@article{WallschlaegerHelb1994,
  author    = {Wallschl{\"a}ger, Hans-Dieter and Helb, Hans-Wolfgang},
  title     = {Geographic variation in the scarlet grosbeak : research notes on avian biology},
  year      = {1994},
  language  = {en}
}
@article{Wallschlaeger1994,
  author    = {Wallschl{\"a}ger, Hans-Dieter},
  title     = {On the song of Sylvia curruca, Sylvia nana and Sylvia communis in Mongolia},
  year      = {1994},
  language  = {en}
}
@article{HanschWallschlaeger1996,
  author    = {Hansch, Petra and Wallschl{\"a}ger, Hans-Dieter},
  title     = {Vocalisation of curassows (Cracidae)},
  year      = {1996},
  language  = {en}
}
@article{HelbWallschlaeger1996,
  author    = {Helb, Hans-Wolfgang and Wallschl{\"a}ger, Hans-Dieter},
  title     = {Geographical variation of the song of the scarlet rosefinch Carpodacus erythrinus},
  year      = {1996},
  language  = {en}
}
@misc{NeyeWallschlaegerTiedemann2006,
  author    = {Neye, Gundula and Wallschl{\"a}ger, Hans-Dieter and Tiedemann, Ralph},
  title     = {Song dialect boundaries in the Yellowhammer: Do they restrict gene flow?},
  series = {Journal of ornithology},
  volume    = {147},
  journal   = {Journal of ornithology},
  number    = {Supplement 1},
  publisher = {Blackwell},
  address   = {New York},
  issn      = {0021-8375},
  pages     = {219 -- 219},
  year      = {2006},
  language  = {en}
}
@article{HlinakMuehleWerneretal.2006,
  author    = {Hlinak, Andreas and M{\"u}hle, Ralf-Udo and Werner, Ortrud and Globig, Anja and Starick, Elke and Schirrmeier, Horst and Hoffmann, Bernd and Engelhardt, Andreas and H{\"u}bner, Dagmar and Conraths, Franz J. and Wallschl{\"a}ger, Hans-Dieter and Kruckenberg, Helmut and M{\"u}ller, Thomas},
  title     = {A virological survey in migrating waders and other waterfowl in one of the most important resting sites of Germany},
  issn      = {0931-1793},
  year      = {2006},
  abstract  = {Wild birds are considered a potential reservoir or a carrier of viral diseases and may therefore play a role in the epidemiology of economically important or zoonotic diseases. In 2001 and 2002, a survey with special emphasis oil virus isolation in migrating waders and some other birds were conducted. In one of the most important inland resting sites for migratory waterfowl, tracheal and cloacal swabs were collected from 465 waders representing 19 different species, and 165 other birds that were not captured on purpose. A total of 42 avian viruses were isolated, 34 of these were identified as paramyxoviruses (PMVs). The majority of isolates came from waders and wild ducks, and were characterized as PMV-1. In contrast, PMV-4 was found in wild ducks only, PMV-6 was mainly detected in wader species. Four avian influenza viruses (ATVs), belonging to H4 and H3 haemagglutinin subtype, were isolated from wild duck species. Furthermore, four reo-like viruses were isolated from one particular wader species for the first time. The majority of virus positive birds were < 1 year old and did not show any clinical symptoms. There was no evidence for the presence of West Nile virus in these birds. These results confirm that the restricted resting sites in Western Europe must be considered as important locations for the intra- and interspecies transmission of avian viruses},
  language  = {en}
}
@article{WonkeWallschlaeger2009,
  author    = {Wonke, Gundula and Wallschl{\"a}ger, Hans-Dieter},
  title     = {Song dialects in the yellowhammer Emberiza citrinella : bioacoustic variation between and within dialects},
  issn      = {0021-8375},
  doi       = {10.1007/s10336-008-0326-6},
  year      = {2009},
  abstract  = {The yellowhammer Emberiza citrinella is a common European bird that sings in dialects that for decades have been distinguished by the existence of one single element (called a "specific''). In this study we looked into other possibilities for dialect discrimination, measuring 24 different variables. For the first time, multivariate statistics were used to discriminate dialect in yellowhammer song. Two similar dialects (XlB and XsB) that are not clearly defined in the literature were studied. Statistics incorporated (1) all variables, ( 2) no variables of "specific'' elements, and (3) no variables under the influence of these "specific'' variables. Multivariate statistics support dialect discrimination by ear and confirmed that only one element in yellowhammer song characterises dialect. In addition, we looked for local differences within two dialects and found that one local observation area showed a higher separation than the other sites (Meck1). However, as yet there is insufficient evidence for the existence of a new subdialect.},
  language  = {en}
}
@article{ItonagaKoeppenPlathetal.2011,
  author    = {Itonaga, Naomi and K{\"o}ppen, Ulrich and Plath, Martin and Wallschl{\"a}ger, Hans-Dieter},
  title     = {Declines in breeding site fidelity in an increasing population of White Storks Ciconia ciconia},
  series = {IBIS},
  volume    = {153},
  journal   = {IBIS},
  number    = {3},
  publisher = {Wiley-Blackwell},
  address   = {Malden},
  issn      = {0019-1019},
  pages     = {636 -- 639},
  year      = {2011},
  abstract  = {Following a steep decline, White Stork Ciconia ciconia populations in Germany are currently increasing, allowing us to examine potential density-dependent effects on breeding dispersal. Our data suggest that the proportion of breeding dispersers has increased over time, indicating a density-dependent component in nest-site fidelity that may be linked to increased competition.},
  language  = {en}
}
@article{TschoepeWallschlaegerBurkartetal.2011,
  author    = {Tsch{\"o}pe, Okka and Wallschl{\"a}ger, Hans-Dieter and Burkart, Michael and Tielb{\"o}rger, Katja},
  title     = {Managing open habitats by wild ungulate browsing and grazing a case-study in North-Eastern Germany},
  series = {Applied vegetation science : official organ of the International Association for Vegetation Science},
  volume    = {14},
  journal   = {Applied vegetation science : official organ of the International Association for Vegetation Science},
  number    = {2},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {1402-2001},
  doi       = {10.1111/j.1654-109X.2010.01119.x},
  pages     = {200 -- 209},
  year      = {2011},
  abstract  = {Question: Can wild ungulates efficiently maintain and restore open habitats? Location: Brandenburg, NE Germany. Methods: The effect of wild ungulate grazing and browsing was studied in three successional stages: (1) Corynephorus canescens-dominated grassland; (2) ruderal tall forb vegetation dominated by Tanacetum vulgare; and (3) Pinus sylvestris-pioneer forest. The study was conducted over 3 yr. In each successional stage, six paired 4 m(2)-monitoring plots of permanently grazed versus ungrazed plots were arranged in three random blocks. Removal of grazing was introduced de novo for the study. In each plot, percentage cover of each plant and lichen species and total cover of woody plants was recorded. Results: Wild ungulates considerably affected successional pathways and species composition in open habitats but this influence became evident in alteration of abundances of only a few species. Grazing effects differed considerably between successional stages: species richness was higher in grazed versus ungrazed ruderal and pioneer forest plots, but not in the Corynephorus sites. Herbivory affected woody plant cover only in the Pioneer forest sites. Although the study period was too short to observe drastic changes in species richness and woody plant cover, notable changes in species composition were still detected in all successional stages. Conclusion: Wild ungulate browsing is a useful tool to inhibit encroachment of woody vegetation and to conserve a species-rich, open landscape.},
  language  = {en}
}
@article{KruckenbergMuellerFreulingetal.2011,
  author    = {Kruckenberg, Helmut and M{\"u}ller, Thomas and Freuling, Conrad and M{\"u}hle, Ralf-Udo and Globig, Anja and Schirrmeier, Horst and Buss, Melanie and Harder, Timm and Kramer, Matthias and Teske, Kathrin and Polderdijk, Kees and Wallschl{\"a}ger, Hans-Dieter and Hlinak, Andreas},
  title     = {Serological and virological survey and resighting of marked wild geese in Germany},
  series = {European journal of wildlife research},
  volume    = {57},
  journal   = {European journal of wildlife research},
  number    = {5},
  publisher = {Springer},
  address   = {New York},
  issn      = {1612-4642},
  doi       = {10.1007/s10344-011-0514-1},
  pages     = {1025 -- 1032},
  year      = {2011},
  abstract  = {In order to investigate the potential role of arctic geese in the epidemiology, the spatial and temporal spread of selected avian diseases, in autumn 2002, a virological and serological survey designed as capture-mark-resighting study was conducted in one of the most important coastal resting sites for migratory waterfowl in Germany. Orophatyngeal, cloacal swabs and blood samples were collected from a total of 147 birds comprising of three different arctic geese species including White-fronted Goose (Anser albifrons), Tundra Bean Goose (Anser fabalis rossicus), Pink-footed Goose (Anser brachyrhynchus) as well as from 29 non-migratory Canada Geese (Branta canadensis). Altogether, six adeno-like viruses (ALV; 95\% CI, 1.74-9.92\%) and two avian paramyxoviruses (APMV-4; 95\% Cl, 0.19-5.53\%) were isolated mainly from juvenile White-fronted Geese. In addition, four Canada Geese were infected with lentogenic APMV-1 (95\% CI, 3.89-31.66\%) at the date of sampling. No avian influenza viruses, reo-like viruses could be isolated despite serological evidence. Likewise, no evidence of current or previous infection by West Nile virus was found. Of the 147 birds tagged in the following years, 137 birds were resighted between 2002 and 2008 accumulating to 1925 sightings. About 90\% of all sightings were reported from the main wintering and resting sites in Germany and The Netherlands. Eight of the resighted geese were virus positive (ALV and APMV-4) at the time point of sampling in 2002.},
  language  = {en}
}