TY - JOUR A1 - Heim, Olga A1 - Puisto, Anna I. E. A1 - Fukui, Dai A1 - Vesterinen, Eero J. T1 - Molecular evidence of bird-eating behavior in Nyctalus aviator JF - Acta ethologica N2 - Insectivorous bats consume a large variety of food items. Previous observations of feathers found in feces led to the hypothesis that the birdlike noctule (Nyctalus aviator, Vespertilionidae) could prey on birds. To test the hypothesis, we analyzed fecal samples from six species (Barbastella pacifica, Murina hilgendorfi, Myotis frater, N. aviator, Plecotus sacrimontis, and Vespertilio sinensis) collected from central Hokkaido, Japan, via DNA barcoding. We identified the presence of the Middendorff’s grasshopper warbler (Locustella ochotensis) in the diet of a pregnant individual of N. aviator. All the other samples proved negative regarding bird prey DNA. This is the first time that the consumption of a bird by N. aviator is confirmed with molecular evidence. Our findings add invaluable insight into the diet of this bat and its potentially opportunistic foraging behavior. KW - Nyctalus aviator KW - Locustella ochotensis KW - Bird prey KW - DNA barcoding KW - Sanger sequencing Y1 - 2019 U6 - https://doi.org/10.1007/s10211-019-00319-5 SN - 0873-9749 SN - 1437-9546 VL - 22 IS - 3 SP - 223 EP - 226 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Heim, Olga A1 - Schröder, Assja A1 - Eccard, Jana A1 - Jung, Kirsten A1 - Voigt, Christian C. T1 - Seasonal activity patterns of European bats above intensively used farmland JF - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Part 2, Letters N2 - Bats are top insect predators on farmland, yet they suffer from intensive farmland management. Here, we evaluated the seasonal activity patterns of European bats above large, arable fields and compared these patterns between ecologically distinct bat species. Using repeated passive acoustic monitoring on a total of 93 arable fields in 2 years in Brandenburg, Germany, we surveyed the activity of different bat species between early spring and autumn. We then used generalized additive mixed models to describe and compare the seasonal bat activity patterns between bat categories, which were build based on the affiliation to a functional group and migratory class, while controlling for local weather conditions. In general, the affiliation to a bat category in interaction with the season in addition to cloud cover and ambient air temperature explained a major part of bat activity. The season was also an important factor for the foraging activity of open-space specialists such as Nyctalus noctula but showed only a weak effect on species such as Pipistreilus nathusii which are adapted to edge-space habitats. Across the seasons, habitat use intensity was high during the period of swarming and migration and low during the energy demanding period of lactation. Seasonal patterns in foraging activity showed that open-space specialists foraged more intensively above agricultural fields during the migration period, while edge-space specialists foraged also during the energy demanding period of lactation. We conclude that the significant seasonal fluctuations in bat activity and significant differences between bat categories in open agricultural landscapes should be taken into consideration when designing monitoring schemes and management plans for bat species in regions dominated by agriculture. Also, management plans should be directed to improve the conditions on arable land especially for bat species which would be classified as narrow-space foragers such as Myotis species. (C) 2016 Elsevier B.V. All rights reserved. KW - Agricultural intensification KW - Seasonality KW - European bat species KW - Functional bat group KW - Migration KW - AgroScapeLabs Y1 - 2016 U6 - https://doi.org/10.1016/j.agee.2016.09.002 SN - 0167-8809 SN - 1873-2305 VL - 233 SP - 130 EP - 139 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Heim, D. M. A1 - Heim, Olga A1 - Zeng, P. A. A1 - Zheng, Jeffrey T1 - Successful Creation of Regular Patterns in Variant Maps from Bat Echolocation Calls JF - Variant Construction from Theoretical Foundation to Applications N2 - We created variant maps based on bat echolocation call recordings and outline here the transformation process and describe the resulting visual features. The maps show regular patterns while characteristic features change when bat call recording properties change. By focusing on specific visual features, we found a set of projection parameters which allowed us to classify the variant maps into two distinct groups. These results are promising indicators that variant maps can be used as basis for new echolocation call classification algorithms. KW - Echolocation KW - Algorithms KW - Morphometry KW - Fourier KW - Analysis KW - Quaternions Y1 - 2019 SN - 978-981-13-2282-2 SN - 978-981-13-2281-5 U6 - https://doi.org/10.1007/978-981-13-2282-2_25 SP - 391 EP - 400 PB - Springer CY - Singapore ER - TY - JOUR A1 - Heim, Olga A1 - Lenski, Johannes A1 - Schulze, Jelena A1 - Jung, Kirsten A1 - Kramer-Schadt, Stephanie A1 - Eccard, Jana A1 - Voigt, Christian C. T1 - The relevance of vegetation structures and small water bodies for bats foraging above farmland JF - Basic and applied ecology : Journal of the Gesellschaft für Ökologie N2 - Bats are known to forage and commute close to vegetation structures when moving across the agricultural matrix, but the role of isolated landscape elements in arable fields for bat activity is unknown. Therefore, we investigated the influence of small isolated ponds which lie within arable fields close to vegetation structures on the flight and foraging activity of bats. Additionally, we compared species-specific activity measures between forest edges and linear structures such as hedgerows. We repeatedly recorded bat activity using passive acoustic monitoring along 20 transects extending from the vegetation edge up to 200 m into the arable field (hereafter: edge-field interface) with a small pond present at five transects per edge type (linear vs. forest). Using generalized linear mixed effect models, we analyzed the effects of edge type, pond presence and the season on species-specific flight and foraging activity within the edge-field interface. We found a higher flight activity of Nyctalus noctula and Pipistrellus pygmaeus above the arable field when a pond was present. Furthermore, Pipistrellus nathusii and Pipistrellus pipistrellus foraged more frequently at forest edges than at linear structures (e.g. hedgerows). Additionally, we found three major patterns of seasonal variation in the activity of bats along the edge-field interface. This study highlights the species-specific and dynamic use of forest and hedgerow or tree line edges by bats and their importance for different bat species in the agricultural landscape. Further, additional landscape elements such as small isolated ponds within arable fields might support the activity of bats above the open agricultural landscape, thereby facilitating agroecosystem functioning. Therefore, additional landscape elements within managed areas should be restored and protected against the conversion into arable land and better linked to surrounding landscape elements in order to efficiently support bats within the agroecosystem. KW - Hedgerow KW - Forest edge KW - Pond KW - European bats KW - Agricultural landscape KW - Wind turbines Y1 - 2017 U6 - https://doi.org/10.1016/j.baae.2017.12.001 SN - 1439-1791 SN - 1618-0089 VL - 27 SP - 9 EP - 19 PB - Elsevier GMBH CY - München ER -