Environmental factors influencing the dynamics of Chinese mitten crab zoeae in the San Francisco Bay-Delta

Steven Blumenshine,Deborah Rudnick,Ammon Rice,Brian Tsukimura

doi:10.3391/ai.2012.7.1.012

Steven Blumenshine, Deborah Rudnick + Show 2 more

Open Access

https://doi.org/10.3391/ai.2012.7.1.012

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Abstract

Abstract The Chinese mitten crab is an invasive catadromous species that has populated many European estuaries. However, despite repeated ‘introductions’, the only known established North American population is in the San Francisco Bay Delta, along with recent populations discovered in Chesapeake Bay and the Hudson River. In established populations, adult mitten crab numbers oscillate dramatically, and large numbers of crabs can have severe environmental impacts. Extremely little is known about the biology and ecology of juvenile stages, but understanding the factors behind new cohort survival is crucial for understanding the dynamics of newly-established populations. In this study, we use the only known long-term life-history data set to assess the relative importance of reproductive potential and environmental factors in regulating mitten crab population dynamics in San Francisco Bay. Both exploratory regression tree and bivariate data analyses support the hypotheses that concentrations of planktonic zoeae are strongly influenced by interactions between the number of breeding female crabs, the timing of reproduction, and water temperature. Additional studies are needed in other estuaries invaded by mitten crabs to test the generalities of these relationships and further evaluate the potential of these relationships to inform predictions about the extent and magnitude of mitten crab populations.

Highlights

IntroductionThe Chinese mitten crab, Eriocheir sinensis (H. Milne-Edwards, 1853), a catadromous brachyuran crab native to eastern China, has become widely established as an invasive species throughout Europe, in San Francisco Bay, USA since 1992 (Rudnick et al 2000), and more recently in the Chesapeake Bay and Hudson River in the eastern USA (Ruiz et al 2006; Schmidt et al 2009)
These impacts are exacerbated by the complex life history and highly variable population dynamics of the mitten crab
We focus on variation in the abundance of ovigerous adult females, and potential agents of zoeal mortality including freshwater discharge, predation, low salinity and temperature

Summary

Introduction

The Chinese mitten crab, Eriocheir sinensis (H. Milne-Edwards, 1853), a catadromous brachyuran crab native to eastern China, has become widely established as an invasive species throughout Europe, in San Francisco Bay, USA since 1992 (Rudnick et al 2000), and more recently in the Chesapeake Bay and Hudson River in the eastern USA (Ruiz et al 2006; Schmidt et al 2009). The mass migration of adult mitten crabs to their breeding grounds in San Francisco Bay has interfered with irrigation pumping systems and the protection and recovery of endangered and threatened fish species at fish recovery facilities (Siegfried 1999; Rudnick et al 2000; Rudnick et al 2005). These impacts are exacerbated by the complex life history and highly variable population dynamics of the mitten crab. The mitten crab’s complex catadromous life history makes it difficult to determine which aspects of the life cycle have the most influence on this species’ population dynamics

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