Aquatic Invasive Species in Nova Scotia

Vase Tunicates

European Green Crab

Goldfish

Red Swamp Crayfish

This page is specific to aquatic invasive species in Nova Scotia. For more general information about what aquatic invasive species are, how they spread and their impacts, visit ‘About aquatic invasive species’ on our national website.

DFO Maritimes Region is responsible for aquatic invasive species in freshwater and the surrounding coastal areas of Nova Scotia. The management of aquatic invasive species in Nova Scotia is a shared responsibility between the federal and provincial governments.

List of aquatic invasive species in Nova Scotia

Interested in learning more about the aquatic invasive species (AIS) present in the Maritimes Region? Check out this list of AIS in freshwater and marine areas of Nova Scotia.

Preventing aquatic invasive species

We’re working to prevent the introduction and spread of aquatic invasive species in Canada. Learn what we’re doing and how you can help.

Reporting an aquatic invasive species 

If you think you’ve discovered an aquatic invasive species:

1. take photos
2. note :
   • the exact location (GPS coordinates)
   • the observation date
   • identifying features
3. contact us (Maritimes) to report it

Learn more

Review information and resources about aquatic invasive species found in the Maritimes Region.

Recent scientific publications

• Morrison MK, KHowland K, Grey EK, Barrett TJ, DiBacco C, McBride MC, Sevellec M, Lacoursiere-Roussel A. 2026. The Seasonal Rhythms of Coastal eDNA: Insights Into Biodiversity and Regional Detection Patterns. Environmental DNA8, no. 1: e70236. (English only)
• Poirier LA, Pratt CJ, Hope E, Kingsbury S, McAlpine DF, LeBlanc F, Burbidge C. 2026. First record of the nonindigenous crayfish, Procambarus virginalis Lyko, 2017, in Nova Scotia, Canada. BioInvasions Records 15 (in press) (English only)

• Hill JM, Simard M, Weise AM, Hubbard J, Kingsbury S. 2025. National Screening Level Risk Assessment (SLRA) of Goldfish, Prussian Carp, Chain Pickerel, and Black Crappie in Canada. DFO Can. Sci. Advis. Sec. Res. Doc. 2025/023. ix + 90 p. (English only)

• Kingsbury S,  Weise AM, Guerin A, Spearin B, Burbidge C, Plourde M-C. 2025. March of the Mussel: Is Atlantic Canada at risk of zebra mussel (Dreissena polymorpha) invasion?. Canadian Journal of Fisheries and Aquatic Sciences. 82: 1-14. (English only)

• Pratt CJ, Trott TJ, Bernier RY, Boerder K, Goodwin C, Barrell J, Gregoire B, Rawlings TA, Cronmiller E, Ma KCK, Sargent PS, McBride MC, DiBacco C, Hiltz C, Kingsbury S. 2025. The overlooked introduction of the encrusting bryozoan Juxtacribrilina mutabilis to eastern Canada. Journal of the Marine Biological Association of the United Kingdom, 105, e98. (English only)

• Pratt CJ, Ashworth EC, DiBacco C, Kingsbury S. 2025. Balancing efficiency and rigour in horizon scanning: an application to the management of invasive non-indigenous species in the marine waters of Eastern Canada. Management of Biological Invasions 16(3): 749–785. (English only)

• Kingsbury S, Poirier LA, Aucoin R, Shaw-McDonald S, Engelstad PS, Therriault TW, Wilcox M. 2025. A Horizon Scan watchlist of freshwater non-indigenous species in the maritime provinces of Canada. Management of Biological Invasions 16(3): 699–723. (English only)

• Kingsbury S, Collison BR, Daigle R, Hogan JD, Lowen B, Lowles AG, Stortini C, Trudel M, Tuziak SM. 2024. A new tool for setting biodiversity management priorities adapted from aquatic invasive species management: A pilot using Atlantic salmon (Salmo salar) in NS, Canada. Ecological Solutions and Evidence. 5(2):e12340. (English only)
• Pratt C, Poirier L, Bond M, Campbell L, Kingsbury S, Burbidge C, Hominick C. 2024. First record of the non-indigenous crayfish, Procambarus clarkii (Girard, 1852), in Nova Scotia, Canada. BioInvasions Records. 13(3):815–824. (English only)
• Brooks CM, Krumhansl K. 2023. First record of the Asian Antithamnion sparsum Tokida, 1932 (Ceramiales, Rhodophyta) in Nova Scotia, Canada. BioInvasions Records. 12(3):745–752. (English only)
• Lowen J, DiBacco C. 2022. Range expansion and establishment of a non-indigenous tunicate (Diplosoma listerianum) in thermal refugia is mediated by environmental variability in changing coastal environments. Canadian Journal of Fisheries and Aquatic Sciences. 80(2):330–345. (English only)
• LeBlanc F, Belliveau V, Watson E, Coomber C, Simard N, DiBacco C, Bernier R, Gagné N. 2020. Environmental DNA (eDNA) detection of marine aquatic invasive species (AIS) in Eastern Canada using a targeted species-specific qPCR approach. Management of Biological Invasions. 11(2):201-217. (English only)
• Lyons DA, Lowen JB, Therriault TW, Brickman D, Guo L, Moore AM, Peña MA, Wang Z, DiBacco C. 2020. Identifying marine invasion hotspots using stacked species distribution models. Biological Invasions. 22(11):3403–3423. (English only)