Cookies Policy

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies.

I accept this policy

Find out more here


No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.

Brill’s MyBook program is exclusively available on BrillOnline Books and Journals. Students and scholars affiliated with an institution that has purchased a Brill E-Book on the BrillOnline platform automatically have access to the MyBook option for the title(s) acquired by the Library. Brill MyBook is a print-on-demand paperback copy which is sold at a favorably uniform low price.

Access this article

+ Tax (if applicable)
Add to Favorites
You must be logged in to use this functionality

image of Journal of Crustacean Biology

ABSTRACT Five species of introduced planktonic copepods from Asia, including two species of the genus Pseudodiaptomus, have been reported from coastal bays of California. Recently we have found a third species of Pseudodiaptomus endemic to the Indo-Pacific, P. inopinus, to be established in the Columbia River estuary. Comprehensive studies of both pelagic and epibenthic zooplankton in the Columbia River estuary in 1979 and 1980 did not record P. inopinus (see Simenstad and Cordell, 1985; Jones et al., 1990). In September 1990, we sampled zooplankton at three depths across several tide cycles. These samples contained high densities and all life-history stages of P. inopinus. It now appears that this species has become established and is prominent in the estuarine turbidity maxima (ETM) region. Pseudodiaptomus inopinus cooccurs in the ETM region with extensive populations of the calanoid copepod Eurytemora affinis and the harpacticoid copepod Scottolana canadensis. Preliminary results suggest that the distribution and abundance of these three species vary in response to the physical processes of the ETM. These differences may reduce potential competitive interactions between the preexisting and exotic species. Introduction was probably via ballast water from ships arriving from Asia. However, the establishment of P. inopinus may have been encouraged by a synergism between increased ballast dumping, decrease in maximum flows due to regulation of the river, and the attenuation of extreme low temperatures in the estuary during the last decade.

Affiliations: 1: Wetlands Ecosystems Team, College of Ocean and Fishery Sciences, University of Washington, WH-10, Seattle, Washington 98195.


Full text loading...


Data & Media loading...

Article metrics loading...



Can't access your account?
  • Tools

  • Add to Favorites
  • Printable version
  • Email this page
  • Subscribe to ToC alert
  • Get permissions
  • Recommend to your library

    You must fill out fields marked with: *

    Librarian details
    Your details
    Why are you recommending this title?
    Select reason:
    Journal of Crustacean Biology — Recommend this title to your library
  • Export citations
  • Key

  • Full access
  • Open Access
  • Partial/No accessInformation