alien species introductions in the Great Lakes of North America 
{5.5.1}: between 1959 and 2006, one new alien species was 
discovered every seven months, but there was an abrupt 
shift (85 per cent decline) in the number of newly established 
alien species following the implementation of the ballast water 
regulations by Canada and the United States of America in 
2006 and 2008 respectively {Box 2.9}.
29SUMMARY FOR POLICYMAKERS
19SUMMARY FOR POLICYMAKERS
BACKGROUND
Box SPM 2 The International Convention for the Control and Management of Ships' 
Ballast Water and Sediments: an example of international collaboration to 
prevent biological invasions.