De parasitaire nematode Synhimantus laticeps, geïdentificeerd op basis van de 18S rDNA sequentie, in de maag van een vermagerde Sperwer Accipiter nisus

In autumn 2011, a freshly dead first-year female Sparrowhawk was found in a garden in De Horst, Gelderland. It had probably collided with a wire and was in very poor body condition. It was dissected to examine organ masses and stomach contents. Compared to four other Sparrowhawks in better body condition, the gall bladder was enlarged and the alimentary tract had shrunk, probably both the result of starvation. The stomach was empty except for two nematodes. One of these were identified using 18S rDNA sequencing, most likely Synhimantus laticeps (98%). In the literature, S. laticeps was found to be a common endoparasite in Sparrowhawks with an average prevalence of 22%, which accords to this study, but it seems to vary geographically. In this study, the infected individual was by far the lightest of five examined Sparrowhawks. It is hypothesised that starving raptors are more likely to get infected with parasites by not being capable to maintain an internal environment resistant to parasites, by not producing pellets that would reject parasites, by more likely taking infected prey items, or by more likely eating intestines of prey items. Parasitological studies could benefit from including a more ecological view from the host perspective, to examine effects of e.g. season and the host age and sex on the parasite’s presence, to facilitate better comparison of prevalences, and to clarify the interaction of body condition with parasite infestation.