The Transfer of Harmful Aquatic Organisms and Pathogens with Ballast Water and Their Impacts - Global Maritime Transport and Ballast Water Management: Issues and Solutions - page 40

Table 1 Summary of European BWS studies indicating each study source, when it was conducted,
number of vessels sampled, number of samples and number of taxa identifi ed
Source When Vessels sampled Samples taken Taxa identifi ed
Belgium 1995-1998 5 32 28
Denmark 2000-2001 1 8 4
England & Wales 1996-1999 132 265 320
Germany 1992-1999 198 215 521
Lithuania 1999-2000 11 22 90
Netherlands 1999-2000 17 23 88
Norway 1996-1999 51 12 184
Scotland 1994-1997 127 226 327
Slovenia 2003 15 90 134
Sweden 1996 3 >3 41
EU-CA 1998-1999 5 705 67
Total 1994-2003 565 1598 a More than
1,000
Gollasch ( 1996 ), Macdonald and Davidson ( 1998 ), Gollasch et al. ( 2000a , b ), Olenin et al. ( 2000 ),
Gollasch et al. ( 2002 ) and David et al. ( 2007 )
a An approximation was made because several taxa were identifi ed in more than one study
organisms across natural barriers (e.g., Williams et al. 1988 ; Hallegraeff and Bolch
1992 ; Carlton and Geller 1993 ; Hay 1990 ; Gollasch 1996 ; Macdonald and Davidson
1998 ; Ruiz et al. 2000 ; Gollasch et al. 2000a , b , 2002 ; Olenin et al. 2000 ; Murphy
et al. 2002 ; David et al. 2007 ; Briski et al. 2010 , 2011 ). A summary of European
shipping studies revealed that 1,598 ballast water samples were collected between
1992 and 2003 on 565 vessels of different origin (see Table 1 ).
The diversity of living organisms (including native, cryptogenic and non-
indigenous species) found during the European BWS studies included viruses, bac-
teria including human pathogens, fungi, protozoa, algae (unicellular phytoplankton
algae and macroalgae), invertebrates and fi sh. Crustaceans, molluscs and poly-
chaetes, as well as algae, were the dominant groups found in samples and consisted
of more than 1,000 identifi ed species. The majority that occurred within ballast
were small in body dimensions and better able to survive the physical forces gener-
ated by the vessel pumps during the ballasting process. Nevertheless, fi shes of up to
15 cm have been found within tanks (Gollasch et al. 2002 ) which was also docu-
mented during BWS events when testing the performance of ballast water treatment
systems (Gollasch and David, own observation). A list of all animals, plants and
bacteria groups found in the European BWS studies undertaken until 2002 is avail-
able in Leppäkoski et al. ( 2002a , b ). Since this study was completed, further studies
were conducted (e.g., David et al. 2007 ; Drake et al. 2007 ; Dobbs 2008 ; McCollin
et al. 2008 ; Briski et al. 2010 , 2011 ) and altogether they provided suffi cient infor-
mation to support the need for ballast water management actions.
The majority of organisms taken-up in ballast water expire at an exponential rate
during the fi rst 3-5 days in a ballast tank due to a wide range of conditions that
occur within them (e.g., McCollin et al. 2008 ; Gollasch et al. 2000a , b ; Olenin et al.
2000 ). Ballast tanks are, for most organisms, unfavourable habitats, there is an