Potential microbial bioinvasions via ships' ballast water, sediment, and biofilm

Pergamon-Elsevier Science LTD
Publication Type:
Journal Article
Marine Pollution Bulletin, 2007, 55 (7-9), pp. 333 - 341
Issue Date:
Full metadata record
Files in This Item:
Filename Description Size
Thumbnail2006007044.pdf691.02 kB
Adobe PDF
A prominent vector of aquatic invasive species to coastal regions is the discharge of water, sediments and biofilm from ships' ballast-water tanks. During eight years of studying ships arriving to the lower Chesapeake Bay, we developed an undertsnading of th mechanisms by which invasive microorganisms might arrive to the region via ships. Within a given ship, habitats included ballast water, unpumpable water and sediment (collectively known as residuals) and biofilms formed on internal surfaces of ballast-water tanks. We sampled 69 vessels arriving from foreign and domestic ports, largely from Western Europe and Mediterranean region and the US East and Gulf coasts. All habitats contained bacteria and viruses. By extrapolating the measured concentration of a microbial metric to the estimated volume of ballast water, biofilm or residual sediment and water within an average vessel, we calculated the potential total number of microorganisms contained by each habitat, thus creating a hierarchy of risk of delivery. The estimated concentration of microorganisms was greatest in ballast water >> sediment and water residuals >> biofilms. From these results, it is clear microorganisms may be transported within ships ina varierty of ways. Using temperature tolerence as a measure of survivability and the temperature difference between ballst-water samples and the water into which the ballast water was discharged, we estimated 56% of microorganisms could survive in the lower Bay. Extrapolated delivery and survival of microorganisms to thePort of Hampton Roads in lower Chesapeake Bay shows on the order of 10 20 microorganisms are discharged annually into the region.
Please use this identifier to cite or link to this item: