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Research Technical Report

Undoing the Undaria: An Assessment of Management Strategies for the Invasive Species Undaria Pinnatifida in Monterey Bay Harbor

Korabik, A.R., and S. Lonhart (November 2016)

Poster presentation at the Western Society of Naturalists Annual Meeting, November 10-13, 2016, Monterey, CA


Undaria pinnatifida (Harvey) Suringar (Laminariales, Phaeophyceae), a brown algae native to Northeast Asia, has been present in Monterey Harbor since 2001, when it was first found on the floating docks of A Tier. Undaria has become a problem across the world since the 1980s, having established colonies in multiple locations, including the Mediterranean Region, Australia, New Zealand, Tasmania, and Argentina. In this project, we seek to examine improved methods of removal that may reduce the time and effort required to manage the Undaria population of Monterey Harbor. We conducted an experiment in Monterey Harbor during the months of June and July to measure growth rates of Undaria individuals under two different treatments. Five sets of individuals from three age classes (young, juvenile, and mature) were cut in half either above or below the meristem, and were consequently measured twice a week for the duration of the experiment. Results show that Undaria growth is arrested in portions separated from the meristem, while portions with the meristem still intact are able to proceed to reproductive maturity.