Pest Management Science (2019) 75, 900-907

Javier Fernandez-de-Simon, Michael Coeurdassier, Geoffroy Couval, Isabelle Fourel and Patrick Giraudoux (2019)
Do bromadiolone treatments to control grassland water voles (Arvicola scherman) affect small mustelid abundance?
Pest Management Science 75 (4), 900-907
Abstract:
Background
The use of pesticides can affect non-target species by causing population declines through indirect intoxication. Small mustelids (SMs; weasels, Mustela nivalis L.; stoats, Mustela erminea L.) consume water voles (WVs, Arvicola scherman S.) and can be exposed to bromadiolone, an anticoagulant rodenticide used in some countries to reduce WV damage to grasslands. Here, we investigated whether bromadiolone affected SM abundance.
Results
We monitored SM abundance using footprint tracking tunnels in spring and autumn at ten sites. Among these sites, four were treated with bromadiolone, while six were not treated. We found reduced SM abundance at these four sites from spring to autumn (treated sites, mean ± SE SM abundance change = -1.68 ± 0.42; untreated sites, 0.29 ± 0.25). Using a linear model, we observed that SM abundance decreased as a function of the quantity of bromadiolone applied during the 3 months before the autumn estimate. We found that WV abundance increased at treated sites (linear model, treated sites, mean ± SE WV abundance change = 1.4 ± 0.4; untreated sites, 0.33 ± 0.25). Thus, at treated sites, SM abundance declined despite increased food availability. By analyzing residues in vole livers and SM scats we showed that SMs may be exposed to bromadiolone at the sites where this compound was used.
Conclusion
This study is the first to document the relationship between SM abundance and bromadiolone usage for small mammal control. Declines in SM abundance were observed at treated sites, where bromadiolone residue was found in SM scats. This correlative approach suggests that bromadiolone treatment may lead to seasonal SM declines and associated WV increases.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Patrick Giraudoux

Research topic(s) for pests/diseases/weeds:
control - general
health/environmental effects of pesticides

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Arvicola scherman		France