Distribution, population size and population dynamics of the White Stork (“Ciconia ciconia”) in Cluj County (Romania)

Abstract

During the VII^th International White Stork Census the breeding population of the White Stork was censused in Cluj county. In 2014 at 90 localities 123 White Stork nests were identified. The population of the White Stork in Cluj county was estimated at 110-120 breeding pairs (HPa), and the total density amounted to 1.39 pairs/100 km². The mean distance between each nest and the nearest White Stork nest was 4320.54 m. The majority (55.28%) of the nests were found at altitudes between 300-500 m. Between 1996-2014 there was a moderate increase in the proportion of nests built in the 301-500 m altitudinal range, from 48.61% in 1996 to 55.28% in 2014. During the last 18 years there was a steep increase in the proportion of nests built on overhead electricity line poles, from 59.72% in 1996 to 91.86% in 2014. The average breeding success (JZa) and productivity (JZm) values for the county were 3.12 and 3.38, values which are higher than the estimated JZa and JZm values needed to keep the population stable. In comparison to the last survey in 1996, the 2014 census shows a moderate 5.35% increase in the number of the breeding pairs (HPa).