Foraging paths through vegetation patches for beef cattle in semi-natural pastures

Abstract Grazing semi-natural grasslands may enhance their wildlife faunal diversity and abundance by modifying the plant species composition through exploiting the dietary choices of the domestic livestock, yet diet preferences in these grasslands are often poorly understood. We therefore investigated diet selection of beef cattle in semi-natural pastures, grazed at moderate stocking (MS) or lenient stocking (LS), using the global positioning system (GPS) to track their foraging paths. This was combined with use of an automatic system to record foraging behaviour in free-ranging ruminants and measurements of vegetation structure (pasture height and plant functional groups) at a given location. The diet selected by each animal at each grazing location was then determined from a vegetation map surveyed using GPS along with a geographical information system (GIS). Patches containing clover comprised only 17.5% and 3.1% cover in the MS and LS swards, respectively. Clover was also mostly distributed in the sward as singular patches, rather than as larger aggregated clumps and it appeared that these species were not as strongly selected as has been reported for less heterogeneous pastures where they are more prevalent. This study demonstrated that GPS tracking of livestock foraging paths could be combined with vegetation mapping and automatic grazing behaviour measurements to investigate diet preference in complex, heterogeneous swards.