Sw. Fisher et al., OF ZEBRA MUSSEL (DREISSENA-POLYMORPHA) LIFE STAGES TO CANDIDATE MOLLUSCICIDES, Journal of shellfish research, 13(2), 1994, pp. 373-377
We developed methods for measuring the toxicity of candidate molluscic
ides to several life stages (preveliger, D-stage veliger, post-D stage
veliger, plantigrade, and adult) of the zebra mussel Dreissena polymo
rpha: Veligers were obtained by inducing ripe adults to spawn in the l
aboratory and by field collection. Plantigrades were collected on slid
es suspended in Lake Erie. The toxicity of candidate molluscicides on
all stages was evaluated in 24 hour static tests in hard standard refe
rence water. The sensitivity of zebra mussel life stages to different
chemicals varied. Veliger stages showed similar sensitivity to Bayer 7
3 and TFM, whereas plantigrades and adults were less sensitive. Sensit
ivity to Calgon H-130, Clamtrol CT-1, and Sal I decreased with each su
ccessive developmental stage; adults were most and preveligers were le
ast sensitive to rotenone. In general, chemical concentrations that ki
ll adults will also be effective against other life stages. However, b
ecause chemical minimization strategies require the use of the smalles
t amount of chemical possible, molluscicides should be tested on the l
ife stage targeted for control.