Data from: Parasite transmission stage abundance varies in lakes over time and space

Environmentally transmitted parasites produce transmission stages that can
remain viable and infective for extended periods of time in the
environment where susceptible hosts may encounter them. Although many
parasites have this mode of transmission, the abundance and distribution
of environmental transmission stages have largely been overlooked,
especially in aquatic habitats. Without empirical data to characterize
spatial and temporal dynamics of parasite transmission stages in the
environment, we might make incorrect assumptions about host-parasite
contact rates. For aquatic environments, seasonal habitat structure driven
by thermal stratification has been hypothesized to affect the patchiness
of transmission stages within the water column, leading to uneven exposure
risk to hosts. In this study, we quantified transmission stage
concentrations of five common parasites of Daphnia spp. and Ceriodaphnia
dubia at every meter of the water column at the deep basin of six lakes in
southeastern Michigan every two weeks from June to November 2021. We found
that transmission stage concentration varied by orders of magnitude over
time and with depth. We investigated several possible drivers of these
spatial and temporal patterns. For instance, our results suggest that
greater mixing depth decreased transmission stage vertical patchiness
within the water column of lakes with lower Fee’s p values. However,
horizontal spore patchiness across a lake was not correlated with the
nearshore-offshore gradient of our study lakes. Overall, the results of
our study show that parasite transmission stage concentrations have
spatial and temporal dynamics that could affect disease dynamics within
highly structured aquatic environments.