Fig. 4.

Isotope bi-plots indicating the mean (±standard error) for chub, crayfish, and the putative prey of both species, for a the Rother and b Chad Brook. For the Rother small fish were 1+ cyprinids, Phoxinus phoxinus, Cottus gobio, and Barbatula barbatula, aquatic invertebrates were Trichoptera, Gammarids, and Ephemeroptera, and terrestrial invertebrates were Formicidae, Arachnidae, Hemiptera, Diptera, and Coleoptera. For Chad Brook small fish were Phoxinus phoxinus, Cottus gobio, Barbatula barbatula, and Gasterosteus aculeatus, aquatic invertebrates were Gammarids, Calopteryx sp., Heteroptera, Limnaea, and Trichoptera, and terrestrial invertebrates Formicidae, Arachnidae, Diptera, Coleoptera, and Gastropoda