the 37th nest after the fledglings had fledged. Our findings confirmed INP by the Silky Starling.