Cattle disperse microalgae by epizoochory in Neotropical wetlands

The role of cattle in the epizoochorous dispersal of microalgae in Neotropical wetlands is poorly understood. Here, we assessed the potential of cattle to transport algae externally in isolated wetlands surrounded by grassland matrices in southern Brazil. We examined whether the richness and composition of microalgae attached to cattle coats reflected those found in the environment and whether dispersal patterns were linked to algal functional traits. Sampling 62 cows from two dairy farms, only three individuals showed no algal taxa adhered to their coats. We identified 80 algal species on the animals and 105 species in the wetlands, 47 of which also occurred on the cattle coats, representing approximately 45% of the species recorded in the environment. Pennate diatoms and flagellated algae were the most common morpho-functional groups on cow coats, suggesting that cattle mediate dispersal in a trait-selective manner. The substantial algal diversity detected on cows’ legs indicates that livestock can enhance connectivity and gene flow among microalgal populations across isolated wetlands in grassland landscapes, contributing to the ecological connectivity among isolated wetlands.