Livestock disturbances in Mediterranean temporary ponds: A mesocosm experiment with sheep manure and simulated trampling

The number and quality of temporary wetlands are declining worldwide and many of the remaining habitats are used as pastures and drinking sites for livestock. Livestockcan impact wetlands through a combination of herbivory (defoliation), trampling(physical disturbance), and defecation(nutrient input), but how these influence community structure is still poorly understood. It is nonetheless generally accepted that wetland management can include some grazing, and that properly managed livestockcan play a major role in wetland conservation. In Mediterranean temporary ponds, however, it is suggested that grazing might negatively affect macrophytebiodiversity within the pondbasin. The impact of livestockon the characteristic freshwater fauna also remains understudied. Using an outdoor mesocosmexperiment, we focused on two effects of sheep livestock( tramplingand defecation) and their combination, on water quality and on faunal and floral communities from Moroccan temporary ponds. Communities from forested and agricultural sites ( pondtype) were also compared in a factorial design with treatments. We found that sheep‐simulated tramplingand nutrient input decreased hatching invertebrate and plant richness, while lasting effects on water quality and actively colonising communities were limited. Temporary pondcommunities from forested and agricultural sites differed in species composition and interacted with treatments in their effects on hatching crustaceans and macrophytespecies composition. Treatments had a larger effect on the species composition of forest pondscompared to agricultural ponds. These results highlight the complex effects livestockmay have on aquatic communities. Water quality, taxonomic groups, and trophic levels responded negatively to tramplingand waste treatmentsand these responses changed with pondtype. With worldwide declines of seasonal wetland habitat, the effects of land use (i.e. livestockgrazing) on these ecosystems and their biota are important to consider for integrated and sustainable management.