Habitat fragmentation is a leading cause of biodiversity loss worldwide and commonly negatively impacts species at higher trophic levels and parasites. Parasites are increasingly recognized for their importance in maintaining ecosystem function, but few studies have looked at fragmentation’s long-term effect on them. Existing studies show that parasites have varied responses to fragmentation and are largely dependent on the responses of their hosts. We asked how a host-parasite relationship involving a skink definitive host (Lampropholis guichenoti), amphipod intermediate host (Arcitalitrus sylvaticus), and parasitic nematode (Hedruris wogwogensis) changed in the short- versus long-term after experimental forest fragmentation in the Wog Wog Habitat Fragmentation Experiment in southeastern Australia.
Results/Conclusions
Previously, we determined that fragmentation drove declines in nematode infection rates in remnant fragments and the nonnative pine plantation matrix, compared to undisturbed continuous forest, immediately following fragmentation. These reductions in infection in the fragments and matrix were driven by changes in amphipod abundance, which were, in turn, driven by changes in the abiotic environment of fragments and the matrix. This disruption in the host-parasite relationship ameliorated over time as the matrix matured and amphipods repopulated all parts of the landscape. Preliminary data from necropsied skinks sampled 23 years after fragmentation suggest that recovery of amphipods in the fragments and matrix restored this host-parasite interaction. We conclude that the intermediate host is critical in maintaining and reestablishing host-parasite relationships that may have been previously disrupted. In addition, short-term responses after large scale disturbance events like habitat fragmentation may not predict how parasites that rely on trophic transmission will respond in the long-term.