Parasites of non-native freshwater fishes introduced into england and wales suggest enemy release and parasite acquisition

When non-native species are introduced into a new range, their parasites can also be introduced, with these potentially spilling-over into native hosts. However, in general, evidence suggests that a high proportion of their native parasites are lost during introduction and infections by some new parasites from the native range might occur, potentially resulting in parasite spill-back to native species. These processes were investigated here using parasite surveys and literature review on seven non-native freshwater fishes introduced into England and Wales. Comparison of the mean numbers of parasite species and genera per population for each fish species England andWaleswith their native ranges revealed\9 % of the native parasite fauna were present in their populations in England and Wales. There was no evidence suggesting these introduced parasites had spilled over into sympatric native fishes. The non-native fishes did acquire parasites following their introduction, providing potential for parasite spill-back to sympatric fishes, and resulted in non-significant differences in overall mean numbers of parasites per populations between the two ranges. Through this acquisition, the non-native fishes also had mean numbers of parasite species and genera per population that were not significantly different to sympatric native fishes. Thus, the non-native fishes in England and Wales showed evidence of enemy release, acquired new parasites following introduction providing potential for spill-back, but showed no evidence of parasite spill-over

Gastrointestinal and external parasitism in the Magellanic Horned Owl Bubo magellanicus (Strigiformes: Strigidae) in Chile

Abstract To describe the parasitic community of the Magellanic Horned Owl, Bubo magellanicus (Aves, Strigiformes), 19 carcasses from central Chile were analyzed. Ectoparasites were collected through plumage inspection, while endoparasites were collected through traditional techniques of parasitological necropsy. Sixteen owls were infected with at least one species of ectoparasite (84.21%) or endoparasite (31.58%). Eleven of 19 birds (57.89%) harbored feather mites of the three species Pandalura cirrata (42.11%), Glaucalges attenuatus (47.37%), and Kramerella sp. (10.53%), whereas 16 individuals (84.21%) harbored the chewing louse Strigiphilus chilensis. Only six birds (31.58%) were infected with helminths; the nematodes Capillaria tenuissima (26.32%) and Dispharynx nasuta (5.26%); the acanthocephalan Centrorhynchus spinosus (5.26%); and the trematode Neodiplostomum sp. (5.26%). Apart from S . chilensis, all parasites comprised new records for B . magellanicus