Permanent mountain ponds support higher richness and abundances of macroinvertebrates than temporary ones

Abstract Mountain ponds are vulnerable to climate change, particularly because of their dependence on precipitation for inundation. Pond functioning, and survival of macroinvertebrate communities, is tied to water permanence, among other factors such as altitude. Few studies examined the relationship between water permanence and the macroinvertebrate community as a whole in mountain ponds. We investigated permanent and temporary mountain ponds in the Pre-Pyrenees in Spain, and collected macroinvertebrate samples in spring and autumn of 2023 and 2024. Significant differences in environmental parameters between temporary and permanent ponds highlighted distinct conditions for community development. Species richness was higher in permanent and in larger ponds, and decreased with increasing altitude. Macroinvertebrate abundances were lower in temporary mountain ponds, with few exceptions, linked to mass occurrence of taxa such as Chirocephalus diaphanus (Anostraca). Community evenness was higher in temporary ponds. Seventeen percent of the variation in community composition was explained by pond size and altitude. Although the influence of water permanence and macrophyte cover was not statistically significant, their alignment with the ordination suggests an influence on community structure. Our study contributes knowledge for management and conservation of mountain pond communities, and highlights the importance of maintaining heterogeneity in water permanence in mountain pondscapes.