Volumen 29 (2021): Edición 2 (December 2021)

The Old Lake of Tata, an important wild goose roosting site in Central Europe, is unique in its location being in the middle of a city with a population of 24,000. Consequently, the site is subject to intensive human disturbances. Goose migration and wintering on the lake was studied for over 37 years (1984–2021). In addition to weather, hydrological, and feeding conditions, particular attention was focused on human influences (which were deemed generally disruptive, but also beneficial in some cases) that can induce significant changes in the population dynamics of the 30,000–50,000 wild geese from 13 species wintering here. Almost without exception, the largest observed changes in the abundance of wild geese roosting overnight on the Old Lake are due to anthropogenic effects. In the majority of cases, the most significant population changes are due to impacts associated with the operation and upkeep of the lake and the New Year’s Eve fireworks. As a result, the winter operation of the Old Lake has been regulated by the Wild Goose Preference Mode since 2011, and the City of Tata has banned the use of fireworks during the winter period since 2018. Consequently, the conditions for wild goose migration have improved significantly. However, the situation of the Old Lake is still quite fragile and more conservation measures are needed to protect it further.

The present study attempts to assess the composition, abundance and diversity of avifauna with respect to their habitat in and around the Purbasthali wetland, based on both primary data collected through the point count method during 2017–2019 and literature data. Among the total 77 species (encompassing 10 orders and 19 families), 39 species are migrants, 18 are rare and 24 species show declining global trend. According to their habitat, they are sub-divided into three categories i.e. waterfowls (live in open water, 20 species), waders (live in bank areas/water edge area, 45 species) and wetland associated (live in nearby trees, 12 species). The Shannon-Wiener Diversity Index (H’) and the Evenness Index (E’) are used to examine the diversity within and between the habitats. The result reveals higher diversity and evenness of the waders in comparison to others. The maximum diversity (H′=3.02) and evenness (E′=0.79) has been recorded for the waders in 2019, whereas the least values (H′=1.02, E′=0.34) have been found in 2016 for the waterfowls. Relative Diversity Index affirms the dominance of the Anatidae family. The birds of the area have now been seriously threatened by human intervention.

Forest plantations are a relatively new environment in Chile, with impacts of different magnitude on different taxa. Birds are one of the taxa mostly used as ecological indicators to evaluate the effect of different types of disturbances, due to their level of specialization in the use of different microhabitats. We assessed the effect of the age of Pinus radiata plantations (2 sites of 8 and 12 years, respectively) and seasonal (three seasons) on the diversity of bird assemblages. The abundance of species from both sites was assessed through acoustic and visual survey records, which were also compared at trophic guild level. Differences were observed at both sites, with higher diversity calculated for Cerro Ñielol (8 years) compared to Rucamanque (12 years). In seasonal terms, diversity was not affected in Cerro Ñielol, while in Rucamanque significant differences were observed during fall. Guild composition of both localities also showed differences, resulting in higher diversity for Cerro Ñielol in most cases. Despite the fact that the younger plantation presented the highest diversity, elements associated with the landscape are discussed, as well as particularities in the use of space by the species.

The field biology of Chukar Partridge (Alectoris chukar) was studied in Malakand division, which is an important range of its distribution in Pakistan. The abundance of the species at different altitudes was studied using both transect trails of various lengths and point counts at certain spots. The average monthly population density was estimated to be 1.448±0.466 birds/ha. The population density in August, September, and October 2020 was significantly (P<0.05) higher, as compared to the rest of the months. Chukar Partridge sightings were the lowest in December, with mean±SD = 0.996±0.147 birds/ha and the highest in October 2.333±0.202 birds/ hae in all the study sites. At each study site, maximum activity habitats were marked and selected for breeding ecology study. Data was collected on breeding time, nest site selection, nest size, incubation period, and hatching success. The breeding season in this species starts in February, with the peak months being March and April, when calls are frequently heard. The frequency of calls varied from 0.15 to 0.3 per minute. Throughout the breeding season, twelve nests were observed using binoculars and camera traps from a distance to avoid disturbance, wherever possible and without disrupting the species. Nesting sites were mostly on slopes under the eaves of Dodonea viscosa, Calotropis procera and Zizyphus oxyphylla. Dry leaves of Poa annua, Cynodon dactylon, Dichanthium annulatum, small twigs of bushes, and downy feathers were used as nesting materials. The average diameter of nest (n=12) was 25.43±3.4 (mean±SD) cm. Overall, the mean clutch size was 94.5±30.187 egg/nest with an incubation period of 22–24 days. The hatching success rate was 82% with 315 successfully hatched chicks, while the fledging rate was 83% (265 fledged out of 315 hatched in, n=42 nests).

The Eastern Imperial Eagle (EIE) is a large-sized, globally threatened species with a wide distribution. The species is extremely vulnerable and sensitive to human disturbance and activities in the vicinities of its nests. We analyzed the effect of human disturbance in two territories of Eastern Imperial Eagles from Bulgaria in 2008–2009. We recorded 375 cases of different types of human activity in the vicinities of the two surveyed nests – 60 cases in nest A and 315 in nest B. The most common activity around the studied nests was the passing of light motor vehicles (n=100 cases). Our results highlight that the probability of EIE’s reaction is dependent on the type of activity, distance from the nest and the duration of the activity. However, eagles’ reaction is independent from the number of intruders. We found that with the decrease of the distance to the nest, the reaction progresses and is more acute. We found statistical differences between the distance belts and the majority of alert and flight reactions that were recorded at distances up to 300 m from the nests. We reported that humans walking around nests (mainly hunters, fishermen, tourists, people illegally extracting sand in the close vicinities of the nests) result in a large number of reactions of flight off by the eagles thus, leaving the nest unattended. More research on a large scale on this topic is needed including more accurate measures to address human disturbance in EIE territories. The findings will be applied to ensure higher breeding rates and species conservation.

The spatial ecology of the Eurasian Griffon Vulture (Gyps fulvus) has been a subject of scientific interest for long due to its conservation status, critical ecosystem role, gregarious lifestyle and complex foraging behavior. The trans-border Eastern Rhodope Mountain in Bulgaria and Greece holds an increasing population of the species and one of the largest on the Balkan Peninsula. We used high-frequency GPS data from 13 Griffon Vultures from this population to study their movements, home range size and its seasonal or age specific dynamics. The overall foraging home range (95% kernel) was 3,204 km² and the core area of activity (50% kernel) was 256.5 km². We found high seasonal variation of the home range size. Vultures were foraging over larger areas in the summer and spring but their activity was limited to four times smaller areas in winter. We found no age specific variation in the home range sizes but the non-adult vultures showed tendency to conduct exploratory movements far from the breeding colony. Our results can be used for planning conservation efforts in the areas of high importance for the species.

The authors compared the first phalanx of the second wing finger of 33 European diurnal raptors. The importance of studying this bone lies in the fact that, although it has diagnosable characteristics, it was practically neglected by osteologists and paleontologists. Thus, fossil materials can be identified through them, as well as those from owl pellets. The comparison was made possible by the comparative avian skeleton collection of the Hungarian Natural History Museum. In a preliminary investigation we examined the morphological diversity of the first phalanx of the second wing finger among the different species. We used principal component (PC) analyses on measurements. The PC described the curvature of the anterior surface of the bone and the relative size of the distal and proximal epiphyses. The principal component analysis showed slightly overlapping in shape between the taxons but the accipitriform and falconiform birds diverged in the morphospace. The attributes and geometry of the first phalanx of the second wing finger reflects more on taxonomic background than flying behaviour. The avian wing is a complex and highly modulable structure, therefore, probably body mass and size affect flying performance than the other morphological features of this bone. The text is supplemented by 6 figures and one size table.

Nestboxes are widely provided as nesting sites for hole-nesting birds, yet the relative contribution of nestbox characteristics and habitat quality in determining the occupancy rates and breeding success of birds remains unclear. We provided nestboxes in deciduous woodlands in England and examined if those nestboxes were erected in random orientations and whether the orientation of nestboxes and habitat quality, in the form of tree density, influenced their occupation by, and breeding success of, Blue Tits (Cyanistes caeruleus), Great Tits (Parus major) and Pied Flycatchers (Ficedula hypoleuca). We found that first, the nestboxes were erected non-randomly orientated towards the north and east, and away from the south and west. Second, the occupation rates of none of the species was related to nestbox orientation or tree density. Third, the breeding success of neither Blue Tits nor Great Tits varied with tree density but did vary with nestbox orientation. Blue Tit hatching success and fledging success was higher in nestboxes facing south than in other directions whilst in Great Tits, clutch sizes, hatching success and fledging success was higher in nestboxes facing south than nestboxes facing other directions. Our results suggest that nestbox characteristics, such as orientation, have more influence on the reproductive success of passerines than habitat quality. This further suggests that conservationists should orientate nestboxes southwards in order to maximise their benefit to birds in temperate climates during the breeding season.

The paper describes investigations on the reproduction biology (nesting, clutching, hatching, fledglings` departure) of the Common Redstart (Phoenicurus phoenicurus) in artificial nest boxes (AN) in Northeastern Ukraine. There were three sites of research: Hetman NNP, NPP “Gomilshansky Forests”, and RLP “Feldman Ecopark”. The research was performed during the nesting period from the first week of April to the first week of July in 2015‒2020. Annually, 5‒8 bird counts were conducted at each site. The first complete egg clutches at Hetman NNP were observed from 08.05 to 17.05 (2015‒2020) and at NPP “Gomilshansky Forests” from 02.05 to28.05 (2017‒2020). Dates of the first egg laying, at various conditions, had inter-annual variability because of unstable weather conditions in May. The average parameters of nests in AN at Hetman NNP were the following: diameter of nests (D) ‒ 124.1±6.3 mm; diameter of trays (d) ‒ 61.5±1.7 mm; nest height (H) ‒ 63.5±9.4 mm; depth of trays (h) ‒ 48.6±2.7 mm; nest mass (m) ‒ 43.7±3.8 mm. The size of complete clutches in Northeastern Ukraine was calculated when eggs were incubated. According to the average indicators, during 2015‒2020, the average size of the clutch was 6.9±0.3 (5‒8) eggs at Hetman NNP, 6.2±0.4 (6‒8) eggs at NPP “Gomilshansky Forests” and 8.5±0.5 (8‒9) eggs at RLP “Feldman Ecopark”. Incubation period of Ph. phoenicurus lasted on average for 15‒20 days.

The objective of this study was to document characteristics of cavities used for breeding by White-backed Woodpeckers Dendrocopos leucotos in Hungary. Twenty-five nest cavities were examined over a period of ten years (2011–2020). Five different tree species were used. The cavities were excavated at a mean height of 4.6 m and 2.2 m standard deviation and ranged from 2 to 8 m. All cavities found were in the main trunks of trees with trunk diameters ranging between 35–55 cm with a mean of 41.6 cm and 5.6 cm standard deviation. A southerly orientation of cavity entrances prevailed with a mean direction of 189±74 clockwise from north (median 180° IQR = 113°). The results suggest that cavity entrance orientation was non-random.

The Firecrest (Regulus ignicapilla) is a regular, but small-number breeder in spruce and coniferous forests in the mountainous and hilly areas of Hungary, but is found in all parts of the country during migration. Despite this, only sporadic field observation data and ringing results in Western Hungary have been published so far. The aim of this study was to investigate the migration of this species on a national scale. In our work, we processed field observation data collected on the Csanádi-hát and capture-recapture data from three bird ringing stations (Szalonna, Tömörd and Ócsa) from the second half of the 1980s to 2021. We also used archive published field observation data from different parts of Hungary. Our results show that the spring migration of the species in the study areas took place between mid-March and late April – early May, and its timing did not differ significantly between regions. In contrast, the autumn migration was earlier in mountainous areas than in lowland areas. The small numbers and short duration of recaptured birds suggested a rapid migration in both periods. In autumn, we obtained a significant difference between the annual number of birds captured in Tömörd and Szalonna. In both periods, males were caught in greater numbers than females. In southern Hungary, the timing of migration in spring has not changed, but in autumn the species migrated earlier than a few decades ago.

The Algerian Nuthatch (Sitta ledanti) is the emblematic bird species of Kabylia of Babors. It is a medium-sized passerine bird species of the Sittidae family. Jean-Paul Ledant discovered this species in October 1975, on the Babor Mountain. Twelve other forests in North-East Algeria has been discovered as breeding sites. These are the forests of the Babors region, in Kabylia. The Algerian Nuthatch was observed mainly in oak, cedar and pine habitats. It is mainly granivorous in winter and an insectivorous in spring/summer or breeding season, which starts in March and can last until July. The incubation period lasts from 14 to 17 days, with clutches of six eggs. The Algerian Nuthatch is listed as an endangered species by IUCN and is protected by the Algerian laws. However, many threats to the environment, such as tree felling and fires, are threatening the species.

The diet composition of Pharaoh Eagle Owl (Bubo ascalaphus) was investigated in a semiarid area of North-western Algeria. A total of 65 pellets regurgitated by the B. ascalaphus were analysed, 288 food items were composed primarily of mammal remains (4 rodents, 1 bat and insectivore, 93.7%), and 1 bird species (passerine, 6.3%). The most frequent prey among the mammals were rodents (83.3%), which included Mus musculus (59.7%), Meriones shawi (11.1%), Meriones libycus (11.1%) and Jaculus jaculus (1.4%). The rodents were the most important prey items in biomass (91.4%), M. shawi made up to 41.9% of the total biomass. We may conclude that the Pharaoh Eagle Owl relies, in its feeding, very broadly on small mammals, completed by other groups.

Many hypotheses try to explain the evolution and possible relations between obligate and facultative brood parasitism in birds. To explore this, a large number of observations and data are needed. Our understanding based on the observations of facultative parasitic species published in the literature is less clear compared to the obligate parasitic species. This communication is about three cases of facultative interspecific brood parasitism. Two nests of Black-headed Gull (Chroicocephalus ridibundus) parasite by Eurasian Coot (Fulica atra) and one nest of Pied Avocet (Recurvirostra avosetta) parasite by Black-winged Stilt (Himantopus himantopus). These observations are significant as long as interspecific brood parasitism was frequently described in Gruiformes (Rallidae) but has rarely observed within Charadriiformes.

Birds with major physical abnormalities do not live for extended periods and, therefore, are rarely observed in the wild. This is particularly the case for birds with defects in their feeding apparatus that succumb to mortality rapidly through precipitous declines in their foraging efficiency and body condition. Sublingual oral fistulas are such an abnormality and involve the development of an opening (or fistula) in the floor of the oral cavity through which the tongue extends, resulting in its permanent exclusion from the mouth. The tongue dehydrates and dies. First described in the 2000s in Stitchbirds (Notiomystis cincta) in New Zealand, it has rarely been reported in other species. However, following our recent discovery of two seabird species on Ascension Island in the South Atlantic displaying oral fistulas, in 2016 I launched a citizen science research project requesting reports of birds with the condition in the world’s avifauna. To date, I have received 188 reports of birds of 82 different species with many contributed from western Europe. However, with only one report from central and eastern Europe, I am now requesting the assistance of birders in the region and in other parts of the world to contribute to this ongoing research project.