Nationwide trophic cascades: changes in avian community structure driven by ungulates

Nationwide trophic cascades: changes in avian community structure driven by ungulates

In recent decades, many ungulate populations have changed dramatically in abundance, resulting in cascading effects across ecosystems. However, studies of such effects are often limited in their spatial and temporal scope. Here, we contrast multi-species composite population trends of deer-sensitive and deer-tolerant woodland birds at a national scale, across Britain. We highlight the divergent...

Damped trophic cascades driven by fishing in model marine ecosystems.

The largest perturbation on upper trophic levels of many marine ecosystems stems from fishing. The reaction of the ecosystem goes beyond the trophic levels directly targeted by the fishery. This reaction has been described either as a change in slope of the overall size spectrum or as a trophic cascade triggered by the removal of top predators. Here we use a novel size- and trait-based model to...

Trophic cascades in a complex terrestrial community.

To test for direct and indirect effects of a top predator on three lower trophic levels, we conducted two multiyear predator addition experiments in a tropical wet forest. Periodic additions of a top predator (predatory clerid beetle) to a wet forest understory shrub caused a reduction in the predatory beetle's prey (a predatory ant), increased herbivory, and reduced leaf area of the plant. The...

Trophic Cascades in Lakes:

Community-wide trophic cascades and other indirect interactions in an agricultural community

A current goal in ecology is to elucidate the relative roles of primary and secondary consumers versus plant resources in determining community structure and dynamics. The complexity and diversity of terrestrial communities has been hypothesized to strongly influence the strength of these topdown and bottom-up forces, and in turn, trophic interactions are predicted to have significant consequen...