62 research outputs found
The effects of sex, age, season and habitat on diet of the red fox Vulpes vulpes in northeastern Poland
The diet of the red fox Vulpes vulpes was investigated in five regions of northeastern Poland by stomach content analysis of 224 foxes collected from hunters. The red fox is expected to show the opportunistic feeding habits. Our study showed that foxes preyed mainly on wild prey, with strong domination of Microtus rodents, regardless of sex, age, month and habitat. Voles Microtus spp. were found in 73% of stomachs and constituted 47% of food volume consumed. Other food items were ungulate carrion (27% of volume), other mammals (11%), birds (9%), and plant material (4%). Sex- and age-specific differences in dietary diversity were found. Adult males and juvenile foxes had larger food niche breadths than adult females and their diets highly overlapped. Proportion of Microtus voles increased from autumn to late winter. Significant habitat differences between studied regions were found. There was a tendency among foxes to decrease consumption of voles with increasing percentage of forest cover. Based on our findings, red foxes in northeastern Poland can be recognized as a generalist predators, consuming easily accessible and abundant prey. However, high percentage of voles consumed regardless of age, sex, month, or habitats may indicate red fox specialization in preying on Microtus rodents
Teeth of the red fox Vulpes vulpes (L., 1758) as a bioindicator in studies on fluoride pollution
An examination was made of fluoride content in the mandibular first molars of the permanent teeth of the red fox Vulpes vulpes living in north-west (NW) Poland. The teeth were first dried to a constant weight at 105°C and then ashed. Fluorides were determined potentiometrically, and their concentrations were expressed in dry weight (DW) and ash. The results were used to perform an indirect estimation of fluoride pollution in the examined region of Poland. The collected specimens (nâ=â35) were classified into one of the three age categories: immature (im, 6â12 months), subadult (subad, from 12 to 20 months) and adult (ad, >20 months). The mean concentrations (geometric mean) of fluoride were similar in the im and subad groups (230 and 296 mg/kg DW and 297 and 385 mg/kg ash, respectively), and significantly smaller than in the ad group (504 and 654 mg/kg, respectively, in DW and ash). Basing on other reports that the âŒ400 mg/kg DW concentration of fluoride in bones in the long-lived wild mammals generally reflects the geochemical background, it was found that 57% of the foxes in NW Poland exceeded this value by 9% to 170%. This indirectly reflects a moderate fluoride contamination in the tested region
To eat or not to eat? The diet of the endangered iberian wolf (Canis lupus signatus) in a human- dominated landscape in central Portugal
Livestock predation by large carnivores and their persecution by local communities are
major conservation concerns. In order to prevent speculations and reduce conflicts, it is crucial
to get detailed and accurate data on predatorsâ dietary ecology, which is particularly important
in human dominated landscapes where livestock densities are high. This is the case
of the endangered Iberian wolf in Portugal, an endemic subspecies of the Iberian Peninsula,
which has seen its population distribution and abundance decline throughout the 20th century.
Accordingly, the diet of the Iberian wolf was analyzed, using scat analysis, in a humanized
landscape in central Portugal. From 2011 to 2014, a total of 295 wolf scats were
collected from transects distributed throughout the study area, prospected on a monthly
basis. Scat analysis indicated a high dependence of Iberian wolf on livestock. Domestic
goat predominated the diet (62% of the scats), followed by cow (20%) and sheep (13%); the
only wild ungulate present in the scat analysis was the wild boar (4% of the scats). Our results
show that even though livestock constitute most part of wolves diet, different livestock
species may represent different predation opportunities. We conclude that the high levels
of livestock consumption may be a result of low diversity and density of wild ungulates
that settles livestock as the only abundant prey for wolves. Our findings help on the understanding
of the Iberian wolf feeding ecology and have implications for conflict management
strategies. Finally, management implications are discussed and solutions are
recommended
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