Environmental Biology of Fishes

, Volume 85, Issue 1, pp 51–59 | Cite as

Salinity tolerance of non-native Asian swamp eels (Teleostei: Synbranchidae) in Florida, USA: comparison of three populations and implications for dispersal



Three populations of non-native Asian swamp eels are established in peninsular Florida (USA), and comprise two different genetic lineages. To assess potential for these fish to penetrate estuarine habitats or use coastal waters as dispersal routes, we determined their salinity tolerances. Swamp eels from the three Florida populations were tested by gradual (chronic) salinity increases; additionally, individuals from the Miami population were tested by abrupt (acute) salinity increases. Results showed significant tolerance by all populations to mesohaline waters: Mean survival time at 14 ppt was 63 days. The Homestead population, a genetically distinct lineage, exhibited greater tolerance to higher salinity than Tampa and Miami populations. Acute experiments indicated that swamp eels were capable of tolerating abrupt shifts from 0 to 16 ppt, with little mortality over 10 days. The broad salinity tolerance demonstrated by these experiments provides evidence that swamp eels are physiologically capable of infiltrating estuarine environments and using coastal waters to invade new freshwater systems.


Ecophysiology Monopterus Nonindigenous species Osmoregulation Synbranchidae 



Special thanks to Mary E. Brown, Travis Tuten and Eddie E. Leonard for assistance in the lab and field. Assistance in the field was also provided by Shane Ruessler and Carla Wieser. We are also grateful to Rob Bennetts and Howard Jelks for statistical advice and to William F. Loftus, Mark Peterson and two anonymous reviewers for comments on drafts of the manuscript. Sherry Bostick and Denise Gregoire contributed with final formatting of the manuscript. Funding was provided to LGN as part of U.S. Geological Survey project number 01-FH-01. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.


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Copyright information

© US Government 2009

Authors and Affiliations

  1. 1.U.S. Geological SurveyFlorida Integrated Science CenterGainesvilleUSA

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