Occurrence of eggs and oocysts of intestinal parasites of pheasant (Phasianus colchicus) in droppings collected in differently managed protected areas of Tuscany (Italy)

Abstract

The releasing of farm-reared pheasant (Phasianus colchicus) is a very common practice in order to sustain high hunting pressures. However farm-reared birds may be carriers of parasites and diseases for the natural populations. We compared the parasite egg and oocyst prevalence and abundance of excretions found in faecal droppings collected in 13 different protected areas of Tuscany: seven areas where farm-reared pheasants are released every year to increase the reproduction and dispersion of the wild population (restocking areas) and in six areas where the production of pheasants is guaranteed only by the wild population (wild areas). Eimeria spp. oocysts were found in 33 of 129 (25.6%) samples collected in wild areas and in 59 of 119 (51.3%) of samples collected in restocking areas. Nematode eggs were found in 21 of 129 (16.3%) samples collected in wild areas and in 59 of 119 (49.6%) of samples collected in restocking areas. Significant differences were found for Capillaria spp. (31.9% of restocking areas vs. 9.3% of wild areas) and Syngamus spp. (10.1% of restocking areas vs. 3.1% of wild areas) but not for Heterakis or Ascaridia spp. (7.6% of restocking areas vs. 3.9% of wild areas). Parasitic excretion abundance was higher in the droppings collected in restocking areas compared to those collected in wild areas, but differences were significant only for Eimeria and Capillaria spp. In order to reduce the risk of spreading parasites and diseases, we suggest to interpose a strip (larger than the home range of the pheasants) where hunting is not forbidden between the restocking areas and the wild areas, and pheasant releases should not be allowed at least within a “pheasant home range distance” from the wild areas.