Parasitic fauna of the invasive house sparrow (Passer domesticus) from Ñuble region, Chile: An example of co-introduced parasites

Abstract

Invasive species impact native wildlife in several ways, as they compete for resources and may transmit their specific pathogens. However, the potential consequences of co-introduced parasites are not fully understood. While the house sparrow (Passer domesticus) was introduced in Chile about a century ago, no data are available regarding its parasites. Thus, the aim of the present study was to determine the parasitic fauna of this avian invader and to determine whether there are co-introduced/co-invasive parasites shared with native birds. One hundred and eight birds were collected from three different localities in the Ñuble region of Chile, and a complete parasitic necropsy was performed in the laboratory. Twenty-three (21.3%) were parasitized by six arthropod species and four (3.7%) were parasitized by two helminth species. Four out of eight taxa are reported for the first time in Chile; among them, three arthropod parasites and the tapeworm, Anonchotaenia globata, are considered as co-introduced parasites. Only A. globata is a potential co-invasive parasite given its low degree specificity in terms of its definitive hosts. Future research should examine whether additional co-introduced/co-invasive parasites have been brought by the house sparrow, and what their potential consequences might be on the health of native birds in Chile.

As espécies invasoras de vertebrados competem com espécies nativas no uso de recursos e transmitem patógenos. Contudo as consequências da co-introdução de parasitos permanecem pouco estudadas. O pardal (Passer domesticus) foi introduzido há um século no Chile, porém não existem dados sobre seus parasitos. O objetivo do estudo foi investigar a fauna parasitária e avaliar se existem espécies co-introduzidas/co-invasivas compartilhadas com as espécies de aves nativas do Chile. Um total de 108 aves foram coletadas em diferentes localidades da região de Ñuble. Seis espécies de artrópodes parasitos foram coletadas de 23 (21,3%) aves. Quatro aves (3,7%) estavam parasitadas por duas espécies de helmintos. Quatro de um total de oito espécies de parasitos correspondem aos primeiros relatos para o Chile. Três artrópodes parasitos e o helminto Anonchotaenia globata são considerados parasitos co-introduzidos no país. Apenas A. globata possui potencial para ser considerada uma espécie co-invasiva, pois pode parasitar Passeriformes em geral. Pesquisas futuras devem investigar se os demais parasitos identificados neste estudo correspondem a espécies co-introduzidas ou co-invasoras e avaliar as possíveis consequências na saúde das aves nativas do país.