Comparison of Red Fox Vulpes Vulpes and Pine Marten Martes Martes Food Habits in a Deciduous Forest in Hungary

Abstract

Feeding habits and interspecific trophic niche overlap of two sympatric predators, the pine marten Martes martes and the red fox Vulpes vulpes, were studied in a deciduous forest habitat in Hungary with conditions of differing abundance and dominance in the rodent community. The main food source of the predators consisted of small mammals, mainly rodents. Consumption of small mammals was higher during bank vole Clethrionomys glareolus dominated years than in Apodemus mice dominated years. Both predators preferred bank voles as prey and consumed less Apodemus mice and shrews (Soricidae) than expected by availability. The two opportunistic predators utilised different, seasonally-dependent food resources. Martens consumed more plants, reptiles, amphibians and fish, whereas foxes consumed more small mammals and ungulate carcasses. In summer and autumn, percent biomass of bank voles in marten diet and Apodemus mice in fox diet was positively correlated with the number of rodents in the available food resources. In winter and spring, the density of rodents varied slightly; therefore, variations in the diets of these two predators were not related to prey density. The prey consumed was characteristically terrestrial and small sized (, 50 g). There was no difference in prey weight distribution between martens and foxes, but martens consumed more arboreal and foxes more terrestrial prey. The standardised food niche breadth did not differ significantly between the two species. Food niche overlap between the two predators was higher in winter and spring, but the difference between seasons was not significant (mean overlap 5 72%). In comparison with higher latitudes, we found a larger food niche overlap in our study.

Spatio-temporal variation of predator diet in a rural habitat: stone martens in the villages of Białowieża forest

“…The marten's dietary composition varied seasonally, between years and in relation to village size. Many other generalist predators have shown a similar spatial and temporal flexibility of dietary composition and plasticity, in their capacity to adapt to changing abundances of food resources within the environment (Jędrzejewski and Jędrzejewska 1992;Lanszki et al 1999Lanszki et al , 2007Borkowski et al 2011;Kidawa and Kowalczyk 2011). Seasonal and inter-annual variation in dietary composition has also been observed in other martens.…”

“…Seasonal and inter-annual variation in dietary composition has also been observed in other martens. Pine marten, sable (Martes zibellina) and American marten (Martes americana) diets have been shown to be primarily dependent on the abundance of rodents (Thompson and Colgan 1990;Jędrzejewski et al 1993;Helldin 1999;Zalewski 2004Zalewski , 2007Lanszki et al 2007;Dubinin 2010;Balestrieri et al 2011). In seasons, or years when abundance of their main prey is low, these marten species supplement their diet with other food sources, e.g.…”

“…In seasons, or years when abundance of their main prey is low, these marten species supplement their diet with other food sources, e.g. birds, shrews, fruits or carcasses of ungulates (Jędrzejewski et al 1993;Lanszki et al 1999Lanszki et al , 2007Zalewski 2004). The population densities and dynamics of these marten species have been related to rodent abundance (Thompson and Colgan 1987;Zalewski and Jędrzejewski 2006).…”

Habitat use and home range size of red foxes in Prince Edward Island (Canada) based on snow-tracking and radio-telemetry data

“…This may be used as indirect evidence supporting the idea that foxfeeding is altering the way that red foxes use habitats in Stanhope. In Stanhope, red foxes did not show much preference for habitats such as forests, abandoned fields, and shrubs, in which they would normally have to hunt for prey such as small mammals (e.g., [16,[37][38][39][40]). Movement-segments within both dunes and human-use areas tended to be longer than in other habitat types.…”

“…Interestingly, we found that in both sites foxes used forested areas less than expected based on their availability. A possible explanation for this finding is that rodents, often a main prey of foxes (e.g., [39][40]), were more accessible in other habitat types. Several studies have shown that red fox uses forested areas significantly more than expected based on their availability mainly due to both low snow accumulation and the ability to forage for small mammals [38,41].…”