A new study published in the Journal of Helminthology has found that migratory birds may carry fewer parasites between islands than previously believed. Researchers from the Estonian University of Life Sciences, the Swedish University of Agricultural Sciences, and collaborators in Greenland and the Faroe Islands analyzed DNA to track the spread of Diplostomum parasites.
The findings challenge the common assumption that birds readily transport parasites over large geographic distances. This suggests that parasite dispersal across North Atlantic islands is far more constrained than expected.
The team used genetic data to trace the movement of these flatworm parasites, which infect birds as part of their life cycle. The study revealed surprisingly limited genetic mixing between populations on different islands.
These results could reshape how scientists model disease spread in migratory species. Conservation efforts may need to reconsider the role of bird migration in parasite distribution.
Experts note the study's focus on one parasite genus may limit broader conclusions. Further research across multiple parasite groups is needed to confirm the pattern.