Aquatic Invasive Species

CARP is excited to be coordinating a highly collaborative project focused on addressing the threat of aquatic alien invasive species (AIS) to our native fish, including species at risk such as the Atlantic Salmon and Atlantic Whitefish. This work is supported through the Canada Nature Fund for Aquatic Species and Aquatic Habitat. 

Some of the key partners on this project include:

Nova Scotia Department of Fisheries and Aquaculture

Coastal Action 

Mersey Tobeatic Research Institute

Nova Scotia Salmon Association

NSLC Adopt A Stream

Mi’kmaq Conservation Group

LaHave Salmon Association

Nova Scotia Power


Project News and Updates:


Help us pilot a new citizien science monitoring program by becoming a volunteer angler. Complete the citizen science monitoring program pre-registration survey 


Share your knowledge of aquatic alien invasive species distribution and help us understand awareness about the threat of AIS by completing the angler survey

Project Activities:


  • Delivering education and outreach programs to raise awareness about the threat of aquatic AIS and improve compliance with regulations and best practices that help reduce the spread of AIS  


  • Delivering outreach events and activities that raise public awareness about aquatic species at risk (SAR) and help community members understand how they can help mitigate threats to these species


  • Developing and piloting a citizen science monitoring program that can be used for early detection and to monitor the spread of AIS


  • Working with partners across the province to ensure access to up-to-date geospatial data about AIS observations for use in project planning and other management activities


  • Filling data gaps about the current distribution of AIS through field sampling

  • Coordinating the development of an aquatic habitat connectivity planning tool that considers how restoration actions might facilitate the spread of AIS. Resource materials will be developed so that conservation organizations across the province can be trained to factor the threat of AIS into planning for future restoration projects

In September 2020 the CARP team hosted an "East Your Invasive" event in the Town of Annapolis Royal. Participants were able to sample a chowder featuring smallmouth bass and chain pickerel. 

Stay tuned for more event dates, to be announced this spring!

This fall 9 new interpretive signs were installed at popular angling locations across the province to raise awareness about the threats associated with chain pickerel and smallmouth bass. 

What are alien invasive species (AIS)? 

Text from NS Department of Fisheries and Aquaculture

An invasive alien species is one introduced outside its normal distribution, whose establishment and spread can affect ecosystems, habitats, or other species.

The two aquatic AIS in freshwater ecosystems of greatest concern in Nova Scotia are the Chain Pickerel (Esox niger) and Smallmouth Bass (Micropterus dolomieu).

Smallmouth Bass were legally introduced to a handful of Nova Scotian lakes in the 1940s; since then, they have spread into at least 188 lakes and rivers. Chain Pickerel  were illegally introduced into three lakes in 1945 and are now in at least 95 lakes. Both have spread either through further intentional introduction between watersheds or via natural dispersal within watersheds. Smallmouth bass and chain pickerel transform freshwater ecosystems by occupying the niche of top fish predator. Although smallmouth bass is a favourite of anglers, it directly consumes small-bodied fish or out-competes them for food. Chain pickerel and smallmouth bass rapidly displace native speckled trout (Salvelinus fontinalis), along with other species favoured by sport fishers. Chain pickerel is a voracious predator, and few soft-bodied fish can coexist with this species. Besides its effect on fish populations, the ecological changes caused by chain pickerel could negatively impact birds and mammals, such as mergansers, cormorants, kingfishers, eagles, mink, and otter.

Despite stewardship and education, smallmouth bass and chain pickerel continue to spread through illegal transfers between watersheds.

Chain pickerel and Atlantic Whitefish.

In 2013, Chain Pickerel were detected in the Petite Rivière Lakes, which contain the only population of Atlantic Whitefish (Coregonus huntsmani) in the world. An emergency mitigation strategy was proposed soon after the discovery, and actions are being taken by governmental and non-governmental organizations to further protect the endangered Atlantic whitefish.

Chain Pickerel

(Esox niger)

Smallmouth Bass

(Micropterus dolomieu)

Top: adult, Bottom: juvenile

Atlantic Whitefish

(Coregonus huntsmani)

"The Atlantic whitefish (Coregonus huntsmani) is the evolutionary foundation of all whitefish species  in North America and is a unique and important part of Canadian biodiversity.  In 1984, the Atlantic whitefish became the first species in Canada to be declared endangered and remains on the brink of extinction today.  Unfortunately, this species that once hosted both a commercial and recreational fishery has been reduced to a single population  struggling for survival in three small interconnected lakes in southwestern Nova Scotia."

Learn more by exploring Coastal Action's Atlantic Whitefish Story Map