TY  - JOUR
A1  - Drygala, Frank
A1  - Werner, Ulrike
A1  - Zoller, Hinrich
T1  - Diet composition of the invasive raccoon dog (Nyctereutes procyonoides) and the native red fox (Vulpes vulpes) in north-east Germany
JF  - Hystrix : the Italian journal of mammalogy
N2  - Invasive alien species pose a great threat to the integrity of natural communities by competition with and predation on native species. In Germany the invasive raccoon dog (Nyctereutes procyonoides) and the native red fox (Vulpes vulpes) occupy a similar ecological niche. Therefore, the aim of our study was to discover the extent of exploitative diet competition between these two generalist carnivores. Carcasses of red foxes (n=256) and raccoon dogs (n=253) were collected throughout Mecklenburg Western-Pomerania (north-east Germany) and stomachs contains were analysed. Frequency of occurrence and biomass share indicate that both canids are omnivorous and pursue opportunistic feeding strategies. Small mammals and edible plant material were the most important food resources for red foxes and raccoon dogs. Nonetheless, interspecies differences were recorded for edible plant material, small mammals and insects. While red foxes mostly feed on voles, raccoon dogs consumed mice and shrews as often as voles. Only raccoon dogs preyed on amphibians. There were no differences in carrion consumption, both species scavenged on wild boar and we found clear competition for carrion year-round. Moreover, there was evidence that two red foxes foraged on raccoon dogs and vice versa. The mean annual interspecies diet overlap index was relatively high. The diets determined for raccoon dogs and red foxes were quite similar and a similar food niche breadth was recorded. However, only minor competition is assumed to take place since differences in feeding habits do exist.
KW  - Nyctereutes procyonoides
KW  - Vulpes vulpes
KW  - invasive species
KW  - diet competition
KW  - feeding strategies
Y1  - 2013
U6  - https://doi.org/10.4404/hystrix.-24.2-8867
SN  - 0394-1914
SN  - 1825-5272
VL  - 24
IS  - 2
SP  - 190
EP  - 194
PB  - Associazione Teriologica Romana
CY  - Roma
ER  - 
TY  - JOUR
A1  - Gervais, Frank
A1  - Siedel, Ulrike
A1  - Heilmann, Britta
A1  - Weithoff, Guntram
A1  - Heisig-Gunkel, Gabriele
A1  - Nicklisch, Andreas
T1  - Small-scale vertical distribution of phytoplankton, nutrients and sulphide below the oxicline of a mesotrophic lake
N2  - A characteristic vertical sequence of phytoplankton populations was observed below the metalimnetic oxycline of a stratified, mesotrophic lake. Ceratium spp., Closterium acutum and Aphanizomenon flos- aquae were present in the epilimnion but had distinct population maxima in the microaerobic chemocline. Below these populations, Cryptomonas phaseolus, Planktothrix clathrata, Pseudanabaena catenata and Limnothrix sp. followed each other in the transition zone between the chemocline and the sulphide-containing hypolimnion. The dominating populations of P. clathrata and P. catenata caused a deep chlorophyll maximum. Phytoplankton structure was determined by the vertical gradients of sulphide and light. Compared with the epilimnion, nutrient availability was not fundamentally better below the oxycline but the algae might have benefited from reduced grazing pressure in their habitat.
Y1  - 2003
UR  - http://plankt.oupjournals.org/cgi/content/full/25/3/273
ER  - 
TY  - JOUR
A1  - Ketelhut, Kerstin
A1  - Bittmann, Frank
A1  - Scheffler, Christiane
A1  - Morgenstern, Ulrike
T1  - Vergleichsuntersuchung über Körpermaße und motorische Fähigkeiten bei Kindern
Y1  - 2003
ER  -