Plant palatability can be inferred from a single-date feeding trial

Abstract

1. Most studies of plant palatability do not consider its seasonal variability, and infer general life-history patterns from single-date feeding experiments. This paper investigates whether different seasonal patterns in the palatability of perennial plant species in one community can alter their relative susceptibility to grazing. 2. The palatability of eight freshwater macrophyte species growing at the same site was monitored during 1 year through nine consecutive feeding experiments using a generalist consumer, the pond snail Lymnaea stagnalis. 3. Plant palatability varied significantly throughout the year, and reached its maximum in autumn. Beyond this general trend, seasonal patterns in palatability differed markedly between species, and two (Callitriche platycarpa and Nuphar lutea) showed no significant seasonal variations. 4. Despite the interspecific differences in seasonal patterns of palatability, species' palatability rankings remained stable throughout the year. Therefore feeding experiments performed at a single sampling date are suitable to assess the relative palatability of a set of species.