Human-induced biotic invasions and changes in plankton interaction networks

1.Pervasive and accelerating changes to ecosystems due to human activities remain major sources of uncertainty in predicting the structure and dynamics of ecological communities. Understanding which biotic interactions within natural multitrophic communities are threatened or augmented by invasions of non-native species in the context of other environmental pressures is needed for effective management. 2.We used multivariate autoregressive models with detailed time-series data from largely freshwater and brackish regions of the upper San Francisco Estuary to assess the topology, direction and strength of trophic interactions following major invasions and establishment of non-native zooplankton in the early 1990s. We simultaneously compared the effects of fish and clam predation, environmental temperature, and salinity intrusion using time-series data from > 60 monitoring locations and spanning more than three decades. 3.We found changes in the networks of biotic interactions in both ...