The position of this piece is that, given we have no knowledge regarding the central tendency and distribution of rodent well-being, all we can do realistically is compare the quality of deaths. Whether you view an earlier death as a positive or a negative depends on both whether you assume rodent lives are on average net positive or net negative, and whether you assume the subsequent numerous offspring are likely to experience net positive or net negative lives. We are agnostic on this, but do point out that the length of time suffering due to poisoning or starvation will be longer than the suffering due to cat predation. However, one point we raised regarding outdoor cat presence is of course that fear-based vicinity control could reduce total deaths due to both poisoning and predation (although we certainly accept that this is this is not a simple approach Bedoya-Perez et al 2019, Krijger et al. 2017).
These points aside, the reason that we frame cat predation and rodenticide use as alternatives is that if you prioritize human interests and welfare above wildlife interests (and again we are agnostic here) then you will absolutely need to come up with an alternative method of control. Commensal rodent populations have large economic and human health impacts (e.g. Meerburg et al. 2009, Stenseth et al. 2003). (As an aside, given the tremendous reproductive output, you will also need controls if you consider rodent starvation something to be averted). With respect to downstream effects, cat predation and fear generation are methods of control that may be under appreciated and which at least don’t have the far-reaching chemical contamination issues that rodenticides do.
Lit cited
Bedoya-Perez, M. A., Smith, K. L., Kevin, R. C., Luo, J. L., Crowther, M. S., & McGregor, I. S. (2019). Parameters that affect fear responses in rodents and how to use them for management. Frontiers in Ecology and Evolution, 7, 136. https://doi.org/10.3389/fevo.2019.00136
Krijger, I. M., Belmain, S. R., Singleton, G. R., Groot Koerkamp, P. W., & Meerburg, B. G. (2017). The need to implement the landscape of fear within rodent pest management strategies. Pest management science, 73(12), 2397-2402. https://doi.org/10.1002/ps.4626
Meerburg, B. G., Singleton, G. R., & Kijlstra, A. (2009). Rodent-borne diseases and their risks for public health. Critical reviews in microbiology, 35(3), 221-270. https://doi.org/10.1080/10408410902989837
Stenseth, N. C., Leirs, H., Skonhoft, A., Davis, S. A., Pech, R. P., Andreassen, H. P., … & Zhang, Z. (2003). Mice, rats, and people: the bio‐economics of agricultural rodent pests. Frontiers in Ecology and the Environment, 1(7), 367-375. https://doi.org/10.1890/1540-9295(2003)001[0367:MRAPTB]2.0.CO;2
Thanks for the detailed response. I think I disagree in a sort of principled way with particular kinds of approaches to downstream effects, in part because I think it could just turn into an endless game of trying to figure out how things could turn out poorly, as opposed to a model where we address both rodenticides and cat predation (though I recognize I am stubbornly resisting you all trying to do prioritization, which might not be a good idea given the name of your organization).
Regardless, I’m drafting a new intro section for my cost-effectiveness updates linking to your updated numbers. Thanks again for doing the analysis!
The position of this piece is that, given we have no knowledge regarding the central tendency and distribution of rodent well-being, all we can do realistically is compare the quality of deaths. Whether you view an earlier death as a positive or a negative depends on both whether you assume rodent lives are on average net positive or net negative, and whether you assume the subsequent numerous offspring are likely to experience net positive or net negative lives. We are agnostic on this, but do point out that the length of time suffering due to poisoning or starvation will be longer than the suffering due to cat predation. However, one point we raised regarding outdoor cat presence is of course that fear-based vicinity control could reduce total deaths due to both poisoning and predation (although we certainly accept that this is this is not a simple approach Bedoya-Perez et al 2019, Krijger et al. 2017).
These points aside, the reason that we frame cat predation and rodenticide use as alternatives is that if you prioritize human interests and welfare above wildlife interests (and again we are agnostic here) then you will absolutely need to come up with an alternative method of control. Commensal rodent populations have large economic and human health impacts (e.g. Meerburg et al. 2009, Stenseth et al. 2003). (As an aside, given the tremendous reproductive output, you will also need controls if you consider rodent starvation something to be averted). With respect to downstream effects, cat predation and fear generation are methods of control that may be under appreciated and which at least don’t have the far-reaching chemical contamination issues that rodenticides do.
Lit cited
Bedoya-Perez, M. A., Smith, K. L., Kevin, R. C., Luo, J. L., Crowther, M. S., & McGregor, I. S. (2019). Parameters that affect fear responses in rodents and how to use them for management. Frontiers in Ecology and Evolution, 7, 136. https://doi.org/10.3389/fevo.2019.00136
Krijger, I. M., Belmain, S. R., Singleton, G. R., Groot Koerkamp, P. W., & Meerburg, B. G. (2017). The need to implement the landscape of fear within rodent pest management strategies. Pest management science, 73(12), 2397-2402. https://doi.org/10.1002/ps.4626
Meerburg, B. G., Singleton, G. R., & Kijlstra, A. (2009). Rodent-borne diseases and their risks for public health. Critical reviews in microbiology, 35(3), 221-270. https://doi.org/10.1080/10408410902989837
Stenseth, N. C., Leirs, H., Skonhoft, A., Davis, S. A., Pech, R. P., Andreassen, H. P., … & Zhang, Z. (2003). Mice, rats, and people: the bio‐economics of agricultural rodent pests. Frontiers in Ecology and the Environment, 1(7), 367-375. https://doi.org/10.1890/1540-9295(2003)001[0367:MRAPTB]2.0.CO;2
Thanks for the detailed response. I think I disagree in a sort of principled way with particular kinds of approaches to downstream effects, in part because I think it could just turn into an endless game of trying to figure out how things could turn out poorly, as opposed to a model where we address both rodenticides and cat predation (though I recognize I am stubbornly resisting you all trying to do prioritization, which might not be a good idea given the name of your organization).
Regardless, I’m drafting a new intro section for my cost-effectiveness updates linking to your updated numbers. Thanks again for doing the analysis!