Artificial Nests Research Articles

Status of the Saker Falcon in Hungary between 1980 and 2022

There is limited data available about the status of the Saker Falcon (Falco cherrug) in Hungary before 1980. According to available sources, the species was a regular breeder in several habitat types, but was not common in the late 19th and early 20th centuries. The population decreased significantly through the 20th century falling to fewer than 50 pairs after World War II. The main reasons for the population decrease were DDT and widespread persecution (poisoning and shooting) of raptors by hunters. The species had reached the brink of extinction in Hungary by the 1970s. The Hungarian population of Saker Falcon is closely monitored and protected by MME BirdLife Hungary and the Hungarian National Park directorates’ ranger service over the last forty years. In the framework of Hungary’s national Saker Falcon conservation program, several significant actions have been undertaken: all potential breeding sites were surveyed, nest began to be formally guarded, artificial nests were installed on trees and high-voltage electric pylons, dangerous medium-voltage poles have been retrofitted with bird-friendly designs, and European Ground Squirrels (Spermophilus citellus) have been translocated to their former habitats. In addition, research activities including banding, GPStracking, and prey analyses have begun. The conservation program received significant support from WWF (1986–1990), the European Union’s LIFE Nature program (2016–2018), and the Hungarian government. Thanks to these varied and widespread efforts, the population started to increase slowly, but continuously between 1980 and 2010, with an average population growth rate was approximately 11% annually. The number of known nesting pairs has increased from eight pairs (1980) to 172 pairs (2010). Later population abundance showed fluctuating trends between 2011 and 2022, but remained more or less stable (143–185 pairs). The Hungarian population of Saker Falcons is estimated to be 180–200 nesting pairs. In 2022, 175 nesting pair were documented and 444 chicks fledged from 152 successful breeding attempts. A new EU funded “LIFE SakerRoads” project was launched in 2023 to increase the species’ population on the North-Hungarian Plain, where a significant decline was observed over the last decade.

Bestands- und Brutplatzerfassung von Mehlschwalben (Delichon urbicum, Linnaeus, 1758) und Rauchschwalben (Hirundo rustica, Linnaeus, 1758) im Südwesten und Westen Luxemburgs

Population size, distribution and nesting site characteristics of breeding house martins and barn swallows were investigated in the mixed rural and urban landscape of southwestern and western Luxembourg. House martins were mapped in 34 municipalities (670 km2) between 2013 and 2020 and barn swallows in 11 municipalities (228 km2) between 2017 and 2020, representing nearly a quarter and a tenth of the national surface, respectively. By means of one visit per season, nests as well as their occupation status were recorded in a comprehensive mapping effort comprising settlements as well as farmsteads. For the house martin, 4,109 nests were mapped, 1,025 of which were occupied and distributed over 368 colonies with an average number of 2.78 breeding pairs per colony and a population density of 1.62 breeding pairs per km2. Nearly one third of the recorded martin pairs were settled in artificial nests, underlining the effectiveness of this conservation measure. Barn swallow nests numbered 1,395, of which 655 housed breeding pairs, distributed over 107 sites with an average colony size of 6.12 breeding pairs and a population density of 2.89 breeding pairs per km2. Between-year occupancy rates as well as abundances varied strongly between different municipalities in the study area in both species. Generally low breeding densities reflect the unfavourable conservation status for both red-listed swallow species.

The effects of anthropogenic noise on nest predation with respect to predator species across different habitats and seasons

Noise pollution is a major component of sensory pollution that can disrupt the well-being and functioning of living organisms, affect a variety of life history traits in animals, and reduce their reproductive success. In this study, we used artificial nest experiments with noise manipulation to investigate the influence of anthropogenic noise on nest predation during the breeding and non-breeding seasons and in different forest habitats. We found that the noise treatment did not alter the predation rates or survival probabilities of birds in artificial nests. However, the diversity and species composition of nest predators in artificial pine forests varied between breeding and non-breeding seasons, which may be explained by season-specific adaption of nest predators to bird nests or the unstable ecosystems of artificial forests. The diversity and species composition of nest predators differed between the different forests, probably because of differences in habitat heterogeneity. Predation time varied with treatment, season, and habitat, although most predators were nocturnal mammals. Niche segregation or changes in optimal foraging time may explain this phenomenon.

Степной орёл в Алтае-Саянском регионе – результаты исследований 2019–2023 годов

Степной орёл в Алтае-Саянском регионе – результаты исследований 2019–2023 годов

Evolution of fish community structure, cause analysis and implications for <i>ex-situ</i> conservation of Yangtze finless porpoise in Tian-e-Zhou Oxbow of Yangtze River

长江天鹅洲故道是长江江豚首个迁地保护区，其中充足而适口的饵料鱼类资源是长江江豚种群健康发展的保障。为此，根据2017年10月-2021年4月对长江天鹅洲故道进行的7次鱼类调查数据，结合禁捕前的历史数据，对其鱼类群落结构演变进行了分析，并针对长江江豚饵料鱼的供应状况对天鹅洲故道内鱼类资源管理提出了建议。调查期间，共采集到鱼类57种，其中，蒙古鲌（Culter mongolicus）、鲢（Hypophthalmichthys molitrix）和鳙（Aristichthys nobilis）等大中型鱼类生物量明显增加，而䱗（Hemiculter leucisculus）和似鳊（Pseudobrama simoni）等小型鱼类生物量呈现下降趋势。鱼类群落优势种逐渐由太湖新银鱼（Neosalanx taihuensis）、短颌鲚（Coilia brachygnathus）和䱗等小型鱼类转变为鳙、蒙古鲌和拟尖头鲌（Culter oxycephaloides）等大中型鱼类，尤其是新近出现的拟尖头鲌种群发展迅速。同时，短颌鲚和䱗等小型鱼类的体重在减小，而鲢、鳙等大中型鱼类规格在持续提高。长江江豚以小型鱼类和大中型鱼类的幼鱼为食，其资源下降将威胁长江江豚种群的维持和发展。为保障天鹅洲故道内长江江豚的食物供应，建议适当地捕捞鲢、鳙、蒙古鲌和拟尖头鲌，减缓鲢、鳙对小型鱼类的食物竞争压力，以及降低蒙古鲌和拟尖头鲌对小型鱼类的捕食压力；同时丰水期加强故道与长江的连通，引入更多长江干流繁殖的小型鱼类资源；并通过建设人工鱼巢以改善故道内䱗等产粘性卵小型鱼类的繁殖条件，增加小型鱼类资源量。;Tian-e-Zhou Oxbow is the first habitats for the ex-situ reserve established for the Yangtze finless porpoise. The rich and abundant forage fish resources are the guarantee for the healthy development of the Yangtze finless porpoise population. Therefore, the change of fish community structure was analyzed with combined of seven fish surveys data in Tian-e-Zhou Oxbow of Yangtze River from October 2017 to April 2021 and historical data before the fishing ban. In view of forage fish of Yangtze finless porpoise, some suggestions were provided for the scientific management of fish resources in Tian-e-Zhou Oxbow. During the investigation, 57 fish species were collected. The biomass of large and medium-sized fish such as Culter mongolicus, silver carp and bighead carp increased significantly while the biomass of small-sized fish such as Hemiculter leucisculus and Pseudobrama Simoni showed a declining trend. The dominant fish species gradually changed from small-sized fish such as Neosalanx taihuensis, Coilia brachygnathus and Hemiculter leucisculus to large and medium-sized fish such as bighead carp, Culter mongolicus and Culter oxycephaloides, in particular, the newly emerged Culter oxycephaloides population developed rapidly. Meanwhile, the body-weight of small-sized fish such as Coilia brachygnathus and Hemiculter leucisculus was decreasing, but the body-weight of large and medium-sized fish was increasing. Because the Yangtze finless porpoise feeds on the small-sized fishes and juveniles of large and medium-sized fishes, the decline of their food resources would threaten the maintenance and growth of the Yangtze finless porpoise population. In order to ensure food supply for the Yangtze finless porpoises in Tian-e-Zhou Oxbow, it suggested that rational capture of silver carp, bighead carp, Culter mongolicus and Culter oxycephaloides should be taken into consideration in order to reduce the food competition pressure of silver carp and bighead carp and the predation pressure of Culter mongolicus and Culter oxycephaloides on small-sized fishes. Besides, another measures to increase the small-sized fish resources like strengthening the connectivity of the oxbow with Yangtze River in the wet season to introduce more small-sized fish resources from Yangtze River and laying artificial fish nests in the oxbow to improve the breeding conditions for the small-sized fish species with adhesive eggs such as sharply should be carried out.

Flexible nest site selection of the endangered Oriental Storks (Ciconia boyciana): Trade-off from adaptive strategies

Nest site selection is a vital component of bird reproduction success, and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances. Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications. In this study, we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks (Ciconia boyciana) in different nest areas. Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas, and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas. The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks. The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain; however, nest height decreased with the abundance of food resources in the Northeast China nest area. Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies. In safer environments, nests were lower and closer to food resources, which allows parent storks to invest more in the nestlings. However, in areas where human activity was intense, nests were higher to ensure the safety of their offspring. Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting. Finally, the establishment of soft barriers around the nesting areas could increase the safety of nests.

Distribution, Population Status, Ecology, and Conservation of Eastern Imperial Eagle in Thrace Ecoregion (Bulgaria and Turkey)

The Thrace geographical region comprises territories of three states and covers an area of about 70,000 km2. At the end of the 19th century, the Eastern Imperial Eagle (Aquila heliaca) was widespread throughout the region, occupying a variety of habitats. The mid-20th century marked the beginning of its dramatic decline, and in the latter half of the century the birds breeding in Northern Thrace amounted to 15–20 pairs, Eastern Thrace harbored scattered pairs along the lower reaches of the Maritsa River, while in Western Thrace the population was estimated at 6–10 pairs only. Since 2005, the intensive conservation activities implemented in Bulgaria have improved the status of the Eastern Imperial Eagle in Northern Thrace. At the same time, in Western Thrace (the Greece), only one pair was confirmed in Dadia National Park. Since 2008, intensive field research in European Turkey identified an abundant and stable population of the species. 63 different breeding territories were established in Bulgaria, while in European Turkey the number of identified breeding territories was 64. Most of the pairs were distributed in the European Green Belt area, along the former Iron Curtain, where human access had been strictly limited, thus preserving extremely rich biodiversity. Based on a long-term population survey of this species in Bulgaria and European Turkey, we estimated this subpopulation of the species at about 110–120 breeding pairs. Breeding of several pairs in Greece, in the Greece-Turkey border area, along the Evros River, is also possible. The Thracian sub-population of the Eastern Imperial Eagle is gradually increasing. The main threats are electrocution, poisoning, habitat destruction, shooting, disturbance, and food depletion. In Bulgaria the main conservation actions include: insulation of hazardous electric poles, purchase of land plots and their subsequent management as pastures, construction of artificial nests, restoration of breeding habitats through Poplar planting, supplementary feeding of pairs during the breeding and the wintering periods, guarding of nests at risk, satellite tracking, implementation of educational programs with children and local communities. Actions are needed to mitigate the limiting factors in European Turkey, as well as to study the status of the species in Northern Greece. International cooperation would guarantee the stability of the Thracian sub-population of the Eastern Imperial Eagle.

Advances in Clinical Toxicology depend on Ecotechnology

The oldest enriched habitat of the Banka-Siphon-Dam (BSD) of Banka River (BR) attached to Eden Canal (EC) of Damodar River (DR), Kanchannagar, Burdwan, West Bengal India, covering a 3-5 sq km area with different flora- and faunal diversity with agricultural fields and dense vegetation forty-five years ago. But it was decreasing gradually up to December 2019 due to massive visitors or tourists, picnic parties with large sound systems, irregular fishing, killing wild animals, cutting the trees, disturbing and catching different animals including migratory birds, unethical human behaviors, and urbanization nearby badly affected on ‘Advances in Clinical Toxicology’. On the other hand, the Covid-lockdowns also impacted the ecosystem health during the pandemic coronavirus-disease (COVID-19), it has also faced social and economic challenges among the communities, and health systems-“the invisible patients”, due to hampering truism and education, and suspicious killing or catch or death of grey-coloured water monitor lizards, fishing cats, civet cats, and barn owls, and even migratory birds also. And has lost the ecological balance of water, land and vegetation (micro bio-climate) with an increased viper snake, rodent population, etc. And adversely affect the environment (Water, Sanitation and Ecology) and societal problems. To overcome, it is therefore, augments and confirms that propagation of the artificial nests, awareness, plantation of different fruits plants, and cultivations would be beneficial to do away with the rodent menace primarily, and inhibit the damage and economic losses, without putting any severe implications on the sustainability of pisciculture-fishery agro-ecosystems of the “Banka-Siphon Eden-Canal of Damodar May be Develop as ‘Biodiversity-Biomedicines-Hub for Advances in Clinical Toxicology Depend on Eco-technology’ Improving World Policy”. And the perfect ecological balance of water, land and vegetation may develop any ‘Future-Socioeconomically-Ecological-Tourist-Hub with Advances in Clinical Toxicology Eco-Technology Hub’

Новые данные по гнездовой биологии, экологии и состоянию популяции орлана-белохвоста в Дагестане, Россия

Новые данные по гнездовой биологии, экологии и состоянию популяции орлана-белохвоста в Дагестане, Россия

What happens to Saker Falcon in Chinese Altai?

In China, the protection level of Saker Falcon (Falco cherrug) has been upgraded from National Level II to National Level I in 2021. Why is this happening? We know there are some reasons for this. Firstly, there has been excessive capture over the past thirty years, including legal or illegal activities focusing on domestic and foreign markets, of course, most of which have been negotiated between governments. The most symbolic event was Qatar's support of 100 million Yuan to establish a Saker Falcon Breeding Center of Altay in 2014. Soon, the relevant departments issued orders and target tasks to capture young falcons in various counties in the Altay region. In addition to capturing a large number of migrating falcons for supply to Qatar and Saudi Arabia, other threats have also quickly emerged in northern Xinjiang. For example, largescale mining, including direct destruction of breeding habitats by open-pit coal mines and quarries, as well as the construction of hundreds of power stations locally for the so-called “from West to East Power Transmission” project. The results are almost complete loss of habitats, frequent electrocutions, collisions, and poisoning. Although relevant departments have also built artificial nests for falcons in other places, the results have been minimal and insufficient to compensate for rapid population loss.

Variation in reproductive life-history traits of Chinese Bulbuls (Pycnonotus sinensis) along the urbanization gradient in Hangzhou, China

Urbanization brings new selection pressures to wildlife living in cities, and changes in the life-history traits of urban species can reflect their responses to such pressures. To date, most of the studies investigating the impacts of urbanization on avian life-history traits are conducted in Europe and North America, while such studies are often lacking in quickly developing countries in Asia (e.g., China). In this study, we examined the variations in reproductive life-history traits of Chinese Bulbuls (Pycnonotus sinensis) along the urbanization gradient in Hangzhou, China. We detected 234 natural nests of Chinese Bulbuls and continuously monitored them in two continuous breeding seasons from 2012 to 2013. We collected data on seven life-history traits (laying date, incubation period, nestling period, clutch size, egg volume, hatching success rate, and fledging success rate). We used infrared cameras to record the number of feedings per hour as the measure of food resources for the nestlings. We measured nest predation pressure by monitoring 148 natural breeding nests during breeding seasons and 54 artificial nests immediately after breeding seasons. We then calculated the urbanization synthetic index (USI) as a measure of the level of urbanization and examined its relationship with the seven life-history traits. We found that Chinese Bulbuls laid eggs significantly earlier with increasing USI. However, the other six life-history traits did not vary significantly with the USI. Moreover, the feeding frequency of chicks increased significantly with the USI, but the nest predation pressure of Chinese Bulbuls decreased significantly with the USI. Increased food resources and reduced nest predation pressure in cities may lead to earlier laying date of Chinese Bulbuls. Further study should test whether the earlier laying date of Chinese Bulbuls is the result of phenotypic plasticity or genetic change.

Ecological factors influencing the breeding performance of great tits (Parus major) in artificial nest boxes

Installing an artificial nest box has a positive effect on the cavity nesters such as great tit (Parus major). Beyond the process of installing an artificial nest box, a study on the effect of ecological factors on breeding performance is necessary. This study was conducted to evaluate the ecological factors influencing breeding performance of great tits (Parus major) in artificial nest boxes in temperate mixed forests. In this study, the first egg-laying date and percentage of shrub were closely related among ecological factors. Variable influencing clutch size was date of first egg-laying date. Percentage of shrub had a positive relation to hatching success and fledgling success. First egg-laying date may represent quality of parental individuals. In addition, shrub can provide better food resources and has an impact on hatching success and fledgling success. These results suggest that higher quality of parental individual predominates the better the foraging site for enhancing breeding success. Also, managing shrubs in the forest appear to have a positive effect on breeding performance. Moreover, long-term ecological research is needed for the conservation of the birds and their habitats.

Vércse költőláda kihelyezések tapasztalatai a Mosoni-Síkon

The Mosoni Plain Natura 2000 site is one of the most western nesting sites of the strictly protected Red-footed Falcon (Falco vespertinus) in Hungary, and the Common Kestrel (Falco tinnunculus) is the most common nesting bird of prey in the area. The breeding success of these two species, which do not build nests, can be greatly enhanced by the installation of good quality and properly placed artificial nests boxes. Monitoring of the artificial nest-boxes was previously not regularly and entirely conducted. However, from 2019 onwards, the now nearly 100 active nest-boxes are being regularly monitored, recording nest occupancy, clutch size and fledging data for Red-footed falcon, Common Kestrel, as well as for the Long-eared owl. The presenent paper summarises the nesting records of these three species on artificial breeding sites on the Moson Plain. During the period 2019–2023, we observed a total of 12 Red-footed Falcon breedings, 7 of which were in artificial nestboxes. On average, 3.0 chicks were successfully fledged from the boxes. Regarding Common Kestrel, a total of 121 breedings were recorded in nesting boxes, of which more than 80% were successful. On average 3.84 chicks fledged per nest box. During the 5 years of the study, a total of 14 pairs of Long-eared Owl breeding were associated with artificial nest-boxes, of which 10 proved successful. A total of 35 chicks fledged successfully.

Breeding status of invasive Rose-ringed Parakeets Psittacula krameri in Durban, South Africa

The Rose-ringed Parakeet Psittacula krameri has established feral populations in South African suburban areas. However, the information on the breeding biology of parakeets remains poorly documented in the country. We assessed parakeets’ breeding status and behaviour by locating their roost and breeding sites in Durban, eThekwini Metropole, KwaZulu-Natal province. We also placed artificial nest boxes to determine the occupancy of parakeets or other bird species. We identified 39 parakeet breeding sites with a total of 72 nests. There were no significant differences between the number of active parakeet nests in the first (n = 53 nests) and second breeding seasons (n = 59). Rose-ringed Parakeets used four tree species for nesting, with the white milkwood Sideroxylon inerme used the most (71%). Only East African lowland honey bees Apis mellifera scutellata and Common Mynas Acridotheres tristis used the artificial nest boxes. Parakeet fledgings recorded ranged between one and three per nest, and their numbers differed significantly between seasons. The number of fledglings was not influenced by any of the tree variables measured and distance or location. The distance between the parakeets’ roosting and breeding sites ranged from 1.43 to 5.0 km. Our study provides essential data for an overall management strategy, including eradication programs for this species in South Africa.

To the ecology and biology of closely related species of thrushes of the genus Turdus in different landscapes of northeastern Ukraine

Systematic observations of the avifauna of the Pine park in in the city Lohvytsia, the outskirts of the village Potoky and in the «Vakalivshchyna» tract allow to conclude that song thrushes and blackbirds are quite numerous birds, due to the large number of biotopes suitable for their nesting. 37 cases of nesting of Turdus merula and 30 cases of Turdus philomelos were noted. The nesting density of the song thrush in the Pine park of Lokhvytsia is set at 0,36 pairs/km2. In the vicinity of the village The flow rate was 0,96 pairs/km2, in the Vakalivshchyna tract it was 2,5 pairs/km2. For the blackbird, the nesting density in Pine park was 0,36 pairs/km2, the vicinity of the village Potoky – 0,46 pairs/km2 and in oak tracts – 1,5 pairs/km2. In various landscapes of northeastern Ukraine, the nesting period of songbirds and blackbirds extends from April to June. In the Poltava region, the singing thrush arrives days earlier than in the Sumy region. We tend to believe that this is related to the adaptation of the species to the environment in the conditions of urban tree plantations. In different landscapes of the north-east of Ukraine, the construction of nests by Turdus philomelos begins in the first ten days of April (04.01−10.04) at the daytime temperature of +8.5±1.5 °C. Turdus merula builds nests in the first ten days of April (01.04−10.04) in various landscapes of the north-east of Ukraine at an average daily temperature of +5.0±1.0 °С. When different species of blackbirds live together (in the same conditions), species-specific features are most clearly manifested in the distribution of nests by species of trees and bushes, the nature of the location of nests and the height of their placement. The list of species of trees and bushes on which nests of Turdus philomelos and Turdus merula are placed includes 8 plant species. Turdus philomelos prefers nesting sites for Acer negundo (66.6%) in the vicinity of the village Potoky, Ulmus minor (55.5%) and Acer negundo (44.5%) in the Pine Park, Quercus robur (50%) and Ulmus minor (50%) in the Vakalivshchyna tract. Both types of blackbirds are characterized by individual variability in the choice of nest locations. This is most clearly manifested in the atypical location of the nests in the artificial nests (without the top cover and front wall).

Methods and Techniques for Making Artificial Nests for Eagle-Owls (Bubo bubo, Strigiformes, Strigidae) to Increase Their Population

Methods and Techniques for Making Artificial Nests for Eagle-Owls (Bubo bubo, Strigiformes, Strigidae) to Increase Their Population

TRUNK SIZE INFLUENCES SPECIES RICHNESS AND FUNCTIONAL COMPOSITION OF BIOGEOGRAPHICALLY DIFFERENT TREE-VISITING ANT COMMUNITIES IN PEAR ORCHARDS

We investigated the diversity of ant assemblages visiting pear trees in Italy by comparing two orchards from a northern region with continental climate (Emilia-Romagna) and a southern region with Mediterranean climate (Sicily). Overall we identified 20 ant species belonging to 10 genera and 3 subfamilies. The ant communities of the two sites look significantly different in biogeographic terms, but their functional composition is similar. Moreover, we discovered that both ground and arboreal nesting species richness is positively correlated with the trunk circumference. In particular, arboreal-nesting species are limited to the deadwood richer medium and large trees. Some of the detected ant species may be useful to pest control strategies, and artificial nests may be considered to attract arboreal-nesting species in deadwood-poor trees. Key Words: arboreal ants, myrmecology, Sicily, Emilia Romagna.

Nesting Biology and Ecology of a Resin Bee, Megachile cephalotes (Megachilidae: Hymenoptera).

We report the nesting biology and ecology of Megachile cephalotes Smith, 1853 for the first time in Pakistan. Wooden and bamboo trap nests were deployed at three different locations in Bahawalpur district, Pakistan, from January 2020 to May 2021. A total of 242 nests of M. cephalotes were occupied in all three locations with the maximum abundance in the Cholistan Institute of Desert Studies. Megachile cephalotes remained active from March to September (the spring and summer seasons). In a nest, females made 7-8 brood cells each having a length of 1.2-2.3 cm. Plant resin was used to construct cells and mud or animal dung to plug the nest entrance. A vestibular cell was also made between the outermost brood cell and the nest entrance that ranged from 1.4 to 2.5 cm in length. No intercalary cells were observed in the nests. The males took 65.3 days to become adults, while the females took 74.78 days. The sex ratio was significantly biased toward females in all three locations. Grewia asiatica was the predominant pollen grain species found in the brood cells. Megachile cephalotes were observed collecting resin from Acacia nilotica, Prosopis juliflora, and Moringa oleifera. Three cleptoparasites of this species were also recorded: Euaspis carbonaria, Coelioxys sp., and Anthrax sp. This study set up a background to encourage new studies on artificial nesting and provides tools for proper biodiversity management and conservation.

Nest Architecture, Prey, and Body Size in the Grass-Carrying Wasp, Isodontia auripes, at two sites in New York (Hymenoptera: Sphecidae)

Isodontia auripes [Fernald] females nested in fourteen 12-mm diameter artificial trap nests at two locations in New York State (Geneseo and Rensselaerville). We report broods of up to 14 pupae in a single chamber with an average of 5.8 pupae per chamber (previously reported range 2 - 6 pupae/chamber). Nest architecture, with plugs of finely shredded, packed grass and coarse, wound grass stems, was similar to other reports of I. auripes nests, except that only one nest contained a grass partition on the back wall of the chamber (in a case where mud-nesting wasps had preceded I. auripes). All prey items that could be identified to species were either the non-native drumming katydid, Meconema thalassinum [DeGeer], or the narrow-winged tree cricket, Oecanthus niveus [DeGeer]; M. thalassinum accounted for 71% of identified prey and is a new prey record for this wasp. Nests contained an estimated average of 11 prey per pupa, with a strongly female-biased prey sex ratio. The 116 collected pupae suffered from high pre-emergence mortality (65.5%), mostly due to the presence of parasitic flies and chalcid wasps in many nests. Adult females were larger than males in body mass and head width but did not differ in emergence time. Both male and female wasps could be found within single brood chambers, though the population was male-biased (2.4:1) and individual nests strongly favored one sex. In general, pupal cases closest to the nest entrance within a chamber were smaller than those found furthest away, suggesting size-related fitness impacts for offspring based on the order of egg laying.

Mink predation in great crested grebe colonies: random robbery or a well-planned hunt?

The study aimed to recognize whether the activity of a semi-aquatic invasive carnivore – the American mink Neovison vison – is related to the distribution of waterbird colonies. For this reason, we monitored mink occurrence in lake reedbeds and the fate of artificial nests imitating those of the great crested grebe Podiceps cristatus. The location of artificial nests in the grebe colony increased the probability of their survival compared to those placed outside the grebe colony. During the study, mink activity increased over time. In general, it was lower in colonies than outside of them, suggesting that the presence of natural nests does not increase the probability of mink occurrence in lake reedbeds. However, mink activity was negatively correlated with the distance from the lake shoreline and differed spatially according to the presence or absence of natural grebe nests. In grebe colonies, the probability of mink occurrence at greater distances from the lake shoreline was higher than outside, which can be explained by optimizing swimming effort while searching for prey. In conclusion, mink activity in colonies was lower than in areas with no waterbird nests, and nest location in a colony decreased predation risk by mink.