Letter to federal Ministers of Health and Agriculture and Agri-Food on the emergency registration of strychnine
April 22, 2026
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In response to the emergency registration of strychnine, AWA has written to the responsible federal ministers voicing our concerns and requesting that the ban of strychnine is upheld now and in the future.
AWA condemns the re-authorization of strychnine use, given the known environmental harms. Strychnine is a highly lethal neurotoxin, which indiscriminately kills many vertebrate species. It was used as a pesticide and predacide, but was banned for unacceptable environmental risks. The severe harm to non-target organisms, long-term effects on the ecosystem, and lack of evidence and public consultation in overturning the prior ban make this a poor solution to ground squirrel outbreaks.
The PDF letter is available here.
April 22, 2026
The Honourable Marjorie Michel, P.C., M.P.
Minister of Health
By email: hcminister.ministresc@hc-sc.gc.ca
The Honourable Heath MacDonald, P.C., M.P.
Minister of Agriculture and Agri-Food
By email: aafc.minister-ministre.aac@agr.gc.ca
Emergency registration of strychnine in Alberta and Saskatchewan
Alberta Wilderness Association (AWA) is writing regarding the emergency registration of strychnine announced March 30, 2026, and lasting until November 2027. While we acknowledge there are concerns around damage caused by ground squirrels, we strongly disagree with the use of strychnine, and given the proven environmental harm this toxin causes, condemn the decision to reauthorize its use.
Founded in 1965, AWA strives to help Albertans understand the intrinsic values that wildlife and wilderness provide and encourage communities to participate in conservation initiatives that will ensure a legacy for future generations. With over 10,000 members and supporters in Alberta and across Canada, AWA is dedicated to conserving Alberta’s wilderness and advocating for conservation strategies that protect Canada’s biodiversity.
Strychnine is a highly lethal neurotoxin that indiscriminately kills many vertebrate species. It acts primarily by inhibiting neurotransmitter action in the spinal cord, leading to painful seizures and eventually resulting in death. It was previously used in Canada as a pesticide and a predacide, before it was banned for unacceptable environmental risks. We argue this ban must be upheld, without exception, as historic use and scientific evidence have already proven the far-reaching and uncontainable harms of strychnine use on the ecosystem and on environmental health.
Regulatory review
Previous regulatory review by the Pest Management Regulatory Agency (PMRA) under Health Canada has determined that strychnine can cause severe and unintended damage to the environment. As outlined in the 2020 regulatory decision, “An evaluation of available scientific information has not shown that risks to the environment are acceptable when strychnine is used according to the current conditions of registration, or when additional mitigation is considered[1].” This was further supported by the re-evaluation of strychnine as a predacide in 2024, as “Health Canada scientists concluded that the continued registration of predacide uses of strychnine does not meet the requirements for protection of the environment.[2]”
Further, mitigation measures which have been attempted have been insufficient and unable to contain the toxin to target species or areas. Prior to its ban as a predacide, additional risk-reduction measures were considered, including establishing a “registrant-implemented product stewardship program,” instigating “updated and clarified reporting requirements” and additional guidelines on baiting, carcass removal, and site visits[3]. Despite these additional measures, “Health Canada found that there was more strychnine used than the number of poisoned carcasses retrieved. This means that there were strychnine-poisoned carcasses available in the environment for other animals to feed on which increases the risk of secondary poisoning.2” This suggests that additional measures were not able to prevent secondary poisoning and the toxin entering the food chain.
As stated in Health Canada’s decision on emergency use of strychnine, released February 6, 2026, “the PMRA determined that the information did not provide sufficient means to address the risks of concern identified in the re-evaluation that led to strychnine’s cancellation.[4]” The announcement further acknowledged that an emergency use request “can only be considered if there is evidence that the health and environmental risks are acceptable and the product has value in addressing the emergency pest situation.” Since this decision—dated less than two months before the approval of emergency strychnine use—there has not been evidence provided to adequately understand why the ban was overturned.
The decision to cancel strychnine use as both a pesticide and predacide was made after extensive review, including environmental risk assessments, incorporation of relevant studies, and a 90-day public comment period with clear responses by Health Canada to concerns. The recent decision to reauthorize strychnine was made without presenting additional evidence indicating a reduced environmental risk, and without broad public consultation. The collection and presentation of new evidence, as well as public consultation, must occur before decisions are made to allow strychnine to be used.
Non-target organism mortality
Strychnine has repeatedly been shown to harm non-target organisms. The compound is classified as toxic or highly toxic to birds and mammals. It has been recorded as a hazard to seed-eating birds[5], raptors[6], chipmunks, rabbits, mice and squirrels[7], as well as domestic animals and livestock. Between 1998 and 2013, there were recorded 93 cases of strychnine poisoning in dogs across western Canada[8]. An additional 38 cases of dog poisoning, as well as several horse and wildlife cases, were recorded from 2014 to 2023[9]. When used as a predacide, the non-target organisms recorded dead include foxes, coyotes, lynx, fishers, minks, martens, ermines, weasels, grizzly bears, skunks, ravens, eagles, crows and magpies, among other species 2,[10].
As mentioned in the Science Evaluation Update of the 2020 Re-evaluation decision, strychnine baiting of Richardson’s ground squirrel (RGS) burrows in accordance with label instructions and best management practices available, “results in the availability of poisoned RGS carcasses on the surface of treated sites.1” These poisoned carcasses are easily accessible to scavengers and predators, resulting in secondary poisoning of these species. Population models suggest strychnine use could significantly affect populations of predators such as snakes[11]. Smaller, sub-lethal doses were also indicated to impact behaviour and survival in great-horned owls and red-tailed hawks, both species which can prey on ground squirrels[12].
In addition, baits are occasionally consumed directly by non-target species. The Science Evaluation Update also notes, “A low percentage of treated burrows (8–15%) were reported to have bait ejected from them. As strychnine is a highly toxic substance, bait ejection, even at these levels, is considered to be an important route of primary exposure for non-target organisms.1” The presence of these baits can easily lead to primary poisoning of other species, such as deer mice, and increase the risk of secondary poisoning. Baits that attract ground squirrels have been found to be consumed by other non-target species as well[13].
There is little evidence to suggest mitigation measures are effective for reducing the risk of strychnine poisoning in non-target organisms. Health Canada’s announcement states that the current use “contains additional restrictions and mitigation measures to lower the environmental risk to an acceptable level.” However, few details have been provided regarding these additional measures or their efficacy. Previous product stewardship programs have proven unsuccessful. We request that any details of the new mitigation measures and scientific evidence indicating their effectiveness be provided publicly.
Reliance and ecosystem impacts
Agricultural pesticide application frequently creates a system of reliance, where more or stronger pesticides are necessary to achieve a similar result. This is largely due to resistance building up in the target organism, or—more common with a chemical such as strychnine—changes in the ecosystem which make continued pesticide use mandatory.
In the case of strychnine, the non-specificity means that use of this chemical will not only result in the loss of ground squirrels but could also result in the loss of predators. As these predators are normally responsible for control of ground squirrel populations, their loss results in fewer controls on future ground squirrel populations, increasing the likelihood of outbreaks or infestations. As a result, more strychnine would be required to control future populations, causing more ecological harm, as well as raising the price of production.
In addition, ground squirrels occupy an important niche in the ecosystem. They are common across the grasslands region, acting as prey for many species, such as hawks, eagles, owls, foxes, coyotes, badgers, and weasels. They are the primary prey species for ferruginous hawks, a species-at-risk in Canada[14]. They are also hunted and scavenged by burrowing owls and swift foxes; the 2012 recovery strategy for burrowing owls[15] and the 2009 assessment report on swift foxes[16] both acknowledge the threat posed by strychnine use for these species, directly and through the loss of their prey.
Ground squirrels also affect vegetation and soil health, creating new habitat for other species. The disturbance provided by their burrowing increases bare ground cover and shifts vegetation assemblages[17]. Their burrows also support soil aeration and water retention, improving soil health, and are also used by many other species, including badgers, foxes, snakes, and some bumblebees[18]. Although some control of ground squirrel populations may be required to support producers and ranchers, the loss of ground squirrels from the ecosystem would have devastating implications for many other species and for ecosystem health.
Human health
Strychnine poisoning in humans, although uncommon, has been documented. Cases of strychnine poisoning have included cases of children consuming dangerous products[19], among others[20]. There is no antidote for strychnine poisoning, and only symptoms can be treated. Poisoning can be fatal without immediate treatment.
Due to its toxicity, strychnine has been banned in several other countries, including members of the European Union, and its use is heavily restricted in the United States and Australia.
Long-term impacts and alternatives
Despite the limited time period approved for strychnine use, there will likely be long-term impacts. When the chemical was banned in 2020, it was phased out over a three-year period1. Similarly, the use of the predacide was phased out over 6 months2. Even after the pesticide was officially banned, several cases of strychnine poisoning in dogs were reported, suggesting its use even after the product was officially cancelled[21]. In addition, pesticide impacts on the ecosystem, especially on non-target organisms, are expected to last beyond the two years of approved application; in particular, the loss of predator populations can be slow to recover. Clearly, complete removal of strychnine and its disturbance from the environment can take some time.
Further, given that this emergency use decision was made without public consultation or clear evidence justifying reauthorization of a highly toxic compound, there are no safeguards against chemical use being extended, or against future reauthorizations. Extensive evidence and consultation were necessary in cancelling strychnine use, and reauthorizations should be held to an identical standard. Until mitigation measures taken to reduce strychnine impact on non-target organisms can be proven, the chemical should not be authorized for use.
There are alternatives to strychnine to control ground squirrel populations. In particular, ecological solutions help reduce the reliance on pesticides. For instance, predation was recorded as hugely impactful on arctic ground squirrel populations[22], and encouraging predator establishment helps prevent ground squirrel outbreaks. Nesting sites for raptors, tolerance from producers for foxes, coyotes, and badgers, and co-existing with other predators allows for natural controls of ground squirrels. Holistic management approaches, incorporating multiple approaches including crop diversification, habitat modification and fertilizer control, have proven effective at reducing pesticide use, and the corresponding harms to environmental and human health[23], with minimal economic impact[24].
Given the evidence presented in this letter, we strongly oppose the use of strychnine to control ground squirrel populations and urge for the ban to be re-enacted immediately and upheld without exemptions. Before any decision to reauthorize any pesticide with a known threat to the environment, there must be clear evidence presented, public consultation incorporated, and detailed use instructions provided.
Thank you for considering our comments. We look forward to your prompt response.
Sincerely,
ALBERTA WILDERNESS ASSOCIATION
Ruiping Luo
Conservation Specialist
Cc:
RJ Sigurdson, Minister of Agriculture and Irrigation, Government of Alberta (agric.minister@gov.ab.ca)
David Marit, Minister of Agriculture, Government of Saskatchewan (ag.minister@gov.sk.ca)
[1] Health Canada Pest Management Regulatory Agency. March 4, 2020. Strychnine and Its Associated End-use Products (Richardson’s Ground Squirrels): Final Decision. Retrieved April 20, 2026, from: https://publications.gc.ca/collections/collection_2020/sc-hc/h113-28/H113-28-2020-6-eng.pdf
[2] Health Canada Pest Management Regulatory Agency. March 7, 2024. Summary of RVD2024-04: Re-evaluation decision for predacide uses of strychnine and sodium monofluoroacetate and their associated end-use products. Retrieved April 20, 2026, from: https://www.canada.ca/en/health-canada/services/consumer-product-safety/reports-publications/pesticides-pest-management/decisions-updates/reevaluation-decision/2024/predacide-uses-strychnine-sodium-monofluoroacetate.html.
[3] Health Canada Pest Management Regulatory Agency. August 31, 2022. Predacide Uses of Strychnine and Sodium Monofluoroacetate and their Associated End-use Products: Consultation Document. Retrieved April 20, 2026, from: https://publications.gc.ca/collections/collection_2022/sc-hc/h113-27/H113-27-2022-18-eng.pdf.
[4] Health Canada Pest Management Regulatory Agency. February 6, 2026. Information Note – Strychnine emergency use request – Final decision. Retrieved April 20, 2026, from: https://www.canada.ca/en/health-canada/services/consumer-product-safety/reports-publications/pesticides-pest-management/fact-sheets-other-resources/information-note-strychnine-emergency-use-request-final-decision.html.
[5] Colvin, B. A., Hegdal, P. L., & Jackson, W. B. (1988). Review of non‐target hazards associated with rodenticide use in the USA 1. EPPO bulletin, 18(2), 301-308.
[6] Brown, P. R., & Lundie-Jenkins, G. (1999). Non-target mortalities during aerial strychnine baiting of house mice. Wildlife Research, 26(1), 117-128.
[7] Anthony, R. M., Evans, J., & Lindsey, G. D. (1986). Strychnine-salt blocks for controlling porcupines in pine forest: efficacy and hazards. In Proceedings of the Vertebrate Pest Conference (Vol. 12, No. 12).
[8] Cowan, V. E., & Blakley, B. R. (2015). A retrospective study of canine strychnine poisonings from 1998 to 2013 in Western Canada. The Canadian Veterinary Journal, 56(6), 587.
[9] Cowan, V. E. (2025). Strychnine poisoning in nontarget species in western Canada: a retrospective case series (2014 to 2023). The Canadian Veterinary Journal, 66(2), 168-176.
[10] Parr, S. (2023). An overview of known species killed during Alberta’s Gray Wolf (Canis lupus) strychnine program, 2005–2020. The Canadian Field-Naturalist, 137(3), 259-266.
[11] Bishop, C. A., Williams, K. E., Kirk, D. A., Nantel, P., Reed, E., & Elliott, J. E. (2016). A population model of the impact of a rodenticide containing strychnine on Great Basin Gophersnakes (Pituophis catenifer deserticola). Ecotoxicology, 25(7), 1390-1405.
[12] Cheney, C. D., Vander Wall, S. B., & Poehlmann, R. J. (1987). Effects of strychnine on the behavior of great horned owls and red-tailed hawks. Journal of Raptor Research, 21(3), 4.
[13] Proulx, G., MacKenzie, N., MacKenzie, K., Walsh, K., Proulx, B., & Stang, K. (2010). Strychnine for the control of Richardson’s ground squirrels: efficiency and selectivity issues. In Proceedings of the Vertebrate Pest Conference (Vol. 24, No. 24).
[14] Government of Canada. 2021. Ferruginous Hawk (Buteo regalis): COSEWIC assessment and status report. Retrieved April 20, 2026, from: https://www.canada.ca/en/environment-climate-change/services/species-risk-public-registry/cosewic-assessments-status-reports/ferruginous-hawk-2021.html
[15] Government of Canada. 2012. Burrowing Owl (Athene cunicularia): recovery strategy. Retrieved April 20, 2026, from: https://www.canada.ca/en/environment-climate-change/services/species-risk-public-registry/recovery-strategies/burrowing-owl-2012.html.
[16] Government of Canada. 2009. COSEWIC assessment and status report on the Swift Fox (Vulpes velox) in Canada. https://wildlife-species.canada.ca/species-risk-registry/virtual_sara/files/cosewic/sr_Swift%20Fox_0810_e.pdf.
[17] Newediuk, L. J., & Hare, J. F. (2020). Burrowing Richardson’s ground squirrels affect plant seedling assemblages via environmental but not seed bank changes. Current Zoology, 66(3), 219-226.
[18] MultiSAR. 2020. Burrowing Animals. Retrieved April 20, 2026, from: https://multisar.ca/wp-content/uploads/2015/10/Burrowing-Animals.pdf.
[19] Symons, A. J. C., & Boyle, A. K. (1963). Accidental strychnine poisoning: a case report. BJA: British Journal of Anaesthesia, 35(1), 54-56.
[20] Parker, A. J., Lee, J. B., Redman, J., & Jolliffe, L. (2011). Strychnine poisoning: gone but not forgotten. Emergency Medicine Journal, 28(1), 84-84.
[21] Levy, B. April 4, 2024. Veterinarian warns strychnine still out there, despite Saskatchewan ban (Saskatoon StarPhoenix). Retrieved April 20, 2026, from: https://thestarphoenix.com/news/local-news/veterinarian-warns-strychnine-still-out-there-despite-saskatchewan-ban.
[22] Byrom, A. E., Karels, T. J., Krebs, C. J., & Boonstra, R. (2000). Experimental manipulation of predation and food supply of arctic ground squirrels in the boreal forest. Canadian Journal of Zoology, 78(8), 1309-1319.
[23] Nandillon, R., Guinet, M., & Munier-Jolain, N. (2024). Crop management strategy redesign enables a reduction in reliance on pesticides: A diachronic approach based on a diversity of French commercial farms. Agriculture, Ecosystems & Environment, 366, 108949.
[24] Romain, N., Maé, G., & Nicolas, M. J. (2026). Reducing pesticide use through the adaptation of crop management strategies has little impact on farm economic performance. European Journal of Agronomy, 175, 128030.