News & Updates

Spiny Waterflea

Aquatic invasive species discovered in Algonquin Park

Algonquin Park staff have continued to sample additional lakes following the discovery of this aquatic invasive species in Kioshkokwi Lake, Manitou Lake, and North Tea Lake last fall. Spiny Waterflea were also recently detected in four additional lakes: Three Mile Lake, Mink Lake, and Cauchon Lake in the northwest and Rock Lake south of Hwy 60.

Native to Europe and Asia, the spiny waterflea is a freshwater zooplankton that can outcompete native zooplankton species and drastically disrupt aquatic food webs. This can lead to decreased food sources for native fish species as small or young fish cannot consume them due to their sharp, barbed bodies. Spiny waterflea can also pose negative impacts to anglers due to their ability to form sticky masses when they group together which can clog fishing rod eyelets and other angling gear

Spiny waterflea reproduce very quickly and there are currently no known methods of removing the species once it is detected in a waterbody. Boaters and anglers are considered a primary pathway of spread as spiny waterflea and their eggs can be inadvertently moved in residual water in boats or gear and on fishing line, bait buckets, livewells, or fishing nets. Ontario Parks is currently working on outreach messaging for Algonquin Park users that outlines the threats of this invasive species and ways to help stop the spread.

Best practices to help stop the spread:

  • When fishing in infested lakes, anglers are encouraged to wipe down their line as they reel it in from their final cast of the day or as they reel in their downrigger line and cable.
  • Inspect boats, trailers, and equipment after each use. Remove all plants, animals, and mud before moving to a new waterbody.
  • Drain water from motors, live wells, bilges and transom wells while on land.
  • Rinse all equipment with high pressure (>250 psi) or hot (50°C / 122°F) water OR let it dry in the sun for at least six hours (ideally, five days) before moving to another waterbody.

If you see an invasive waterflea or other invasive species in the wild, please contact the toll-free Invading Species Hotline at 1-800-563-7711, or visit to report your sighting.

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