The effect of grazing by geese, goats, and fallow deer on soil mites (Acari)

Abstract

The study investigated the effects of grazing by geese, goats, and fallow deer on soil mites. It included a total of 360 samples collected in the spring, summer, and autumn of 2016 and 2017 in north-central Poland. Study plots were situated in three pastures grazed by geese, goats, and fallow deer, and three meadows near the pastures served as controls. All study plots were fenced. In total 22,561 mites (Acari) were obtained, including 15,641 Oribatida (69.3%), 4926 Mesostigmata (21.8%), and 1994 other mites (8.9%). Only the abundance of Oribatida (therefore, also total Acari) differed significantly in pastures grazed by different animal species. The abundance of Oribatida in the pasture vs. the corresponding meadow was higher in the case of geese, similar for fallow deer, and lower for goats. We identified a total of 21 oribatid species. The number of species did not differ significantly between the pastures and the corresponding (mowed) meadows, indicating that they are similarly disturbed biotopes. Eurytopic species characteristic of grasslands predominated in the study plots. The most abundant species were Platynothrus peltifer (C. L. Koch, 1839), Tectocepheus velatus (Michael, 1880), and Eupelops occultus (C. L. Koch, 1835). Platynothrus peltifer and T. velatus preferred pastures to meadows and were most abundant in the goose pasture, while Liebstadia similis (Michael, 1888) and Sellnickochthonius immaculatus (Forsslund, 1942) were more abundant in meadows.