Veld condition assessments are unrepresentative at the edges of rotational burn management blocks where grass community composition is atypical

Abstract

Fenced reserves provide benefits for wildlife but are vulnerable to overgrazing. Accurate veld condition assessments are essential to inform stocking density, translocation/culling interventions and burn management decisions. Here, for the first time, we test whether atypical changes in the grass community at the edges of burn management blocks confound the accuracy of veld condition scores. Over a two-year period, 618 sequential parallel transects were conducted 0–240 m from edges of burn blocks and, for comparison, at the core (> 1 km from edge) of burn management blocks in a fenced reserve in South Africa. Veld condition was calculated using the Ecological Index Method. In areas burned recently (∼10 months previously), veld condition scores were unrepresentative within 60 m of the edge due to significant changes in grass community composition (i.e. unrepresentative condition scores were driven by atypical grass communities). In established areas (∼4 years since burning), no edge effect was found for veld condition scores, despite grass composition varying significantly (i.e. condition assessment was robust to community change). For simplicity and consistency, we recommend veld assessments are always conducted > 60 m from edges and that managers consider consequences of reduced veld condition at the edges of recently burned blocks, which could sum to substantial areas.