First record of a possibly overlooked impact by alien parrots on a bat (Nyctalus leisleri)

The role of the pineal gland and its hormone melatonin in the regulation of annual testicular events was investigated for the first time in a psittacine bird, the roseringed parakeet (Psittacula krameri). Accordingly, the testicular responsiveness of the birds was evaluated following surgical pinealectomy with or without the exogenous administration of melatonin and the experimental manipulations of the endogenous levels of melatonin through exposing the birds to continuous illumination. An identical schedule was followed during the four reproductive phases, each characterizing a distinct testicular status in the annual cycle, namely, the phases of gametogenic quiescence (preparatory phase), seasonal recovery of gametogenesis (progressive phase), seasonal initiation of sperm formation (pre‐breeding phase), and peak gametogenic activity (breeding phase). In each reproductive phase, the birds were subjected to various experimental conditions, and the effects were studied comparing the testicular conditions in the respective control birds. The study included germ cell profiles of the seminiferous tubules, the activities of steroidogenic enzymes 17β‐hydroxysteroid dehydrogenase (17β‐HSD), and Δ53β‐hydroxysteroid dehydrogenase (Δ53β‐ HSD) in the testis, and the serum levels of testosterone and melatonin. An analysis of the data reveals that the pineal gland and its hormone melatonin may play an inhibitory role in the development of the testis until the attainment of the seasonal peak in the annual reproductive cycle. However, in all probability, the termination of the seasonal activity of the testis or the initiation of testicular regression in the annual reproductive cycle appears to be the function of the pineal gland, but not of melatonin.

Biological invasions pose a significant threat to biodiversity, yet the severity and direction of impacts differs between taxa. The non-native evergreen shrub Rhododendron ponticum has colonized large areas of woodland understorey in the UK and is currently undergoing widespread clearance due to its negative impacts on native flora and as a potential host reservoir for harmful pathogens. Presence of rhododendron significantly increases the amount of structural clutter in the understorey and, hence, modifies microhabitat structure, which might have an impact on bat foraging activity. Here, for the first time, we investigated the effects of rhododendron on activity of British bat species by performing autonomous acoustic surveys at twelve sites in Richmond Park, London, where rhododendron was either present, absent or recently removed. The effects of other microhabitat characteristics likely to influence bat activity (e.g. tree diversity, canopy cover, distance to water and the presence/absence of deer) were also considered. We predicted that the increased understorey clutter present in areas invaded by rhododendron would reduce the activity of larger, less agile bats Nyctalus noctula, Eptesicus serotinus and Nyctalus leisleri (NSL), whereas the activity of bat species able to forage within, or at the edges of, clutter (e.g. Myotis spp. and Pipistrellus spp.) would not be negatively affected. While our results indicated a significant reduction in the activity of larger, open space foragers (NSL) in rhododendron-invaded areas, deer presence had a stronger negative effect than woody understory density and canopy cover on these bat species. Activity of other bats recorded was not negatively impacted by the presence of rhododendron. However, sites where rhododendron had been removed demonstrated higher bat activity levels than sites where rhododendron was present and absent with the exception of Pipistrellus pygmaeus, which displayed higher activity levels in the presence of woody understorey. NSL and P. pipistrellus also demonstrated more frequent commuting/roosting activity in sites without rhododendron, although P. pygmaeus and Myotis spp. appeared to be regularly utilising at least some rhododendron sites for this purpose. To mitigate potential negative effects of rhododendron removal on some bat species, we therefore suggest restriction of deer access to sites to enable recovery of native woody understorey.

A complete list of bat records available from Northern Cyprus is presented, based on both limited literature and new records, resulting from a recent field survey conducted mainly in 2018. This review is complemented by distribution maps and summaries of the distributional status of particular species. From the northern part of the island of Cyprus, at least 451 records of 21 bat species are available; viz. Rousettus aegyptiacus (26 record localities), Rhinolophus ferrumequinum (19), R. hipposideros (21), R. euryale (5), R. mehelyi (1), R. blasii (12), Myotis blythii (4), M. nattereri (10), M. emarginatus (3), M. capaccinii (1), Eptesicus serotinus (5), E. anatolicus (1), Hypsugo savii (6), Pipistrellus pipistrellus (50), P. pygmaeus (9), P. kuhlii (265), Nyctalus leisleri (1), N. lasiopterus (1), Plecotus kolombatovici (3), Miniopterus schreibersii (4), and Tadarida teniotis (5). The number of records increased elevenfold and 1.5 times more bat species were found compared to the last review published in 2007. Seven bat species (Rhinolophus euryale, Myotis emarginatus, Pipistrellus pipistrellus, P. pygmaeus, Nyctalus leisleri, N. lasiopterus, and Miniopterus schreibersii) are reported from Northern Cyprus for the first time; also, R. euryale is confirmed for the first time from the whole island. With the exception of Nyctalus noctula, for which doubtful records exist only from Southern Cyprus, the complete known bat fauna of the island was documented in Northern Cyprus. Moreover, three bat species, Rhinolopus mehelyi, Myotis capaccinii and Eptesicus anatolicus, were reported only from the northern part of Cyprus, although the record of M. capaccinii is considered as problematic and the occurrence of this species on the island is unlikely. For the first time, a population trend in a bat population is reported in Cyprus; smaller colonies of Rousettus aegyptiacus, even abandonment of roosts, were observed during the recent survey compared to numbers recorded in the mid-2000s.

The effect of logging on fission-fusion behaviour of tree-dwelling bats explored by an agent-based model

The gastrointestinal tract of animals is adapted to their primary source of food to optimize resource use and energy intake. Temperate bat species mainly feed on arthropods. These contain the energy-rich carbohydrate chitin, which is indigestible for the endogenous enzymes of a typical mammalian gastrointestinal tract. However, the gastrointestinal tract of bat species should be adapted to their diet and be able to digest chitin. We hypothesized that (i) European vespertilionid bat species have the digestive enzyme chitinase and that (ii) the chitinolytic activity is located in the intestine, as has been found for North American bat species. The gastrointestinal tracts of seven bat species (Pipistrellus pipistrellus, Plecotus auritus, Myotis bechsteinii, Myotis nattereri, Myotis daubentonii, Myotis myotis, and Nyctalus leisleri) were tested for chitinolytic activity by diffusion assay. Gastrointestinal tracts of P. pipistrellus, P. auritus, M. nattereri, M. myotis, and N. leisleri were examined for acidic mammalian chitinase by western blot analysis. Tissue sections of the gastrointestinal tract of P. pipistrellus were immunohistochemically analyzed to locate the acidic mammalian chitinase. Chitinolytic activity was detected in the stomachs of all bat species. Western blot analysis confirmed the acidic mammalian chitinase in stomach samples. Immunohistochemistry of the P. pipistrellus gastrointestinal tract indicated that acidic mammalian chitinase is located in the stomach chief cells at the base of the gastric glands. In conclusion, European vespertilionid bat species have acidic mammalian chitinase that is produced in the gastric glands of the stomach. Therefore, the gastrointestinal tracts of insectivorous bat species evolved an enzymatic adaptation to their diet.

The eastern gray squirrel (Sciurus carolinensis) has been labeled as one of the 100 worst invasive alien species by the IUCN. In Europe, the species has been introduced to Britain, Ireland and Italy, and its subsequent spread has resulted in wide-scale extinction of native Eurasian red squirrels (Sciurus vulgaris) from the areas colonized by the gray squirrel. This replacement of a native by an alien competitor is one of the best documented cases of the devastating effects of biological invasions on native fauna. To understand how this replacement occurs, we present a systematic review of the literature on competition and interactions between red and gray squirrels. We describe the patterns of red and gray squirrel distribution in those parts of Europe where gray squirrels occur and summarize the evidence on the different processes and mechanisms determining the outcome of competition between the native and alien species including the influence of predators and pathogens. Some of the drivers behind the demise of the red squirrel have been intensively studied and documented in the past 30 years, but recent field studies and mathematical models revealed that the mechanisms underlying the red-gray paradigm are more complex than previously thought and affected by landscape-level processes. Therefore, we consider habitat type and multi-species interactions, including host-parasite and predator-prey relationships, to determine the outcome of the interaction between the two species and to better address gray squirrel control efforts.

Background: Alien species are one of the major causes contributing to biodiversity loss. In Europe, over 340 alien bird species have been recorded in the wild, of which 74 are established. Among 12 established alien parrot species in Europe, the Rose-ringed Parakeet (RRP) Psittacula krameri is the most abundant and widespread. Objective: Although one of the best documented alien vertebrates in Europe, historical and current datasets on RRP invasion success and demography have not been systematically collated and analysed. This paper therefore aims to bring together, verify and make available this information. Method: Existing distribution and demographic data for the RRP in Europe were collated from the following sources: (a) literature search; (b) bird sighting databases; (c) regional bird experts; (d) RRP roost counts. With this data, we evaluated population size and growth per population, country and the whole of Europe in the period 1965-2015. Results: The RRP is well established in Europe with at least 90 breeding populations in 10 countries, and a total population size of at least 85,000 birds as of 2015. For Western Europe, long-term demographic data indicate the species has grown considerably in number, although some populations have failed to persist. Data is scarce for countries in Central, Eastern and Northern Europe. Conclusion: Our synthesis reveals a positive demographic trend across Europe, although locally, some populations appear to have reached carrying capacity. Further research is needed to understand the mechanisms underlying RRP population growth in Europe, and methods amenable to citizen-scientists are urgently required to monitor population and range dynamics.

In this report, we have examined the effects of lithium on testicular morphology in a male subtropical wild avian species, the roseringed parakeet (Psittacula krameri). Adult male birds were collected during the months of February-March, a time when the testicular gametogenic activity in these seasonally breeding birds is at its peak. They were injected, intramuscularly, twice daily (07:00 and 19:00 h) with lithium chloride (Sigma Chemical Company) at a dosage of 0.5 mEq/Kg body weight either for 5 or 10 days. A significant decrease in both the absolute and relative testicular weights was evident in the lithium-treated birds as compared to those of the saline-injected control animals. Light microscopic studies of the testis in the lithium-treated animals showed a wide range of degenerative changes. These included a) a significant reduction in the diameter of seminiferous tubules; b) necrosis and exfoliation of most of the germ cells in the seminiferous tubular lumen with the exception of the spermatogonia; and c) a significant reduction in the number of mature spermatozoa in the tubular lumen. These degenerative changes were dependent on the duration of lithium treatment and were evident when the plasma lithium concentrations were well below the human therapeutic range. Leydig cell morphology was not affected by lithium however. Our results provide the first experimental evidence of lithium's adverse reproductive function in an avian species. These data provide further support to the view that lithium adversely affects the male reproductive system and that these effects extend beyond mammalian species.

Certain traits of recipient environments, such as the availability of limiting resources, strongly determine the establishment success and spread of non-native species. These limitations may be overcome through behavioral plasticity, allowing them to exploit alternative resources. Here, we show how a secondary cavity nester bird, the rose-ringed parakeet Psittacula krameri, innovates its nesting behavior as a response to the shortage of tree cavities for nesting in its invasive range in Tenerife (Canary Islands). We observed that some breeding pairs excavated their own nest cavities in palms, thus becoming primary cavity nester, whereas others occupied nests built with wood sticks by another invasive species, the monk parakeet Myiopsitta monachus. The use of these novel nesting strategies increased the number of breeding pairs by up to 52% over 6 years, contributing to a 128.8% increase of the whole population. Innovative nests were located at greater heights above ground and were more aggregated around conspecifics but did not result in greater breeding success than natural cavities. Occupation of monk parakeet colonies by rose-ringed parakeets also benefited the former species through a protective-nesting association against nest predators. Our results show how an invasive species innovate nesting behaviors and increase nest-site availability in the recipient environment, thus facilitating its population growth and invasion process. Potential behavioral innovations in other invasive rose-ringed parakeet populations may be overlooked, and should be considered for effective management plans.

The effects of thinning management on bats and their insect prey in temperate broadleaved woodland

Selection of roosting habitats by Nyctalus noctula and Nyctalus leisleri in Białowieża Forest—Adaptive response to forest management?

Introduction. Holosiivskyi National Nature Park is a unique, by its location, protected area. Parts of the park are located within the administrative boundaries of the city of Kyiv and include extensive, by area, forest plots. The park consists of three parts: Central (Holosiivskyi forest and other tracts), Southern (Lisnyky), and, since 2014, Northern (Svyatoshyn-Bilychi). The latter has the largest area – 6462.62 ha. Data on the chiropterofauna of this massif were incomplete. Bats are an essential element of terrestrial ecosystems. All bat species in Ukraine have a protection status, according to the Red Book of Ukraine and three international treaties. For effective conservation measures for species of this group, it is necessary to own data on their distribution, number, status, etc. As well, the study and monitoring of fauna are one of the primary tasks of national nature parks. Серія «Біологічні науки», 202125Purpose. The aim of the work was to describe the bat fauna of the Svyatoshyn-Bilychi massif of the Holosiivskyi National Nature Park, based on results of the field research conducted in 2019–2020, with the involvement of data collected in 2000–2005.Methods. Catching was carried out with mist nets. Bats were examined by the standard scheme, immediately after their capture. The study was done without removing animals from the wild; bats were released immediately after their examination at the place of their capture. Ultrasonic detectors were used for acoustic observations. The search of roosts was done by social vocalization of bats, presence of feces, night and morning swarming; as well structures which might be potential shelters for bats were inspected.Results. During 2000–2020, at the territory of the Svyatoshyn-Bilychi massif, nine bat species were recorded: Eptesicus serotinus, Myotis dasycneme, M. daubentonii, Nyctalus leisleri, N. noctula,Plecotus auritus, Pipistrellus kuhlii, P. nathusii, P. pygmaeus. Thus, today the list of bat fauna of the Svyatoshyn-Bilychi massif includes 10 species: 9, recorded; 1 species, Nyctalus lasiopterus, known by the record of the first half of the 20th century, was not revealed. According to the results of the survey in 2019–2020, four species were found to be dominants, in terms of the number of record points and their representation in catches: P. nathusii, P. pygmaeus, N. noctula, N. leisleri. During the survey, six species were confirmed to breed at the study area. 11 bat roosts were found; most of them, in trees.Originality. A comprehensive inventory of the chiropterofauna of the large protected area of the Svyatoshyn-Bilychimassif of the Holosiivskyi National Park was carried out for the first time. The first and the only one known Myotis dasycneme maternity colony in Kyiv region was found.Conclusion. The initial description of the chiropterofauna of the Svyatoshyn-Bilychi massif of the Holosiivskyi National Nature Park is presented. The obtained data can be used in the development and further implementation of practical measures for the conservation of bats within the territory of the Holosiivskyi National Nature Park and represent the basis for bat monitoring in the future. Key words: bats, fauna, Holosiivskyi National Nature Park, Kyiv City, Central Ukraine.

The Balkans represent one of the regions with the highest bat diversity in Europe. Thus far, 31 bat species have been recorded in Bosnia and Herzegovina (BiH). The bat fauna of this Balkan country is one of the least studied in Europe. In order to reduce this knowledge gap, bat research was carried out during a ten-day inventory in the vicinity of Čajniče in south-eastern BiH (Republic of Srpska). Mist net surveys resulted in the capture of 15 bat species: Rhinolophus ferrumequinum, R. hipposideros, Myotis brandtii, M. mystacinus sensu lato, M. alcathoe, M. emarginatus, M. nattereri, M. bechsteinii, M. blythii, Nyctalus leisleri, Eptesicus serotinus, Vespertilio murinus, Pipistrellus pipistrellus, P. pygmaeus, and Plecotus auritus. Acoustic surveys resulted in recording one additional species: Barbastella barbastellus. Roost surveys yielded in the finding of three maternity colonies of R. hipposideros. The genetic analysis resulted in the first molecularly confirmed M. brandtii and M. alcathoe records for BiH. Capture of several post-lactating females, sexually active males and multiple juveniles is proof for reproducing populations of these species in the country. During this brief study, we found more than half of all known bat species in BiH in an area of circa 75 km2 .

Natural and anthropogenic factors influencing the bat community in commercial tree stands in a temperate lowland forest of natural origin (Białowieża Forest)

Factors influencing stable nitrogen isotope ratios in wing membranes of insectivorous bat species: A field study