Alien parasite hitchhikes to Patagonia on invasive bumblebee

ARBETMAN, M.P., I. MEEUS, C.L. MORALES, M.A. AIZEN Y G. SMAGGHE

BIOLOGICAL INVASIONS

SPRINGER

Lugar: Berlin; Año: 2013 vol. 15 p. 489 - 494

1387-3547

The worldwide trade in bumblebees can lead to spread of diseases, which in turn has been claimed as a driver of bumblebee decline. Populations of the introduced Bombus terrestris, which invaded NW Patagonia, Argentina, in 2006, harbor the highly pathogenic protozoan Apicystis bombi. We asked whether A. bombi was co-introduced with B. terrestris, and if yes, whether it was spilled over to the two resident bumblebee species in the region: the introduced European Bombus ruderatus and the native Bombus dahlbomii. We searched for A. bombi by means of PCR in samples of B. ruderatus and B. dahlbomii collected before and after the invasion of B. terrestris and in samples of this latter species. We found no A. bombi in samples of B. ruderatus and B. dahlbomii collected before B. terrestris invasion. In contrast, we found A. bombi in both resident species as well as in B. terrestris, after its invasion,. The identity of the parasite was confirmed sequencing the 18s region, which was identical for the three bumblebee species and matched the European sequence. This is the first report of A. bombi in B. ruderatus and B. dahlbomii. Moreover our results suggest that Patagonia was free from A. bombi and that this parasite was co-introduced with B. terrestris, and spilled over in situ to these two previously resident species. Finally, our findings provide indirect circumstantial evidence of a potential link between the population collapse and geographic retraction of B. dahlbomii and the introduction of this novel parasite.