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Spiny waterflea  (Not seen 0n Gull Chain yet)

(Bythotrephes longimanus)

From the Minnesota DNR website:


On a fishing line, spiny water fleas look
like bristly gobs of jelly with black spots.

Adult size of the spiny water flea is 3/8 inch.

Species and Origin: Spiny waterfleas are zooplankton (microscopic animals). Native to Europe and Asia, they were introduced into the Great Lakes by ballast water discharged from ocean-going ships. They were first discovered in Lake Ontario in 1982 and spread to Lake Superior in 1987. Adults range from 1/4 to 5/8 inch long. Spiny waterflea have a single long tail with small spines along its length.

Impacts: Spiny waterfleas eat small animals (zooplankton), including Daphnia, which are an important food for native fishes. In some lakes, they caused the decline or elimination of some species of native zooplankton. They can clog eyelets of fishing rods and prevent fish from being landed.


More information:

Minnesota Sea Grant (U of M)

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