
208 Environmental Impact Analysis
A series of veliger studies was designed and conducted to evaluate the
potential impact of spreading and increasing the density of the invasive mus-
sels in the Great Lakes via larval dispersal. Veligers (both zebra and quagga)
were introduced to aquaria with native sediment and the three DCR types:
some uncovered, some covered with 1 mm of sediment, and others covered
with 3 mm of sediment. The results showed that up to 6% of the veligers pres-
ent in the experiment attach to DCR, compared with virtually zero percent
attachment to natural sediments (Figure 5.16). Even a 1 mm cover of natural
sedimen