Breakdown of Devices

Modified Hester Dendy Sampler

The data from veliger counts is the primary data on the status or presence of zebra mussels. The Modified Hester Dendy device data was used to determine the presence of the juveniles to adults that had attached. Together this data represents the status (presence), relative abundance and life stages found from standardized/proposed sampling. 

A Hester-Dendy apparatus consists of a multiple set of plates that ZM veligers and juveniles can settle on and continue to grow. A modified version of the Hester-Dendy apparatus which consists of five plastic plates. In 2023 thicker plates were used and far less loss of plates occurred. One method of evaluating the intensity of zebra mussel infestation is to mass the accumulated ZM biomass on the colonization plates.