<P> They were first detected in Canada in the Great Lakes in 1988 , in Lake St. Clair , located east / northeast of Detroit and Windsor . It is believed they were inadvertently introduced into the lakes in the ballast water of ocean - going ships traversing the St. Lawrence Seaway . Another possible , often neglected , mode of introduction is on anchors and chains , although this has not been proven . Since adult zebra mussels can survive out of water for several days or weeks if the temperature is low and humidity is high , chain lockers provide temporary refuge for clusters of adult mussels that could easily be released when transoceanic ships drop anchor in freshwater ports . They have become an invasive species in North America , and as such they are the target of federal policy to control them , for instance in the National Invasive Species Act ( 1996 ) . </P>
<P> They were first detected in Canada in the Great Lakes in 1988 , in Lake St. Clair , located east / northeast of Detroit and Windsor . It is believed they were inadvertently introduced into the lakes in the ballast water of ocean - going ships traversing the St. Lawrence Seaway . Another possible , often neglected , mode of introduction is on anchors and chains , although this has not been proven . Since adult zebra mussels can survive out of water for several days or weeks if the temperature is low and humidity is high , chain lockers provide temporary refuge for clusters of adult mussels that could easily be released when transoceanic ships drop anchor in freshwater ports . They have become an invasive species in North America , and as such they are the target of federal policy to control them , for instance in the National Invasive Species Act ( 1996 ) . </P>
when did zebra mussels come to north america
when did zebra mussels come to north america
1988
1988