Mixed model analyses are given, including the random effects of date and trial, with F-statistic (pond, date, density, turbidity) or Wald Z (trial) and p-values for each effect included in the model.

<p>Significant effects are given in bold. Pond: 11 df, date: 1 df. Models for effects of density and turbidity on foraging gave warnings that the Hessian matrix was not always a positive definite. N = 235 over 12 ponds.