Meeting Abstract

P1-55   -   Evidence for the Resurgence of the Chinese Mitten Crab, Eriorcheir sinensis, in the San Francisco Bay Estrada Caballero, M*; Tsukimura, B; California State University, Fresno; California State University, Fresno miguel.estrada@mail.fresnostate.edu

In 1992, the Chinese mitten crab, Eriocheir sinensis, was discovered in the San Francisco Bay Delta system due to human introduction. Since the establishment of this invasive species, there have been many negative environmental and economic impacts surrounding the San Francisco Bay. Explosions in adult populations can potentially have negative effects on native species through competition and predation. Other effects of the mitten crab are caused by juveniles that include stream bank and levee erosion through burrowing behavior that could potentially destroy future housing developments and erode natural ecosystems. Monthly plankton tows taken from the California Department of Fish and Wildlife (CDFW) station D41 were analyzed for E. sinensis zoeae. Brachyuran zoeae and megalopa were keyed to species with the use of a dichotomous key (Rice and Tsukimura, 2007; Gonzales et al, 2009). In April 2003, was the highest number of mitten crab zoeae where they recorded a total of 407 larva samples (CPUE = 4064.5). In 2005, no adult crabs were found in Otter trawls conducted by the CDFW and by 2008, no mitten crab zoeae were found in plankton tow surveys. However, in 2012 a total of 26 mitten crab megalopa were discovered and in 2013, another 9 mitten crab megalopa were found. This could be the beginning of the population resurgence for the Chinese Mitten Crab since their population dynamics are known to undergo dramatic oscillation patterns. If population explosions can be predicted, preparations can be made for the negative effects caused by the downstream migration of mitten crab juveniles.