Гнездование колпицы (Platalea leucorodia) на Утлюкском лимане (Запорожская область)

Organochlorine contamination in bird's eggs from the Danube Delta

Dynamics of the aquatic nesting bird populations in the mixed colonies from Vulpaşu, Chiriloaia and Cucova (Balta Mică a Brăilei Nature Park, Romania) This study presents the observations made during a three-year period of time (2007-2009) in the three mixed colonies of the Balta Mică a Brăilei Nature Park: Vulpaşu, Chiriloaia and Cucova. In the colonies, there was reported a number of ten aquatic nesting species, with specific differences for each colony separately. The 10 species are: Phalacrocorax carbo (Great Cormorant), Phalacrocorax pygmaeus (Pygmy Cormorant), Nycticorax nycticorax (Night Heron), Ardeola ralloides (Squacco Heron), Egretta garzetta (Little Egret), Egretta alba (Great White Egret), Bubulcus ibis (Cattle Egret), Ardea cinerea (Grey Heron), Plegadis falcinellus (Glossy Ibis) and Platalea leucorodia (Spoonbill). The presence or absence of certain species in a colony is closely related to its ecological requirements, with the structural features of the ecosystems and the climatic conditions.

Data from two projects carried out within the extensive (180 km2) reed belt of Lake Neusiedl, Austria – one about the fish community and the other about the colonial breeding piscivorous birds, great white egret, Casmerodius albus L., purple heron, Ardea purpurea L., grey heron, Ardea cinerea L., and spoonbill, Platalea leucorodia L. – were used to assess the impact of fish-eating birds on the fish population. Piscivorous birds ate about 12% of total fish standing stock within the reed belt. Their food intake was estimated to account for 21% of fish production within a size range of 3–25 cm total length (potential prey size). Competition between fish-eating birds and commercial fisheries was considered to be negligible.

-Habitat use by ardeids in Starling Inlet, Hong Kong, was assessed by walking a fixed 6 km route, two or three times a month, during low tide between August 1997 and August 1998. A total of 36 surveys were made, with a mean count of 452 individuals per survey (S.E. ? 128). Eight species of ardeids and two species of bitterns were recorded. In the winter, non-breeding season, the dominant species was the Great Egret (Casmerodius albus), while in the summer (breeding season) it was the Black-crowned Night Heron (Nycticorax nycticorax). Shallow coastal waters and mudflats were the most important habitats at low tide for Great and Little Egrets (Egretta garzetta), and Grey Herons (Ardea cinerea), while fishponds were the most important for Black-crowned Night Herons. A freshwater marsh was used mainly by Cattle Egrets (Bubulcus ibis) and Intermediate Egrets (Mesophoyx intermedia). During the 1998 breeding season, a comparison was made between the census and a flight-line methods in evaluating ardeid habitat use. Both methods gave similar results for habitat use by Great and Little Egrets, but the census method underestimated the use of mangrove habitats by Black-crowned Night Herons and missed the use of wet grassland habitats outside the inlet by Cattle Egrets. We suggest that the census method is more efficient for assessing the use of particular open habitats, while the flight-line method is more accurate for investigating overall use of a landscape during the breeding season. Received 2 August 2000, accepted 30 December 2000.

As a result of the analysis of the composition and abundance of colonial species of the floodplain ecological and faunal grouping (Phalacrocorax pygmeus, Nycticorax nycticorax, Ardea cinerea, A. purpurea, Ardeola ralloides, Bubulcus ibis, Casmerodius albus, Egretta garzetta, Platalea leucorodia, Plegadis falcinellus) in the lowland Crimea, the features of their distribution on gradients of condition and resource factors were determined. The dynamics of their ecological niches has been revealed depending on the state of nesting and feeding biotopes, the influence of climatic factors and anthropogenic impact. The intensive development of hydro-reclamation, since the 1970s, has led to changes in the hydrological regime of reservoirs, the composition and productivity of the feed resource, and successional changes in vegetation. The composition and productivity of forage biotopes in terrestrial and aquatic ecosystems met the requirements of most species in the 1970s and 1990s. With the optimal state of the factors-conditions and factors-resources, there is practically no competition between species. The founders of the colonies are large heron species with a stretched nesting period, dominating the upper tier of vegetation, while small species of Ardeidae and Phalacrocorax pygmeus settle in polyspecies colonies and occupy the middle and lower tier or periphery of settlements, which provides them with protection from feathered predators.

Nine species of herons were followed to their feeding sites from a nesting colony near Beaufort, North Carolina, by airplane. Except for the Cattle Egret, which flew exclusively to fields and dumps, all other species flew mainly to saltmarsh habitat. In addition, habitats were selected in relation to tidal depth and it appears, at least for the Great Egret, that low tide habitats were preferred. Most Great Egrets, White Ibises, Louisiana Herons, and Snowy Egrets flew close to the colony and numbers decreased farther from the colony. The Great Egret, Black-crowned Night Heron, and White Ibis flew farther from the colony at high than at low tide. In addition, the species differed in distance flown from the colony. Great Egrets traveled farther from the colony when they used thermals. Rate of travel to feeding sites, however, was the same whether Great Egrets used thermals or not. Aggressive encounters were observed in the Great Egret, Louisiana Heron, Snowy Egret, and Black-crowned Night Heron. Cattle Egrets and White Ibises followed other individuals to feeding sites and it appeared as though they were using the colony as an information center. The Great Egret is the only species to effectively use eelgrass beds near Beaufort. The Great Egrets use of this habitat was restricted to about 1.5 hours on either side of low tide. We suspect that other shorterlegged species did not use eelgrass regularly because of its depth. (The author did not submit a manuscript for publication)

Capsule In eastern Austria, Great White Egrets used the extensive reed beds of Lake Neusiedl not only as nesting sites, but also as a major foraging area. Aims To investigate habitat and prey utilization in a growing population of Great White Egrets in different periods of the breeding season and in relation to the water level at the foraging sites. Methods During three breeding seasons, we quantified the utilization of feeding areas and prey by means of aerial surveys and observations on the ground. Results Fish of open water areas within the reed beds of Lake Neusiedl is the main type of prey during the breeding season. Variation in habitat utilization was higher within breeding seasons than among years. The number of foraging individuals in fish-dominated habitats increased linearly during the season, corresponding to decreasing water levels. The utilization of amphibian-dominated habitats showed two peaks related to the spawning period and larval development of prey items. Conclusion The availability of fish within the reed beds of Lake Neusiedl is crucial for the largest population of Great White Egrets in western and middle Europe. The recent increase of this population is probably, in part, caused by an increase of fish availability due to local habitat changes.

The present ornithological report for the Camargue covers six years (1995-2000). This time-period was characterized by mild and wet winters (except the winter of 1999-2000 which was very dry but remained mild). The mean temperatures were all higher than those measured previously. Twenty-two new species have been recorded for the first time (their list is given in the introduction of this paper). The following rare species have been observed again : Bluewinged Teal (a ringed bird in Québec/Canada shows the wild origin of at least one of the three birds seen), Lesser Scaup, Ring-necked Duck, Eastern Imperial Eagle, Lanner Falcon, Saker Falcon, Purple Swamp-hen, Great Bustard, Black-winged Pratincole, Great Sand Plover, Sociable Lapwing, Purple Sandpiper, Buff-breasted Sandpiper, Wilson’s Phalarope, Audouin’s Gull, Arctic Tern, Common Guillemot, Blue-cheeked Bea-eater, Horned Lark, Richard’s Pipit, Blyth’s Pipit, Isabelline Wheatear, Desert Wheatear, Paddyfield Warbler, Marsh Warbler, Barred Warbler, Yellow-browed Warbler, Red-breasted Flycatcher, European Nuthatch, Rosy Starling, Snowfinch, Trumpeter Finch and Lapland Longspur. Among the species or group of species which are regularly censused, two arboreal herons (Little Egret and Cattle Egret) have dramatically increased their numbers ; the 680 pairs of Night Heron and 266 pairs of Squacco Heron in 2000 must be outlined. The Grey Heron stopped its spectacular increase and the Purple Heron continued to fluctuate (1 370 nests in 1996 and 664 nests in 2000). The Greater Flamingo reached the very high figure of 22 200 pairs in 2000 (13 000 in 1996). The breeding gulls and terns in the salines showed some new trends : the Black-headed Gull dramatically decreased (but began to colonize freshwater breeding sites), the Mediterranean Gull reached the very high number of 1 877 pairs in 2000, the Slender-billed Gull maintained its high breeding number (850 pairs in 2000). The four tern species showed the usual fluctuations. The high number of breeding Yellow-legged Gull remained a concern. The salines at Salin-de-Giraud harboured most of the breeding population during this time-period whereas the salines at Aigues-Mortes lost most of their birds. The wintering ducks and coots continued their overall decrease considered as linked to excessive hunting pressure (mostly through disturbance effect of hunting on feeding grounds). The species that have been found breeding for the first time are the Great Cormorant (in 1998), the Great White Egret (first sucessful breeding in 1996), the Eurasian Spoonbill (in 1998), the Eagle Owl (in 2000) and the Pied Wagtail. Among the breeding species, the Collared Pratincole showed a good breeding success in 2000 (42 pairs and 45 fledglings) and several breeding records were found for the Great Spotted Cuckoo. Some species increasingly overwintered : Night Heron, Black Stork, White Stork, Black Kite, Osprey, Common Crane, Stone-curlew, Little Ringed Plover, Common Tern and Pine Bunting.

Avian tuberculosis in naturally infected captive water birds of the Ardeideae and Threskiornithidae families studied by serotyping, IS 901 RFLP typing, and virulence for poultry

Between 1950 and 2016, 254 individuals of Eurasian Spoonbill (Platalea leucorodia) of foreign origin were observed during their dispersal or migration in Hungary from eight countries. Colour-ringed birds originating from Serbia, Croatia and the Czech Republic were the most commonly observed, while individuals from Italy, the Danube Delta (Romania) and the Wadden Sea area (Denmark and The Netherlands) were observed rarely in Hungary. Only metal ringed Spoonbills were recovered from Austria. All age-classes were found in Hungary: juveniles were the most common, while 2cy immatures formed the rarest class. Adults from the Wadden Sea area, and also from the Danube Delta were observed in Hungary during the breeding season, implying potential gene flow between those areas and the Carpathian Basin. My results predict that the breeding population of the Carpathian Basin forms a unique subunit of a metapopulation which is in close contact with the Czech population. The nesting of adults of Serbian and Croatian origin was confirmed in Hungary. Two prospecting subadults (4cy) were observed in Hungarian colonies, one was from Serbia, and the other was from Italy. One adult (5cy) occurred in several Hungarian wetlands in a short period before breeding, which probably explored habitats for breeding or for feeding. Spoonbills of Czech, Serbian, Croatian and Italian origin observed in Hungary used the Central Mediterranean or the Adriatic Flyway. Individuals from the East Atlantic population arrived to Hungary by shifting their migration routes. One bird from the Danube Delta wintered in Tunisia, where it probably joined Hungarian breeders and reached Hungary with them. Adults and juveniles from the Czech Republic used the wetlands around Lake Neusiedler as a stop-over and staging area during autumn migration. My results suggest that Hungarian wetlands play an important role in the movements and breeding of Spoonbills in Central Europe, thus, the management and conservation of these wetlands are essential for the future.

Foraging ecology and diet of Eurasian spoonbills (Platalea leucorodia) in the German Wadden Sea

The number of available publications on the post-fledging parental care of wading birds (herons, ibises, spoonbills, and storks) and many other bird species is limited. In this study, I summarised the available knowledge collated from the observations of the Eurasian Spoonbills (Platalea leucorodia) in Hungary. A part of the available data is based on observations of colour-ringed individuals. The latest feeding event of a young by its parent was observed at Lake Csaj on 5 October 2020. The youngsters were being fed by their parents for 43 days (observed maximum) during the post-fledging dispersal. However, I estimated that this behaviour could even last for as long as 53 days. The parents lead (care for) their yearlings for 51 days (observed maximum), again I estimated that it could potentially last for a longer period of 63 days. The estimated length of parental care and feeding period could be longer or a little bit shorter during the post-fledging dispersal because it was not possible to follow the life of the families exactly. During parental care (feeding and leading of chicks), the majority of the colour-ringed Spoonbills were observed 2–26 km to the natal colonies of yearlings and the breeding colonies of the adults. However, on some occasions, they were 111–145 km far from those colonies. During the post-fledging dispersal, Spoonbills care for their chicks for a longer time than the European breeding heron species. A possible reason could be that the bills of young Spoonbills are not appropriate for fishing effectively at the beginning of fledging because of their shorter length and their less efficient hydrodynamic effect during lateral sweeping. Another reason could be that Spoonbills are tactile foragers and need more time to learn fishing. Based on data of a juvenile followed by a GPS device, learning the migration route and stop-over sites from parents or experienced adults could be important for Spoonbills, otherwise, young migrating alone with no accomplished individuals may not find the optimal routes and the proper stop-over areas. In the case of Spoonbills, we still do not know exactly the features of parental care during the post-fledging dispersal and have even less data on it during the migration. Thus, I request potential observers along the Adriatic Flyway to record the observations of parent-offspring interactions (feeding by parents, begging) particularly the Hungarian colour-ringed adults and/or young individuals and send data to the author’s e-mail address.

Abstract. Studies must be performed throughout the year to determine how the seasonal energy requirements of Snowy Egrets (Egretta thula) and Great Egrets (Ardea alba) change. Foraging behavior was quantified during the breeding season in Kansas and during the non-breeding season in Florida using energetic algorithms and scan sampling. Fifty-eight percent (n = 287) of breeding Snowy Egrets were observed ambulating while 51% (n = 271) of non-breeding Snowy Egrets were observed loafing. Standing foraging was the most commonly observed behavior among Great Egrets in both the breeding (54%, n = 91) and non-breeding (38%, n = 164) seasons. Behavior was dependent on season for both Snowy Egrets (χ2 = 200.1, P < 0.001) and Great Egrets (χ2 = 187.4, P < 0.001). During the breeding season, Snowy Egrets expended 0.13 ± 0.06 W (Watts) in rivers and 0.08 + 0.02 W at weirs. During the non-breeding season Snowy Egrets expended 0.06 ± 0.01 W. During the breeding season Great Egrets expended 0.11 + 0.02 W at both weirs a...

The feeding habitats of Great (Ardea alba) and Snowy (Egretta thula) egrets at the Great Marsh in Northeastern Massachusetts, USA, were characterized through field observations over two years during the breeding seasons of 2012 and 2013. Both species were from a large breeding colony making a daily commute to the Great Marsh for foraging. Habitats at the Great Marsh were delineated as marsh pools, the vegetated marsh, impoundments, open water, tidal flats, and tidal creeks and ditches. Observations (45 counts in 2012 and 48 in 2013) consisted of recording the number of birds, behavior (feeding or not), habitat, and the time of observation and relating these observations to the tidal cycle. The preferred feeding habitats of Snowy Egrets were in marsh pools and along the edges of large impoundments. The preferred feeding habitats of Great Egrets were on the marsh platform, particularly at high tides, and marsh pools. An analysis of physical characteristics with locations of feeding sites revealed no consistent patterns. Certain sites would occasionally support large numbers of feeding Great and Snowy egrets one day only to be ignored the next day at the same tide. The results suggest that Great and Snowy egrets are opportunistic in their selection of feeding sites at the Great Marsh. A future of wetter marshes might provide more feeding opportunities for Great and Snowy egrets, at least in the short-term.

Feeding Snowy (Egretta thula) and Great (Casmerodius albus) egrets were observed during two breeding seasons in coastal New Jersey and two brief winter periods in northeast Florida. A number of tests based on assumptions of foraging models, predictions from foraging theory, and earlier empirical tests concerning time allocation and movement in foraging patches was made. Few of the expectations based on foraging theory and/or assumptions were supported by the empirical evidence. Snowy Egrets fed with greater intensity and efficiency during the breeding season (when young were being fed) than during winter. They also showed some tendency to leave patches when their capture rate declined, and they spent more time foraging in patches when other birds were present nearby. Great Egrets, in Contrast, showed few of these tendencies, although they did leave patches when their intercapture intervals increased. Satiation differences had some influence on feeding rates in Snowy Egrets, but only at the end of feeding bouts. Some individuals of both species revisited areas in patches that had recently been exploited, and success rates were usually higher after the second visit. Apparently, for predators of active prey, short—term changes in resource availability (resource depression) may be more important than resource depletion, a common assumption in most OFT models.