Marine Biology

, Volume 121, Issue 2, pp 309–317 | Cite as

Adult rafting versus larval swimming: dispersal and recruitment of a botryllid ascidian on eelgrass

  • S. E. Worcester


The importance of larval dispersal in determining the distribution and abundance of benthic marine organisms is well recognized; however, the contribution of post-larval dispersal has not been measured. I compared the dispersal of swimming larvae with that of rafting colonies in a population of compound ascidians, Botrylloides sp., living attached to leaves of the eelgrass Zostera marina in Tomales Bay, California, USA in 1990–1992. Colonies rafting on broken eelgrass traveled over 200 times farther and had comparable recruitment success relative to swimming larvae. The recruitment of rafting colonies into new habitats was facilitated by the ability of thesecolonial animals to grow asexually onto surrounding substrata. Rafting colonies brooded larvae that were subsequently relased after the colony settled into a new habitat. These results suggest that colonization of new habitats can occur by post-larvae as well as larvae, and that long-range dispersal by species with short-lived larvae may occur by post-larval rafting.


Marine Organism Recruitment Success Larval Dispersal Swimming Larva Benthic Marine Organism 
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.


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Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • S. E. Worcester
    • 1
  1. 1.Department of Intergrative BiologyUniversity of CaliforniaBerkeleyUSA

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