Developmental stage and level of submersion in water impact the viability of lone star and winter tick eggs

Female ticks deposit large egg clusters that range in size from hundreds to thousands. These egg clusters are restricted to a deposition site as they are stationary, usually under leaf litter and other debris. In some habitats, these sites can be exposed to periodic flooding. When the clusters of tick eggs are disturbed, they may float to the surface or remain underneath organic debris entirely submerged underwater. Here, we examined the viability of egg clusters from winter ticks, Dermacentor albipictus, and lone star ticks, Amblyomma americanum, when partially or fully submerged in water and in relation to the developmental stages of the eggs under lab conditions. In general, egg clusters that were older and partially submerged had a higher viability than fully submerged, younger eggs. Of the two species, A. americanum was more resistant to water exposure. These studies highlight that egg clusters for certain tick species can remain viable when exposed to water for at least two weeks. These results also suggest that distribution by flooding of egg clusters could occur for some species and water submersion will differentially impact tick egg survival based on the specific developmental stage of exposure and species.