Changes in host-parasitoid food web structure with elevation

Gradients in elevation are increasingly used to investigate how species respond to changes in local climatic conditions. While many studies have shown elevational patterns in species richness and turnover, little is known about how food web structure is affected by elevation. Contrasting responses of predator and prey species to elevation may lead to changes in food web structure. We investigated how the quantitative structure of a herbivore-parasitoid food web changes with elevation in Australian subtropical rainforest. On four occasions, spread over one year, we hand-collected leaf miners at twelve sites, along three elevational gradients (between 493 m and 1159 m a.s.l). A total of 5030 insects, including 603 parasitoids were reared, and summary food webs were created for each site. We also carried out a replicated manipulative experiment by translocating an abundant leaf-mining weevil, Platynotocis sp., which largely escaped parasitism at high elevations (≥900m a.s.l.), to lower, wa...