In situ hatching of invertebrate diapausing eggs from ships’ ballast sediment

Authors

  • Sarah A. Bailey,

    Corresponding author
    1. Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, N9B 3P4, Canada,
      Correspondence: Sarah A. Bailey, Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, N9B 3P4, Canada. Tel.: (519) 253-3000 ext 2734, Fax: (519) 971-3616, E-mail: sarahbailey@canada.com
    Search for more papers by this author
  • Kanavillil Nandakumar,

    1. Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, N9B 3P4, Canada,
    Search for more papers by this author
    • Present address: Biology Department, Lakehead University, Thunder Bay, ON, P7B 5E1, Canada.

  • Ian C. Duggan,

    1. Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, N9B 3P4, Canada,
    Search for more papers by this author
    • Present address: Centre for Biodiversity and Ecology Research, Department of Biological Sciences, University of Waikato, Hamilton, New Zealand.

  • Colin D. A. Van Overdijk,

    1. Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, N9B 3P4, Canada,
    Search for more papers by this author
  • Thomas H. Johengen,

    1. Cooperative Institute for Limnology and Ecosystems Research/University of Michigan, Ann Arbor, MI, 48104-2298, USA; and
    Search for more papers by this author
  • David F. Reid,

    1. National Oceanic and Atmospheric Administration/Great Lakes Environmental Research Laboratory, Ann Arbor, MI, 48105-2945, USA
    Search for more papers by this author
  • Hugh J. MacIsaac

    1. Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, N9B 3P4, Canada,
    Search for more papers by this author

Correspondence: Sarah A. Bailey, Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, N9B 3P4, Canada. Tel.: (519) 253-3000 ext 2734, Fax: (519) 971-3616, E-mail: sarahbailey@canada.com

ABSTRACT

Ships that enter the Great Lakes laden with cargo carry only residual ballast water and sediment in ballast tanks. These ships are designated ‘no ballast on board’ (NOBOB) and constitute > 90% of inbound traffic. We conducted in situ experiments using emergence traps to assess the viability and the introduction potential of invertebrate diapausing stages present in ships’ ballast sediment. All trials commenced while vessels operated on the lower lakes (Erie, Ontario) and were completed 6–11 days later at ports on the upper lakes (Michigan, Lake Superior). Eight trials were conducted on four ships using five different ballast sediments. Hatching was observed on every ship, although not from all sediments on all ships. Overall hatch rates were very low (0.5 individuals per 500 g sediment), typically involving activation of < 0.05% of total eggs present. Five species of rotifers and copepod nauplii were hatched from ballast sediments, although only one or two species typically hatched from any one sediment. Results of this study indicate that hatching of diapausing eggs contained in ballast sediment of NOBOB ships poses a relatively low risk of invasion to the Great Lakes. However, as reproduction may occur in tanks, and non-indigenous species may be involved in numerous introduction events, the risk posed by this vector is small but potentially important. While dormancy is a characteristic enabling enhanced survival during transportation in ballast tanks, it becomes a hindrance for introduction.

Ancillary