How does host ecology influence sampling effort in parasite diversity estimates? A case study using Neotropical freshwater fishes

Accurately estimating biodiversity is fundamental to ecological understanding and prediction. Helminthes are often neglected in biodiversity estimates and when included are often underestimated. Here we examine how sampling effort affects estimates of parasite diversity in an assemblage of freshwater fish from a floodplain in Brazil. We also examine how ecological and behavioral factors influence the sampling effort necessary to accurately estimate the parasite diversity associated with a fish species. We use our dataset to suggest that host species with wide geographic distribution (i.e., long migrations), gregarious behavior (i.e., shoal), larger body size, higher population density, wide diet breadth (i.e., omnivorous), and autochthonous origin, increase the effort necessary to estimate the total diversity of parasites. However, estimating this parasitic fauna has several restrictions and limitations, due to the highly complex of the floodplain ecosystems, with non-linear and non-random responses.