Figure 2

Isotopic niche biplot of BEFORE (a) and AFTER (b) communities. Each point represents a sample. The legend shows the respective colours of consumers and basal resources. Full symbols represent the basal resources of the respective study location. Empty coloured symbols represent the basal resources of the other study location. The isotopic niche space was divided into Isotopic Trophic Units (ITUs), i.e. squares having 1 × 1‰ ranges of δ¹⁵N and δ¹³C values, which were defined as groups of individuals occupying the same position in the δ¹³C-δ¹⁵N niche space. Dashed-line polygons delimit the convex hull (Total Area) of consumers.