The diet composition and prey selection of grey wolves (Canis lupus) inhabiting the Roztocze and Solska Forest (south-east Poland) was studied based on an analysis of scats collected in 2001-2002 (n = 84) and 2017-2020 (n = 302). In both periods, wolves preyed mainly on wild ungulates (96.5-96.7% of consumed biomass). Roe deer (Capreolus capreolus) was the most critical wolf prey accounting for 57.8% of consumed biomass in 2001-2002 and 49.2% and 2017-2020, but wolves positively select only wild boar (Jacob's selectivity index D = 0.213 in 2001-2002 and 0.710 in 2017-2020) and fallow deer (D = 0.588 only in 2017-2020). The largest species – moose Alces alces and red deer Cervus elaphus – were consumed less than expected from their share in the ungulate community. Predation on medium-sized wild mammals and domestic animals was low, 0.8-2.2% and 1.1-2.7% of the biomass consumed, respectively. The breadth of the wolf diet was very narrow and identical in both study periods (B = 1.07), while the similarity of diet composition was high (α = 0.999). This study indicated the stability of the wolf diet over two decades and the importance of wild boar as a food source for this carnivore.
Macrolophus pygmaeus (Hemiptera: Miridae) is an important predator of pests of horticultural crops and here its ability as a predator of Acyrthosiphon pisum (Hemiptera: Aphididae) is addressed for the first time. The percentage predation of the different aphid instars and the number partially consumed were studied. Our results, obtained using choice and no-choice tests, revealed that M. pygmaeus caught and consumed more young than later instars of A. pisum, which confirms results of previous studies using other species of aphids. We also studied the interactions between predators (male/female) foraging in the same patch. When the prey/predator ratio is kept constant at 10 : 1 the average percentage of aphids completely consumed by individual females or males does not change with increase in the number of foraging predators. However, the number of partially consumed aphids decreased when females shared the same patch. In contrast, there was an increase in the number of aphids partially consumed when two males shared the same patch. The results were discussed in terms of potential predator foraging strategies since intraspecific competition is a key factor modulating the dynamics of prey-predator systems., Juliana Durán Prieto, Vincenzo Trotta, Paolo Fanti, Cristina Castañé, Donatella Battaglia., and Obsahuje bibliografii