They cautioned that future modeling of earthquake response in the delta should take the findings into account for land use planning. Although earthquakes have not damaged the Vancouver area in historical times, Luternauer said historical and geological records indicate the region could experience an off-shore interplate earthquake greater than magnitude 8.0. In 1991, Kelly studied ballast sediment from woodchip ships entering Tacoma and Port Angeles. She found a wide range of viable organisms, including dinoflagellates, one of which includes toxic species in its genus. Kelly cited 40 non-native species introductions around the world attributed to ballast discharge.
Biological invasion is very complex.
Each situation is so specific and unique we can't predict them. One measure to reduce the risk is managing ballast discharge in coastal waters. They realize the need to resolve the issue without unduly restrictive legislation. But there are many different ideas about what the alternative should be. As resource managers aim to protect more and more species, however, broader habitat requirements are not fully understood.