Modeling ships' ballast water as invasion threats to the Great Lakes.

• Author(s) / Creator(s)

  • MacIsaac, H.J.
  • Lewis, Mark A.
  • Robbins, T.C.

• The spread of nonindigenous species in aquatic ecosystems provides an opportunity to develop new perspectives on the invasion process. In this paper we review existing invasion models, most of which were developed to describe invasions of terrestrial habitats, and propose an alternative that explores long-distance invasions mediated by discharge of contaminated ballast water by ships in-bound to the Great Lakes. Based on current knowledge of shipping traffic to the Great Lakes, our model predicts that mid-ocean exchange of ballast water lowers propagule delivery by approximately three to four orders of magnitude relative to unexchanged ballast water. Propagule pressure of individual ships that enter the Great Lakes loaded with cargo and which declare 'no ballast on board' (NOBOB) is typically one to two orders of magnitude higher than that of vessels that exchange ballast. Because NOBOB vessels dominate (~90%) inbound traffic into the Great Lakes, these vessels collectively appear to pose the greatest risk of new introductions mediated via ballast water.

• Date created

  2002-01-01

• Subjects / Keywords

  • Exotic species
  • Invasion modeling
  • Spatial dynamics
  • Dispersal
  • Ballast water
  • Species invasions
  • Great Lakes

• Type of Item

  Article (Published)

• DOI

  https://doi.org/10.7939/R37M04129

• License

  © 2002 NRC Research. This version of this article is open access and can be downloaded and shared. The original author(s) and source must be cited.