Species Information

Spiny water fleas (Bythotrephes longimanus) Spiny water fleas (Bythotrephes longimanus)
Emily DeBolt, Lake George Association
Spiny water fleas (Bythotrephes longimanus)
Emily DeBolt, Lake George Association
Spiny water flea
Bythotrephes longimanus

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History
  • Spiny water flea was first found in North America in 1984 in Lake Huron

Characteristics
  • Small predatory crustacean
  • Grows up to 0.6 in (15 mm) long
  • Long, straight tail spine is twice as long as body

Habitat
  • Estuaries, lakes, wetlands
  • Upper water column of large and small temperate lakes
  • Can tolerate brackish water
  • Limited to regions where water temperature is 40-86 degrees F and salinity is 0.04-8.0%

Known Distribution in the Northeast
  • New York and Great Lakes region
  • 2014 discovered in Lake Champlain (NY & VT)
  • Native to Europe and Asia

Impacts
  • Competes directly for prey with juvenile and small fish; implicated as a factor in decline of alewife
  • Substantial impact on zooplankton community structure
  • Can foul fishing lines and downrigger cables

Spiny water fleas on fish line
Emily DeBolt, Lake George Association
Spiny water flea (Bythotrephes longimanus)
Dave Brenner, Michigan Sea Grant College Program