Suchergebnisse

The monitoring of population state of White Stork (Ciconia ciconia L.) in the National Nature Park "Pyriatynskyi" and surrounding area was
carried out in 2014–2019. The number of nests in the area was counted and the nest site selection were investigated. A breeding success analysis was also conducted. There were from 86 to 102 nests occupied by storks observed for a six-year study period. The mean number of fledglings in relation to all nest occupying breeding pairs (JZa) was 2,43 ± 0,04 (n = 570), and in relation to breeding pairs with nestlings (JZm) was 2,75 ± 0,04 (n = 502). The percentage of unsuccessful pairs was 10,07 % (%HPo). In different years, breeding success (the proportion of successful pairs with fledglings) ranged from 78,43 % in 2017 to 98,94 % in 2015. The majority of pairs fledged 2 (34,93 %) or 3 (36,92 %) young, that makes 71,85% of broods for total. Broods of 5 nestlings, which is the maximum value for the study area, are rare and registered not every year. Only 4,44% of the total number of such nests was identified for six years. During 2015–2016 storks hatched a smaller number of nestlings, but far more successfully fledged them than in the previous year 2014 and subsequent 2018–2019 years. The year 2017 became the most unfavorable for stork breeding in the region of the park – birds raised the smallest number of fledglings, and the proportion of unsuccessful pairs was the largest for the years of observation. All found nests of a White Stork are located singly within the boundaries of settlements. The preferred nest site is on poles (69,29 % of the total nest number), other types of placement are less common (trees, buildings of various types, water towers and artificial nests). 10 or more nests of storks were recorded in the villages Deimanivka, Povstyn, Antonivka, Usivka and Kaplyntsi located in the floodplain of the Udai river. The average density of nests per settlement was 1,7 ± 0,3 km2.

AbstractThe white stork Ciconia ciconia is a bird species located at the top of the trophic pyramid in grassland and wetland ecosystems. This charismatic species is susceptible to pesticides and their environmental residues. In 2016, we collected blood samples from 114 white stork chicks across Western and Southern Poland. Chicks were sexed by molecular analysis and aged by development pattern. We studied the relationship between the concentration of pesticides (beta-HCH, heptachlor, aldrin, endrin, 4.4′-DDD, 4.4′-DDE and 4.4′-DDT) and of PCB in the chicks' blood with blood morphology and biochemistry parameters in the blood. The mean (± SD) values of concentrations of above detection level pesticides were: for (1) beta-HCH 4.139 ± 19.205; (2) 4.4′-DDE 9.254 ± 91.491 and additionally (3) PCB 16.135 ± 44.777 ppb. We found negative relationships between beta-HCH and oxidative stress enzyme activity in the blood, between beta-HCH and leukocyte concentration and between 4.4′-DDE and catalase activity. We also found a positive relationship between the concentration of pesticides in blood and the age of chicks. Interestingly, we found a higher concentration of PCB in the blood of male stork chicks than in female stork chicks. We provide more evidence that the presence of pesticides in the environment can be a strong stress factor, shaping the health status of birds.

The white stork Ciconia ciconia is one of the most emblematic birds in rural habitats of Europe. Its populations showed a drastic decline during the 20th century, followed by a rapid recovery in the last decades. The population increase has led to a relaxation in the specie's monitoring effort, the last Spanish national official census having been conducted more than 15 years ago. In order to update this knowledge, this study shows the results of a breeding population census conducted in Navarre during the spring of 2018, describing the preferences in nest location, and comparing the current breeding population size with that described in the literature published since 1960. Our results show a breeding population of 739 pairs, which is the highest value ever recorded. However, this increase in the number of pairs has not been associated with a significant expansion of the specie's distribution area, which is still limited to the southern half of Navarre. The only relevant colonisation would be the 5 pairs established in the Pamplona district. Most pairs (86.3%) nested in colonies, with an average size of 9.2 nests. Most of the nests were located in trees (49.0%), followed by buildings (28.8%), cut trees (10.0%), pylons (6.9%) and other types of structures (antennas, chimneys, artificial nests, cranes..., 5.3%). A comparison of the current situation with previous censuses shows that there has been an annual population growth rate of 6.6%, with an important change in nesting habits, both in the percentage of pairs that nest in colonies and in the substrate selected to build the nest. The possible causes that could explain these changes and the conservation implications for the species are discussed.

Aristotle in his anatomical observations is marking the beginning of functional anatomy followed by Georges Cuvier that formulate the low of the correlation of parts. According with this we can expect that the digestive system structures tend to be similar between species that consume approximately the same type of food. In this study we chose to evaluate macroscopic the digestive system of two different zoophytophagous species, with similar body size but different life behavior and feeding strategies: White Stork (Ciconia ciconia) and Common Buzzard (Buteo buteo). Data were collected after the dissection of 10 carcass (5 White Stork and 5 Common Buzzard). The digestive tract and its structures were measured and weighed. In common buzzard the beak is strong and short adapted for the laceration of the prey. In white stork the beak is long, strong, straight adapted to capture prey like a harpoon. In both species, the esophagus is located on the right side of the neck, the length is different, proportional to the neck. In common buzzard the crop is present and absent in white storks. The cuticle or koilin layer is highlighted in white stork compared to common buzzard. In common buzzard, the small intestine is reduced in size, without marked transition between the duodenum and the ileum. The white storks have a long small intestine with many loops, with no transition between the segments. In both species, the cecum is reduced in size and has a vestigial appearance; the colon is reduced in size, and extends from the level of the ileo-colic junction to the cloaca. The digestive system is adapted to a strictly carnivorous diet and the differences identified between the anatomical structures of the digestive tract of the two species are correlated with the differences of their feeding behavior.