Nature Protection and Study Society NATURA

Sombor, Serbia

Nature Protection and Study Society NATURA

Sombor, Serbia
SEARCH FILTERS
Time filter
Source Type

Dapic D.,Nature Protection and Study Society NATURA | Mero T.O.,Hungarian Academy of Sciences
Acrocephalus | Year: 2016

Grasslands host a high diversity of plant and animal species. In Serbia, most alkali grasslands are located in the province of Vojvodina. The majority are not subject to conservation. The aim of the study was to investigate the relationship between the proportion of croplands and (1) the number of breeding species and (2) the number of breeding pairs in the alkali grasslands of the upper Mostonga River catchment basin (NW Serbia). The size of the study area was 400 ha. Birds were surveyed along seven parallel transects eight timesper breeding season. Lengths of the cross sections of both grasslands and croplands were measured. The proportion of croplands per transect was calculated by dividing the total length of cross sections of croplands by the total length of transect. The relationship between the proportion of croplands and the number of breeding pairs and the number of breeding species, respectively, was studied using simple linear regression. We recorded a total of 171 nesting pairs belonging to 23 species in the alkali grassland investigated, with breeding densities between 2.2 and 10.3 pairs per 10 ha. The number of species per transect ranged between 6 and 11. The most abundant species were Skylark Alauda arvensis, Yellow Wagtail Motacilla flava and Corn Bunting Emberiza calandra. The numbers of breeding pairs (F6 = 21.761, P < 0.0001) and of breeding species (F6 = 13.758, P = 0.001) were both influenced negatively by the proportion of croplands. These findings highlight the need for coordinated conservation measures on the alkali grasslands of Vojvodina.


Mero T.O.,Nature Protection and Study Society NATURA | Mero T.O.,Hungarian Academy of Sciences | Zuljevic A.,Nature Protection and Study Society NATURA
Turkish Journal of Zoology | Year: 2017

We present a method for estimating nesting population size in a passerine bird based on counts of active nests, which can provide more accurate estimates on true population size than other methods. We surveyed 5 different reed habitat types in a region of Serbia in 2009–2011 to estimate the population size of the Great Reed Warbler. The estimation was based on the counts of active nests and was limited to the first clutches laid by females. We recorded a total of 442 nesting females. To estimate the population size for the studied region, the nesting densities were multiplied by the total area of the reedbed and the mean proportion of reed cover in each reedbed. This method may be used in areas/countries where there are no regular censuses and in bird species with strong habitat affiliations. In contrast to other methods, our estimation excludes uncertainty due to the presence of floater males and double counting of singing males, but considers polygyny, overall improving the accuracy of the estimate of the nesting population size. The disadvantages are that the method is time-consuming and demands considerable effort and reliable data on habitat area and quality. © TÜBİTAK.


Mero T.O.,Debrecen University | Zuljevic A.,Nature Protection and Study Society NATURA | Varga K.,Debrecen University | Bocz R.,Hortobagy National Park Directorate | Lengyel S.,Hungarian Academy of Sciences
Turkish Journal of Zoology | Year: 2014

In this study, we present the effects of reed burning and precipitation on the breeding success of Great Reed Warblers on a mining pond (2008-2011). Breeding success, i.e. the probability that an egg would produce a fedgling, was 0.43. Clutch survival was lowest in 2010, due to the precipitation and high water level during the season. Breeding success was higher in the second half of the breeding season, although in 2008 and 2011 precipitation was also higher in the second half than in the first half of the breeding season. During the first half of the breeding season, daily egg and nestling survival did not differ. However, in the second half of the breeding season, daily egg survival was higher than daily chick survival. In years when reed was burned, breeding density varied between 7.7 and 12.3 pairs ha-1, which was not significantly lower than in years when reed was not managed (average: 13.2 pairs ha-1). Despite the availability of fresh reed in large areas, birds placed their nests mainly in mixed reed stands. Breeding success in fresh and mixed reed did not differ. Generally, breeding success and density were not affected by reed burning, but water level affected breeding success and density. © TÜBİTAK.


Mero T.O.,Nature Protection and Study Society NATURA | Zuljevic A.,Nature Protection and Study Society NATURA
Acta Zoologica Bulgarica | Year: 2015

Previous attempts to determine the age of the great reed warbler, Acrocephalus arundinaceus, after the complete moult have exposed a number of uncertainties. The present study provides evidence that the age of adult birds of this species cannot be determined precisely by using the colours of the iris and the tarsus as well as by the presence or absence of tongue spots. Between 2008 and 2014, we ringed a total of 2783 individuals (1445 adults and 1338 nestlings) and 76.5% of the captured adult birds had olive-green irises. Recaptures revealed that the colour of the iris changed from olive-green to reddish-brown in 19.7% of the individuals and the change in the opposite direction was similarly frequent (21.3%). In 57.4% of the cases, the iris colour remained constant throughout the years. As the nesting season progressed, the colour of the tarsus changed from bluish-grey to flesh-pink, while the presence or absence of tongue spots did not display any trend. The most frequent combinations were an olive-green iris, a bluish-grey or flesh-pink tarsus and the presence of tongue spots. In birds of exactly known age (ringed as nestlings; n = 25), the combinations of the three variables varied strongly. Furthermore, the changes in the three variables did not demonstrate any relationship with the increasing age of the individuals. Our results suggest that these criteria may not be suitable for age determination, and a more reliable method is needed. At the same time, we advise that aging criteria should be verified in advance for birds of exactly known age before applying them to unknown individuals.


Mero T.O.,Debrecen University | Zuljevic A.,Nature Protection and Study Society NATURA | Varga K.,Debrecen University | Lengyel S.,Debrecen University
Natura Croatica | Year: 2013

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 arun- dinaceus) 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.


Mero T.O.,Nature Protection and Study Society NATURA | Zuljevic A.,Nature Protection and Study Society NATURA
Ethology Ecology and Evolution | Year: 2015

Knowledge of the effects of nest position with regards to distance from shore and vegetation structure on the nest defence behaviour of Great Reed Warblers is lacking. Nest defence behaviour was investigated in the case of 110 monogamous breeding pairs during the breeding season of 2011. We found that nest distance from shoreline and from the reed edge adjacent to water, and reed density, influenced nest defence behaviour positively. However, time elapsed since hatching did not affect parental behaviour. Similar to what was found in previous studies, females defended nests more intensively. Previous papers reported higher predation pressure near both reed edge types (near shoreline and water) than in interior parts of the reed bed, and considering these and our results we suggest that the nest defence pattern of monogamous Great Reed Warblers may vary similarly near both edge types, while in the case of interior parts of reed beds further studies are required for proper conclusions. © 2015 Dipartimento di Biologia, Università di Firenze, Italia


Mer T.O.,Nature Protection and Study Society NATURA | Zuljevic A.,Nature Protection and Study Society NATURA | Lengyel S.,Hungarian Academy of Sciences
Bird Study | Year: 2015

Capsule 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. © 2015 British Trust for Ornithology.


Mero T.O.,Debrecen University | Zuljevic A.,Nature Protection and Study Society NATURA
Acta Zoologica Bulgarica | Year: 2014

The migration of tits has been the subject of a number of studies, whereas very little is known as concerns their movements in their wintering areas in urban habitats. This study presents the effects of weather variables (the air temperature, the number of days with a snow cover and the amount of precipitation) on the distances moved by the Great Tit Parus major and the Blue Tit Cyanistes caeruleus in an urban habitat during autumn and winter. Ringing data from 32 successive years (1981-2013) in Sombor, Serbia, were used. The Great Tits proved to move larger distances, searching the entire town, while the Blue Tits rather moved only within particular areas of the town. The female Great Tits moved significantly larger distances than the males, while such a difference between the sexes was not observed in the Blue Tits. Neither the number of days with a snow cover nor the air temperature affected the distances moved in either species, whereas a higher amount of precipitation led to shorter distances moved in the Great Tits but not in the Blue Tits. The movement activities of the Great Tits were lower in periods when precipitation was frequent.


Mero T.O.,Debrecen University | Zuljevic A.,Nature Protection and Study Society NATURA
Acta Zoologica Bulgarica | Year: 2014

The effects of physical variables of the reed (e.g. the diameter and density of the reed stems) on the breeding success of the Great Reed Warbler were studied in the cases of the nest-supporting reed stems and the stems in the surroundings of 124 nests in three different reed habitats (mining ponds, small canals and large canals). The mean diameter of the nest-supporting stems correlated positively with the mean diameter of the stems in the surroundings. The diameters of both the nest-supporting reed stems and the stems in the surroundings varied significantly between the three reed habitats, whereas the density of the stems in the surroundings did not. We subdivided the reed densities into three categories: "sparse" (50-160 stems/m2), "intermediate" (160-270 stems/m2) and "dense" (270-380 stems/m2). The Great Reed Warbler significantly preferred the intermediate reed density for breeding, while the highest breeding success was recorded in the dense reed. However, the clutch survival did not differ between the three reed density categories. Whereas the intermediate reed density was mostly used by the Great Reed Warbler for nesting, this was not the subgroup with the highest breeding success, probably because of the different predation types.


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. © 2016, Croatian Natural History Museum. All rights reserved.

Loading Nature Protection and Study Society NATURA collaborators
Loading Nature Protection and Study Society NATURA collaborators