Virtual Poster – A three minute narrated video presentation AFSS/NZFSS Joint Conference 2019

Modelling the influence of environmental and disturbance spatial structure on trait trade-offs in freshwater fish communities (#205)

Finnbar Lee 1 , George Perry 1
  1. University of Auckland, Auckland, New Zealand

Understanding how so many different species can coexist in ecosystems is a long-standing question in community ecology. Species coexistence and community characteristics are frequently explained by environmental heterogeneity, species’ traits and spatial factors such as network structure.

Here we used a metacommunity model to test for relationships between species life-history traits and their responses to variation in environmental and network spatial structure along a disturbance gradient. We used an adaption of the Beverton-Holt discrete-time logistic growth model of multiple competing species. Each species was defined by a set of three traits, (competitive and dispersal abilities and reproductive investment) constrained by a trade-off. We investigated which species traits were favoured across network structures (linear vs intermediate dendritic vs bifurcating) and disturbance rates, as well as how species traits responded to spatial environmental autocorrelation.

We found that environmental spatial structure and disturbance influenced equilibrium life-history traits in communities. Increasing disturbance was associated with increasing investment in reproduction, while spatially structured environments favoured competitive investment. Interactions between disturbance and spatial structure varied across network topologies, indicating trait responses are likely context specific.