Marine Biology

, Volume 156, Issue 1, pp 39–53 | Cite as

Differences in morphology and habitat use among the native mussel Mytilus trossulus, the non-native M. galloprovincialis, and their hybrids in Puget Sound, Washington

  • Joel ElliottEmail author
  • Kathleen Holmes
  • Rachel Chambers
  • Kate Leon
  • Peter Wimberger
Original Paper


Mytilus galloprovincialis (Mg), the Mediterranean blue mussel, is sympatric with the native M. trossulus (Mt) throughout much of the north Pacific, likely as the result of human introduction. We investigated the distribution of the two species and their hybrids (Mgt) in Puget Sound, Washington, to determine whether differences occur in habitat preference between the two species and hybrids. In addition, we investigated whether there were consistent size and shape differences between the native and introduced mussels and hybrids. Measurements of over 6,000 mussels from 30 sites, of which 1,460 were genotyped for a species-specific genetic marker, revealed that Mg and Mgt can be found throughout Puget Sound. Mg and Mgt were larger and exhibited a greater height:length ratio than Mt. Frequencies of Mg and Mgt were higher in subtidal habitats, such as docks, than on intertidal rocks, walls or pilings. Within intertidal habitats, Mg and Mgt were more frequent than Mt in the lower reaches of the intertidal. At slightly more than half the sites the frequency of the three genotypes accorded with random mating expectations suggesting no consistent barriers to gene flow between species. The standardized random sampling methods and simple morphometric identification techniques described here can be used to test whether the frequency of invasive mussels changes over time and space in Puget Sound.


Genotype Frequency Dock Random Mating Intertidal Zone Pacific Coast 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Many thanks to the University of Puget Sound Summer Research Committee and the University Enrichment Committee for financial assistance for this research, G. King and J. Davis at Taylor Shellfish Farms for supplying Mt and Mg mussels and information, M. Morrison, L. Rudensey, E. Young, J. Garamella, K. Haley, R. Coon, and all of the others who have helped us in numerous ways with this research. We thank J.P.A. Gardner and A. Wood for insightful comments on the manuscript and Victoria University, Wellington for space and hospitality to PHW. The methods of the study comply with the current laws of Washington State and the USA.


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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Joel Elliott
    • 1
    • 2
    Email author
  • Kathleen Holmes
    • 1
  • Rachel Chambers
    • 1
  • Kate Leon
    • 1
  • Peter Wimberger
    • 1
  1. 1.Department of BiologyUniversity of Puget SoundTacomaUSA
  2. 2.Department of BiologyUniversity of Puget SoundTacomaUSA

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