Pest Management (previously Pest Control)

March 5, 2022

Position statements developed by the CVMA reflect current knowledge regarding animal welfare. While they are not legislative, they do represent CVMA’s ongoing commitment to the advancement of animal welfare.

Position

The Canadian Veterinary Medical Association recognizes that lethal and non-lethal pest control measures may be employed against nuisance animals to reduce damage or conflict, promote sustainable agricultural production, control diseases, and/or to ensure the conservation of biodiversity. The CVMA holds that when control measures are deemed necessary, such measures must be humane, implementable, scientifically based, have minimal environmental or human health impacts, and abide by local legislative and municipal requirements. Consideration of the welfare implications on animals in conflict with humans is an important part of Integrated Pest Management (IPM).

Summary

  • The CVMA recognizes that some animals are considered to be nuisance animals or pests and their management may be deemed necessary.
  • When management procedures are needed, eco-system focused Integrated Pest Management programs are to be utilized which minimize risks to target and non-target species.
  • Non-lethal methods must be evaluated and implemented whenever possible but when lethal methods are used, the most humane method(s) must be selected.
  • The CVMA advocates for the development of species-specific national standards for humane pest control measures.
  • The CVMA supports further research and refinement into humane pest control measures.

Background

  1. The terms “pests” or “nuisance animals”, are used in regulations to describe overabundant or unwanted wildlife or feral animals, as well as invertebrate pests, which are subject to control measures to protect humans, animals, and/or the environment (One Health).
    • The Canadian Pest Control Products Act defines a “pest” as: an animal, a plant or other organism that is injurious, noxious, or troublesome, whether directly or indirectly, and an injurious, noxious, or troublesome condition or organic function of an animal, a plant or other organism (1).
    • Awareness and adherence to federal, provincial, and municipal laws are required when undertaking any control measures regarding nuisance animals.
  2. There is a growing global shift to consider the welfare implications of control measures on animals that are judged to be in conflict with human activities, or the environment, often referred to as pest or nuisance animals (2-10).
  3. Integrated Pest Management (IPM) programs are ecosystem-focused control strategies regarding the management or eradication of nuisance species (10-14). IPM elements are:
    • Proactive identification and prevention of potential pest problems.
    • Monitoring regional populations of animals and quantifying and assessing the detrimental impacts.
    • Establishing threshold levels for action.
    • Using strategies alone or in combination (including biological, physical, mechanical, cultural, behavioural, and chemical controls). The least harmful or toxic, most species-specific option should be chosen.
    • Ongoing evaluation and refinement of management strategies should be based on humane and ethical considerations, new research, technologies and societal expectations, health and safety considerations, environmental impact, and overall effectiveness.
  4. Whenever using pest control as part of IPM, the welfare implications, safety, and ecological impact (including impacts on non-target species) of the chosen strategy must be considered (3-16). (See also CVMA Position Statement on Trapping of Fur-Bearing Animals).
    • Non-lethal methods must be evaluated and implemented whenever possible.

      Examples of non-lethal pest control methods include:

      • elimination of food sources.
      • repellants and deterrents (harbourage1 removal, biological, chemical, physical).
      • pest species fertility control
      • wildlife vaccination (e.g., baits etc.).
      • planting decoy crops to protect target crops and
      • use of humane live traps with subsequent translocation and release where permitted.
    • When lethal methods are used, the most humane method(s) must be selected, and every effort must be made to minimize adverse ecological impact(s).

      The CVMA holds that when pests must be killed, the method chosen must be appropriate for the species, reliable, humane and must minimize fear, pain, and distress (see also CVMA Position Statement on Euthanasia)

    • Factors to consider with any method that may have a negative animal welfare or ecological impact on target and non-target species include: (1,10,12,15,16-25)

      • restraint/confinement times and harms from exposure or dehydration up to and including death,
      • pain, anxiety, fear, and/or distress,
      • long-term impact of injuries,
      • impacts on dependent offspring,
      • disease transmission to resident species,
      • long term survivability post translocation and release,
      • impacts on reproduction, immune function, overall health, and longevity.
  5. The CVMA strongly opposes the use of inhumane methods of pest control (4,5,8,13,16,17,18,19).
    • The CVMA encourages the use of pest control products that minimize animal suffering. Methods are considered inhumane if they:
      • cause a high level of pain or distress.
      • require a prolonged time to be effective.
      • result in significant negative health effects on individual animals that escape, or in non-target animals (8, 10, 13).
    • Several methods have been employed traditionally, however not all meet scientific criteria for humaneness e.g., strychnine and compound 1080 poisoning of large predators, denning2, rodenticides, glue traps (8,15,17,18).
  6. The CVMA advocates for the development of species-specific national standards for humane pest control measures.
  7. The CVMA supports further research and refinement into humane pest control measures that are grounded in sound animal science and ethics, are implementable and consider the principles of One Health.

References

  1. Government of Canada. Pest Control Products Act. Justice Laws Website. 2006. Available from: http://laws-lois.justice.gc.ca/eng/acts/P-9.01/page-1.html#h-1.
  2. Bracke MBM. Providing cross-species comparisons of animal welfare with a scientific basis. Njas-Wagen J Life Sc 2006; 54:61-75. Available from: https://www.tandfonline.com/doi/abs/10.1016/S1573-5214%2806%2980004-7
  3. Littin KE. Animal welfare and pest control: meeting both conservation and animal welfare goals. Anim Welfare. 2010; 19 (2):171-176. Available from: https://www.ingentaconnect.com/contentone/ufaw/aw/2010/00000019/00000002/art00006
  4. Littin, KE, Mellor, DJ. Strategic animal welfare issues: Ethical and animal welfare issues arising from the killing of wildlife for disease control and environmental reasons. Rev Sci Tech Off Int Epi 2005; 24:767-782. Available from: https://pubmed.ncbi.nlm.nih.gov/16358526/
  5. Littin KE, Mellor D, Warburton B, Eason CT. Animal welfare and ethical issues relevant to the humane control of vertebrate pests. N Z Vet J 2004; 52:1-10. Available from: https://www.tandfonline.com/doi/abs/10.1080/00480169.2004.36384
  6. Marks CA. Ethical issues in vertebrate pest control: Can we balance the welfare of individuals and ecosystems? In: Mellor DJ, Monamy V,eds. The Use of Wildlife in Research 1999:79-89.
  7. Mellor DJ, Littin KE. Using science to support ethical decisions promoting humane livestock slaughter and vertebrate pest control. Anim Welfare 2004;13:S127-132. Available from: https://www.ingentaconnect.com/content/ufaw/aw/2004/00000013/a00101s1/art00018
  8. Mason G, Littin KE. The humaneness of rodent pest control. Anim Welfare 2003; 12:1-37. Available from: https://www.researchgate.net/publication/253097632_The_humaneness_of_rodent_pest_control
  9. UFAW. Guiding Principles in the Humane Control of Rats and Mice. [Online]. Available from: https://www.ufaw.org.uk/downloads/welfare-downloads/guidance-on-humane-control-of-rodents-feb2509v19.pdf
  10. Dubois S, Fenwick N, Ryan E, Baker L, Baker S, Beausoleil N, Carter S, Cartwright B, Costa F, Draper C, Griffin J, Grogan A, Howald G, Jones B, Littin K, Lombard A, Mellor D, Ramp D, Schuppli C and Fraser D 2017a International consensus principles for ethical wildlife control. Conservation Biology : The Journal of the Society for Conservation Biology. Available from: https://www.wellbeingintlstudiesrepository.org/cgi/viewcontent.cgi?article=1000&context=ethcbio
  11. Government of British Columbia. Integrated Pest Management. Available from: https://www2.gov.bc.ca/gov/content/industry/agriculture-seafood/animals-and-crops/plant-health/integrated-pest-management
  12. Braysher M. Managing vertebrate pests: Principles and strategies. Bureau of Resource Sciences, Australian Government Printing Service. 1993:58pp.
  13. Sharp T, Saunders G. A model for assessing the relative humaneness of pest animal control methods. Australian Government Department of Agriculture, Fisheries and Forestry, Canberra, ACT. 2011. Available from: https://www.awe.gov.au/agriculture-land/animal/welfare/aaws/humaneness-of-pest-animal-control-methods
  14. Broom DM. The welfare of vertebrate pests in relation to their management. In: Cowan DP, Feare CJ, eds. Advances in Vertebrate Pest Management. Fürth: Filander Verlag, 1999:309-329.
  15. DEFRA (2005). Review of effectiveness, environmental impact, humaneness, and feasibility of lethal methods for badger control. A report to European Wildlife Division, Defra, 20 October 2005. Department for Environment, Food and Rural Affairs, UK, London, Available from: http://www.bovinetb.info/docs/Review-of-effectiveness-environmental-impact-humaneness-and-feasibility-of-lethal-methods-for-badger-control.pdf
  16. Schutz KE, Agren E, Amundin M, Röken B, Palme R, Mörner T. Behavioural and physiological responses of trap-induced stress in European badgers. J Wildl Manage. 2006; 70: 884-891. Available from: https://wildlife.onlinelibrary.wiley.com/doi/abs/10.2193/0022-541X(2006)70[884:BAPROT]2.0.CO;2
  17. Proulx G, Brook RK, Cattet M, Darimont C and Paquet PC 2015a Poisoning wolves with strychnine is unacceptable in experimental studies and conservation programmes. Environmental Conservation 43: 1–2. Available from: https://www.raincoast.org/wp-content/uploads/2015/07/Proulx-et-al_Poisoning-wolves-with-strychnine-is- unacceptable_EC_2015.pdf
  18. Sherley M. Is sodium fluoroacetate (1080) a humane poison? Anim Welfare 2007;16:449-458. Available from: https://ban1080.org.au/wp-content/uploads/2019/11/Sherley-Is-sodium-fluoroacetate-1080-a-humane-poison.pdf
  19. Iossa G, Soulsbury CD, Harris S. Mammal trapping: A review of animal welfare standards of killing and restraining traps. Anim Welfare 2007;16:335-352. Available from: https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.973.5675&rep=rep1&type=pdf
  20. O’Connor CE. Welfare assessment of vertebrate toxic agents. Surveillance 2004;31:19-20. Available from: https://www.sciquest.org.nz/browse/publications/article/47393
  21. White, PJ, Kreeger, TJ, Seal, US, et al. Pathological responses of red foxes to capture in box traps. J Wildl Manage 1991;55:75-80. Available from: https://www.jstor.org/stable/3809243
  22. Marks CA, Allen L, Gigliotti F, et al. Evaluation of the tranquilliser trap device (TTD) for improving the humaneness of dingo trapping. Anim Welfare 2004;13:393-399. Available from: https://www.researchgate.net/publication/233548803_Evaluation_of_the_trap_tranquiliser_device_TTD_for_improving_the_humaneness_of_dingo_trapping
  23. Morriss GA, Warburton B, Ruscoe WA. Comparison of the capture efficiency of a kill-trap set for brushtail possums that excludes ground-birds, and ground set leg-hold traps. New Zeal J of Zool 2000;27:201-206. Available from: https://www.tandfonline.com/doi/abs/10.1080/03014223.2000.9518227
  24. Warburton B, Gregory N G, Morriss G. Effect of jaw shape in kill-traps on time to loss of palpebral reflexes in brushtail possums. J Wildl Dis 2000;36:92-96. Available from: https://pubmed.ncbi.nlm.nih.gov/10682749/
  25. Woodroffe R, Bourne FJ, Cox DR, et al. Welfare of badgers (Meles meles) subjected to culling: Patterns of trap-related injury. Anim Welfare 2005;14:11-17. Available from: https://strathprints.strath.ac.uk/17300/

    1 Harbourage: in this context the word is used to describe a short- or longer-term shelter that is not considered a natural habitat for the species.

    2 Denning: in this context the term refers to the use of lethal methods of killing animals while they are found in dens.