Reports of Prussian Carp in the Blindman and Medicine Rivers of Alberta

The invasive Prussian carp (Carassius gibelio) has been steadily expanding its range across Alberta's waterways since its initial detection in the province. Recent reports confirm the presence of this highly adaptable, self-cloning fish species in both the Blindman and Medicine Rivers, raising significant concerns for local aquatic ecosystems and water management. This report examines the current status of Prussian carp in these two river systems, the ecological impacts, and mitigation efforts underway.

Prussian Carp Invasion in Alberta: Background and Context

Prussian carp, native to central Europe and Asia, was first documented in Alberta in 2000, making it the first confirmed population in North America5. This invasive species has since spread to multiple watersheds across Alberta, including the Bow, Red Deer, North Saskatchewan, Oldman, Rosebud, and South Saskatchewan river systems10. The species has subsequently expanded into neighboring Saskatchewan through shared waterways10.

The Prussian carp possesses several biological characteristics that make it an exceptionally successful invader. Most notably, it can reproduce asexually through a process called gynogenesis, where females "steal" sperm from other fish species to trigger egg development without incorporating genetic material from the male12. This reproductive strategy allows them to rapidly clone themselves and establish dominant populations, with genetic analysis confirming that many Prussian carp in Alberta are genetically identical12.

Prussian Carp in the Blindman River

The Blindman River, a tributary of the Red Deer River system, has been confirmed as one of the waterways invaded by Prussian carp. According to reports, these invasive fish were first detected in the Red Deer River in 2017, subsequently spreading into the Blindman River system27.

The presence of Prussian carp in the Blindman River has created significant challenges for water management in the region. Of particular concern is Gull Lake, which historically relied on water pumped from the Blindman River to maintain water levels. However, in 2018, pumping operations ceased after Prussian carp were detected in the Blindman and Red Deer Rivers8. This cessation has contributed to Gull Lake's water levels dropping to their lowest point since 2004-06, affecting recreational activities and boat access8.

In response to this challenge, the Gull Lake Watershed Society has been exploring innovative solutions to prevent Prussian carp from entering the lake while resuming water pumping operations. They have developed and implemented an experimental filtration system using "geotubes," which consists of a fine membrane that traps carp eggs when water is pumped through it27. This filtration approach is considered a first-of-its-kind experiment for managing Prussian carp invasion7.

The society's efforts have shown promising results. According to Norval Horner, president of the Gull Lake Watershed Society, engineering consultants have reviewed their pressurized filtration system and declared it "100 percent successful" in capturing tiny carp eggs8. This success has led to conditional approval to restart the stabilization pumps, pending a new hydrology study and stakeholder consultation8.

Prussian Carp in the Medicine River

The Medicine River, which flows into the Red Deer River near Spruce View, has also been impacted by Prussian carp invasion. Recent water quality monitoring conducted between May and November 2023 at three locations along the river revealed that while the river is generally in good health, Prussian carp have established a presence in the system11.

Dana Kreil, a board member of the Medicine River Watershed Society (MRWS) and Lacombe County councillor, explicitly confirmed the presence of Prussian carp in the Medicine River, stating: "We have Prussian carp in there and they managed to live but we just want to make sure all fish can live in there"11. This statement came during discussions of water quality testing results that showed significant improvements in the river's overall health compared to 2007, when the river "failed everything" in terms of water quality metrics11.

The Medicine River is known for its fishing opportunities, with anglers targeting Northern pike, Walleye, and Lake whitefish9. The presence of Prussian carp potentially threatens these native fish populations and recreational fisheries.

Ecological Impacts of Prussian Carp in Alberta's Rivers

The invasion of Prussian carp has been associated with significant ecological disruptions across Alberta's waterways. Research conducted by the University of Alberta in the Red Deer River watershed has demonstrated that Prussian carp establishment causes measurable changes to fish communities and corresponding alterations in benthic invertebrate communities13. In some areas of Alberta, Prussian carp invasion has been associated with a decline of native fish species by up to 75%4.

Jonathan Ruppert, lead author of a study on Prussian carp impacts, explained: "Prussian carp decrease the abundance of native fish species and change aquatic invertebrate species (the bugs that live in the water). They disrupt the natural structure of these ecosystems"5. This disruption undermines fundamental processes that deliver clean water and healthy freshwater ecosystems5.

Several factors contribute to Prussian carp's competitive advantage over native species:

Survival in extreme environmental conditions, including low oxygen levels and high algae concentrations5
Rapid reproductive capabilities through gynogenesis, which also interferes with native species spawning5
Voracious plant consumption, depleting resources and forcing native species to compete for food and space12
Higher abundance in irrigation infrastructure than natural waterways, making these systems important vectors for further spread4

The invasion also creates socio-economic concerns, particularly for Alberta's $3.6 billion irrigation industry, as Prussian carp reduces water quality and has been found in higher concentrations in irrigation infrastructure4.

Management Approaches and Control Efforts

Managing Prussian carp invasion in Alberta's waterways presents significant challenges due to the species' reproductive capabilities and environmental tolerance. Current management approaches include:

Prevention and Monitoring

Alberta Environment and Parks emphasizes that "prevention is the best defence against Prussian carp as there are no selective control measures"10. The Alberta Conservation Association (ACA) has used environmental DNA (eDNA) sampling to determine the distribution of Prussian carp across the province, confirming their presence in the Bow, Red Deer, Oldman, and South Saskatchewan River drainages6.

Physical Removal

Direct removal of Prussian carp through netting and fishing has been attempted in several locations. At Blood Indian Park Reservoir, which once attracted anglers for its large trout, efforts by Alberta Environment and Parks (AEP) involved netting over 10,000 Prussian carp to reduce their populations. While these efforts showed some success, with reductions in small Prussian carp and rebounds in native Fathead minnow populations, physical removal methods are labor-intensive and may not be feasible for larger waterways10.

Regulatory Approaches

Alberta has implemented specific angling regulations for Prussian carp, requiring a sportfishing license but imposing no daily catch, possession or size limits10. Anglers are encouraged to practice a "Catch It, Kill It" approach, while ensuring proper disposal of dead fish10. Possession and transportation of live Prussian carp is illegal, and they cannot be used as bait10.

Innovative Solutions

The geotube filtration system developed by the Gull Lake Watershed Society represents an innovative approach to preventing Prussian carp from entering new waterways while allowing necessary water management activities to continue2 78. If proven successful in the long term, this technology could potentially be adapted for use in other threatened water bodies.

Conclusion

The presence of Prussian carp in the Blindman and Medicine Rivers represents part of a larger invasion pattern across Alberta's waterways that poses substantial ecological and economic threats. These invasions highlight the challenges of managing aquatic invasive species once they become established in interconnected river systems.

The documented cases in both rivers illustrate different stages of response: in the Blindman River, innovative filtration technology is being tested to prevent further spread while mitigating water level issues in Gull Lake; in the Medicine River, monitoring programs are tracking water quality while acknowledging the established presence of Prussian carp.

While complete eradication of Prussian carp from Alberta's rivers may not be feasible, continued monitoring, targeted removal efforts, angler education, and development of preventative technologies like the Gull Lake Watershed Society's filtration system represent important steps in managing this invasive species. Further research into selective control methods and continued public engagement will be essential components of long-term management strategies for this highly adaptable invasive species.

Citations:

Answer from Perplexity: pplx.ai/share

Alberta West News

CanadianPlanet

Welcome To Alberta West Online News

Blog Archive

About Me

Sunday, March 16, 2025