Water Vole Research Articles

The role of the montane water vole (Arvicola scherman) as a crop pest in NW Spain: since when?

The role of the montane water vole (Arvicola scherman) as a crop pest in NW Spain: since when? / El papel de la rata topera (Arvicola scherman) como plaga agrícola en el noroeste de España: ¿desde cuándo?

Resultados del primer Sondeo de Rata de Agua, Arvicola sapidus Miller 1908, en España

The results of the first spanish southern water vole (Arvicola sapidus) survey are presented in this paper. The survey was carried out between March 19, 2011 and June 10, 2012 and 310 volunteers participated in it, of which almost half did so as companions. A total of 1,000 UTM grids of 10x10 km were selected a priori, with a uniform distribution throughout peninsular Spain. In each grid the observer chose three sampling points, with the following conditions: presence of favorable habitat, easy access and minimum distance between sampling points of 2,500 m. More than half of the grids were sampled by a single observer and 97% of the positive points were before 25 minutes of sampling. Data was obtained from 995 grids of the 1,000 initially planned. The presence of southern water vole was detected in 542 (54.5%) of grids: 218 with one positive point (40.2% of the positive ones), 174 with two (32.1%) and 150 with three (27.7%). The total number of points sampled was 2,914, of which 1,016 (34.9%) were positive.

Stratigraphy and the small mammal fauna of the Late Pleistocene sections in the south of the middle reaches of the Volga River

Two Pleistocene sections in the middle reaches of the Volga River – Spasskoe and Yagodnoe – have been described in details and analyzed, small mammal remains being recovered and identified. The fauna includes remains of open landscape species: Eolagurus luteus (Eremin and Moloskovsky, 1981), Lagurus lagurus Pallas, 1773, Lasiopodomys (Stenocranius) gregalis (Pallas, 1779) and others. Bone remains of a tundra species – collared lemming Dicrostonyx sp. were found in the Spasskoe section. No forest species are present in the sequence, nor remains of water vole Arvicola. The species richness of the faunas is rather low, which may be related to insufficient amount of material or to a specific climate. Such low species richness is typical of the periglacial faunas of the Pleistocene. The authors of recent article attribute the third Volga terrace to the Late Pleistocene refer usually to the 3rd terrace deposits in the lower reaches of the Volga where the Caspian Upper Khazarian (Hyrcanian) layers are found at the base of the sequence. The rodent molar morphology permits to date fauna to the beginning of the Late Pleistocene (to the early stages of the Valday glaciation) and to reconstruct periglacial steppes widely distributed in the Volga middle reaches at that time.

Water vole management - Could anticoagulant rodenticides stereochemistry mitigate the ecotoxicity issues associated to their use?

Cyclic water vole population explosions can be controlled in some European countries with anticoagulant rodenticides leading sometimes to wildlife poisonings due to the toxin’s tissue persistence. Here, we analyzed the pharmacokinetics of rodenticide residues in voles and we explored potential ways of improving the mass application of these agents based on the concept of stereoisomers.We demonstrated the dramatic persistence of bromadiolone in vole tissues with a hepatic half-life of about 10–30 days, while the tissue persistence of chlorophacinone is rather short with a hepatic half-life of about one day. The dramatic persistence of bromadiolone is due to the trans-isomer group (the major compound in bromadiolone), while the cis-isomer group has a short half-life. Because of resistance to chlorophacinone, the cis-bromadiolone isomers may constitute an excellent compromise between efficacy and ecotoxicological risk to control voles. A mathematical model is proposed to favor the development of baits mixed with cis-isomer groups.

At the southern fringe: extant and fossil water voles of the genus Arvicola (Rodentia, Cricetidae, Arvicolinae) from Israel, with the description of a new species

ABSTRACT The (palaeo)biogeography of water voles is a puzzle that is not solved in detail yet. Extant species of the genus Arvicola cover a vast geographic area of the Palearctic. In this study, we collected morphometric data of extant and fossil Arvicola from Israel at the southern fringe of the water vole distribution area. The dental evolution of water voles is characterised by certain clear trends in the first lower molar (m1) related to crown height, tooth length, the proportion of the anteroconid-complex, and enamel differentiation. Trans-regional correlation of the latter trend shows that it did not develop completely synchronously in all the geographic areas of water voles’ distribution, i.e., not at the same evolutionary rate. Based on the size and geographic distribution, we tentatively consider the Israeli material to belong to an A. persicus group, which facilitates the possibility of future taxonomic subdivision. Among the Israeli material, Late Pleistocene remains from Nahal Mahanayeem Outlet (NMO) show a very particular morphology of the first lower molar compared to samples from other localities in Israel and western Asia, which – in our opinion – justifies the establishment of a new species Arvicola nahalensis n. sp.

Changes in the geographical distribution of Microtus (Iberomys) cabrerae (Thomas, 1906) from the Late Pleistocene to the Holocene

Cabrera’s vole, Microtus (Iberomys) cabrerae, is a currently endemic species restricted to Spain and Portugal. Its present day distribution is fragmentary, but in the past it was broadly distributed across the Iberian Peninsula, with the exception of the northern part of the Peninsula. Various hypotheses have been expounded to explain the retraction of the species since the beginning of the Holocene: 1) the climate changes produced in the Bronze Age; 2) the human impact on the restricted habitat of the species; and 3) its direct competition with other species with similar environmental requirements, such as the southern water vole (Arvicola sapidus), an Iberian endemism. In this paper, we discuss these hypotheses regarding the distribution of the species fossil record in the Late Pleistocene and beginning of the Holocene, as well as its current distribution. The most plausible hypothesis for its retraction is human impact, which has destroyed the habitat of the species with the development of agriculture and road infrastructures and the increasing human population

Applying IUCN reintroduction guidelines: An effective medium for raising public support prior to conducting a reintroduction project

IUCN guidelines state that public support for conservation projects should be garnered prior to any ‘on the ground’ activities taking place, as public knowledge and support, both passive and / or active, can influence greatly the success of a species reintroduction. This study investigated the effectiveness of generating public support within a zoo setting for a conservation species reintroduction project. Questionnaires were completed by public visiting the zoo allowing data collection, pre and post the display of the species, that provided an opportunity to report on the impact a species presence has on generating levels of support. Generally, passive support was very high for the project, but increased after the red-billed chough were viewable to the public. However, levels of donations reduced once the species was visible to the public, with people appearing to favour mammalian species over a bird species. However, red-billed chough raised more ‘virtual’ funding than water vole, which was not on public display. Innate favouritism or likeability for a species appeared to play a major role in decision making by the public, indicating that where conservation conflicts may arise they would lend support to ‘likeable’ over ‘dull’ species regardless of conservation priorities. This indicates greater education would be needed in such cases to reinforce the wider conservation positives from proposed projects. Whilst not all human dimensions were measured here, the study showed that education and having an animal on display can positively raise public passive support and potential active support for a conservation project.

Близькі види гризунів надродини Muroidei у фауні України: таксономія, біогеографія, діагности-ка, екоморфологія

The results of the revision of the species composition and related knowledge of taxonomy, biogeography, diagnostics, variability and ecomorphology of polytypic groups of murine rodents, superfamily Muroidei, are presented. These are 5 former "large" species: "wood mice", "common mice", water voles, "shrub voles" and "common voles". Each of these groups is represented in the fauna of Ukraine and neighboring countries by 2–3 species. The two most difficult for revision and for background monitoring of fauna are "forest mice" and "common voles", each of which is represented in the fauna of the region by three morphologically very similar species of different kinship, among which one (the most genetically distant) is widely sympatric to the other two species that are allospecies. Among "forest mice", such species are Sylvaemus uralensis (= microps) against the pair S. sylvaticus + S. witherbyi (= S. falzfeini), and among the "common voles" it is Microtus levis (= rossiaemeridionalis) against the pair M. arvalis + M. obscurus. The other three pairs of species are generally more diverged (at least in terms of habitats and ecology, and in some cases morphology) and clearly less sympatric species. In the group of "common" mice, Mus "musculus" (s.l.), there is a pair of synanthropic and exanthropic forms — M. musculus and M. spicilegus (= M. sergii), which usually do not interact in nature, and therefore poorly diverged in morphology. In the group of "water voles" there is an allopatric pair, represented by the Carpathian-Roztochchian (essentially mountainous, associated with meadows) as well as plain hydrophilic forms, Arvicola scherman and A. amphibius (= A. terrestris). In the group of "shrub voles" there is a sympatric pair of species, one of them has limited distribution in the Carpathians (Terricola tatricus), but the other (T. subterraneus), being sympatric to the first in the Carpathians, also forms numbered populations in lowland forests, as in the forest zone as in the bairak steppe zone. Morphological differentiation between them is generally high, but the Eastern Carpathian form of Terricola tatricus is the smallest in a row of mountain forms of Terricola (multiplex, tatricus, zykovi), which was the reason for its long-term non-recognition in the fauna of Ukraine. For all species, descriptions are presented, including 5 standard parts for this series of publications: general remarks, taxonomy (including nomenclature), distribution (including biotopes), diagnostics (including variability), ecomorphology.Key words: small mammals, habitats, dominance, abundance of species.

Мишоподібні гризуни та землерийки в Харківській області (Україна):видовий склад, поширення, стан популяцій

Since 1957, zoologists of the Kharkiv Sanitary and Epidemiological Station have been conducting annual monitoring of small mammals in Kharkiv Oblast. To assess the current state of populations of mouse-like rodents and shrews, we analysed a dataset for the period from 2000 to 2018. The small mammal fauna was studied at 117 sites in 27 districts (raions) of Kharkiv Oblast. Various types of oak forests, dry and floodplain meadows, riparian vegetation, steppe areas, forest stripes, gardens, fields, and haystacks were examined. Four species of insectivores and 16 species of mouse-like rodents were identified. The dominant and widespread species in the region are Sylvaemus uralensis, Apodemus agrarius, Sorex araneus, Microtus levis, Myodes glareolus, and Sylvaemus tauricus. Some species are less common and in some areas of the region have not yet been identified, including Sorex minutus, Sylvaemus sylvaticus, Crocidura suaveolens, Micromys minutus, Cricetulus migratorius, and Microtus oeconomus. The least common species with single records include Neomys fodiens, Mus spicilegus, Lagurus lagurus, Terricola subterraneus, Dryomys nitedula, and Arvicola amphibius. Indigenous species of the region include seven species, another seven species are those that increased their number and range, three species have recently appeared in the region due to dispersal from adjacent territories, while, on the contrary, the abundance and range of three species have declines. Microtus oeconomus is characterised by a current southward range expansion. Myodes glareolus, which was mentioned in the last century north of our region, is now widely distributed throughout the region and further south. Lagurus lagurus is an invasive species with periodic population outbreaks in the region and currently is rarely recorded.

The swarming life of pastures: living with vole outbreaks in the French Jura uplands

This paper addresses the joint becoming of landscapes, agricultural tasks and prairie rodents in the French Jura uplands, where the development of hay monoculture triggered outbreaks of water voles that reduce pastures to dust. I explore links between processual landscape anthropology and contemporary scholarship on more‐than‐human entanglements in order to follow how ecological disruptions called for the development of new arts of noticing towards multispecies life. I first describe the relationships between Jura farmers, voles, fields and agricultural modernisation programmes, and suggest that vole outbreaks bring these together around shared tasks. I then consider how disputes over how to control voles led to changes in farmers’ ways of caring for their cows and tending the fields. I argue that these underlined changes in their ways of understanding and responding to the rhythms of the landscape’s more‐than‐human activities. Finally, I draw on the example of conflicts between farmers over whether cows or pastures should be more central to their work. I make the case that to be attentive to fields as a landscape in the Jura is ultimately to define the (in)appropriateness of certain actions and tasks. It becomes constitutive of what ‘good farming’ should be, and precipitates new identities.

ECTOPARASITES OF A STEPPE LEMMING LAGURUS LAGURUS PALLAS, 1773 IN THE SOUTH TRANS-URAL REGION (KURGAN OBLAST) IN CONNECTION WITH THE NATURAL FOCI OF TULAREMIA

Steppe lemming of the South Trans-Ural region is a rare species of open spaces. To the north, its distribution is limited to the subzone of herb-bunchgrass steppes and the southern strip of the forest-steppe subzone. The presented work summarizes the material, which gives the full species composition of the parasitic arthropods of this rodent, and gives quantitative characteristics of ectoparasites. In total 155 individuals and one nest of steppe lemming were examined for ectoparasites. There are 808 parasitic arthropods of 20 species, including 14 species of gamasid mites, 2 species of ixodid ticks and 4 species (subspecies) of fleas. According to the number of individuals of ectoparasites feeding on the steppe lemming, the dominance of gamasid mites is strongly pronounced, both prevailing multi-host species and specific, typical for other rodents (gray and red-backed voles, northern mole vole, Eurasian water vole, northern birch mouse). The contribution of ixodid ticks and fleas to the parasitofauna of the steppe lemming is small. Steppe lemming can be involved in circulation of a causative agent of tularemia in the South Trans-Ural region, but as an additional carrier in maintenance of a foci in biotopes, where it contacts the habitats of the Eurasian water vole.

Complete mitochondrial genome of the water vole, Microtus richardsoni (Cricetidae, Rodentia)

Water voles (Microtus richardsoni) are sensitive species distributed in the mountains of Canada (Alberta, British Columbia), and the United States of America (Idaho, Montana, Oregon, Utah, Washington, and Wyoming). We assembled the complete circular M. richardsoni mitogenome, which is 16,285 bp in length and encodes 13 protein-coding genes, 22 tRNA genes, and two rRNA genes. We estimated the phylogenetic tree of M. richardsoni and 24 related arvicoline species with two outgroup species: Phodopus roborovskii and Cricetus cricetus.

Vole disturbances and plant community diversity in a productive hay meadow

It is recognized that disturbances by fossorial small mammals are important factors determining plant community diversity, especially in grasslands. However, although information about the effects of disturbances by fossorial small mammals on species richness are starting to accumulate, we know little about the impact of these disturbances on the functional and phylogenetic facets of plant community diversity in grasslands.In a study site located in the French Jura Mountains, we compared taxonomic, functional and phylogenetic diversity of plant communities in areas highly disturbed by montane water vole (Arvicola terrestris) with areas lowly disturbed by this small mammal. In accordance with previous studies, we found that species richness was higher in highly disturbed communities. Indeed, competitive species unable to withstand disturbances were less abundant in disturbed communities, allowing species less adapted to competition for light to survive. Because these species have different trait values in comparison to strong competitors, functional richness was also higher in highly disturbed communities. Results were similar for phylogenetic richness, maybe due to the fact that the used metric was not independent from species richness. Although species composition differed between highly and lowly disturbed communities, functional composition was very similar. Thereby, the studied disturbances were probably not strong enough to affect plant community functioning. Rao functional diversity and functional evenness were not different between both community types. Interestingly, phylogenetic evenness was lower in highly disturbed areas, supporting the idea that disturbances might select for disturbance tolerance traits that are phylogenetically conserved.Though correlational, our results suggest that water vole disturbances may modify multiple facets of plant community diversity, while ecosystem functioning is maintained across disturbance levels. Further research is needed to understand causal mechanisms in this system and the ecological repercussions of small mammal disturbances more broadly.

Spatio-temporal trends in richness and persistence of bacterial communities in decline-phase water vole populations

Understanding the driving forces that control vole population dynamics requires identifying bacterial parasites hosted by the voles and describing their dynamics at the community level. To this end, we used high-throughput DNA sequencing to identify bacterial parasites in cyclic populations of montane water voles that exhibited a population outbreak and decline in 2014–2018. An unexpectedly large number of 155 Operational Taxonomic Units (OTUs) representing at least 13 genera in 11 families was detected. Individual bacterial richness was higher during declines, and vole body condition was lower. Richness as estimated by Chao2 at the local population scale did not exhibit clear seasonal or cycle phase-related patterns, but at the vole meta-population scale, exhibited seasonal and phase-related patterns. Moreover, bacterial OTUs that were detected in the low density phase were geographically widespread and detected earlier in the outbreak; some were associated with each other. Our results demonstrate the complexity of bacterial community patterns with regard to host density variations, and indicate that investigations about how parasites interact with host populations must be conducted at several temporal and spatial scales: multiple times per year over multiple years, and at both local and long-distance dispersal scales for the host(s) under consideration.

Genetic structure, ecological versatility, and skull shape differentiation inArvicolawater voles (Rodentia, Cricetidae)

Water voles from the genus Arvicola display an amazing ecological versatility, with aquatic and fossorial populations. The Southern water vole (Arvicola sapidus) is largely accepted as a valid species, as well as the newly described Arvicola persicus. In contrast, the taxonomic status and evolutionary relationships within Arvicola amphibius sensu lato had caused a long-standing debate. The phylogenetic relationships among Arvicola were reconstructed using the mitochondrial cytochrome b gene. Four lineages within A. amphibius s.l. were identified with good support: Western European, Eurasiatic, Italian, and Turkish lineages. Fossorial and aquatic forms were found together in all well-sampled lineages, evidencing that ecotypes do not correspond to distinct species. However, the Western European lineage mostly includes fossorial forms whereas the Eurasiatic lineage tends to include mostly aquatic forms. A morphometric analysis of skull shape evidenced a convergence of aquatic forms of the Eurasiatic lineage toward the typically aquatic shape of A. sapidus. The fossorial form of the Western European lineage, in contrast, displayed morphological adaptation to tooth-digging behavior, with expanded zygomatic arches and proodont incisors. Fossorial Eurasiatic forms displayed intermediate morphologies. This suggests a plastic component of skull shape variation, combined with a genetic component selected by the dominant ecology in each lineage. Integrating genetic distances and other biological data suggest that the Italian lineage may correspond to an incipient species (Arvicola italicus). The three other lineages most probably correspond to phylogeographic variations of a single species (A. amphibius), encompassing the former A. amphibius, Arvicola terrestris, Arvicola scherman, and Arvicola monticola.

Rats as potential reservoirs for neglected zoonotic Bartonella species in Flanders, Belgium

BackgroundBartonella spp. are vector-borne pathogens transmitted to humans via blood-sucking arthropods. Rodents such as the black rat (Rattus rattus) and Norway rat (R. norvegicus) are thought to be the main reservoirs. An infection with rodent-associated Bartonella spp. may cause severe symptoms in humans such as endocarditis and neuroretinitis. The current knowledge of Bartonella prevalence in rats from western Europe is scarce.MethodsRats and a few other rodent by-catches were trapped in the context of a rodenticide resistance study at different sites in Flanders, Belgium. During dissection, biometric data were collected, and spleen tissues were taken. DNA was extracted from spleen samples and tested for Bartonella spp. by conventional generic polymerase chain reaction (PCR). To determine the Bartonella species, a selected number of amplicons were sequenced and compared with GenBank entries.ResultsIn total, 1123 rodents were trapped. The predominate species was R. norvegicus (99.64%). Other rodents trapped included: two water voles (Arvicola amphibius, 0.18%); one colour rat (R. norvegicus forma domestica, 0.09%); and one muskrat (Ondatra zibethicus, 0.09%). PCR analysis of 1097 rodents resulted in 410 (37.37%, 95% CI: 34.50–40.31%) Bartonella spp. DNA-positive samples. Bartonella tribocorum (94.68%, 95% CI: 88.02–98.25%) was the most frequently detected Bartonella species, followed by B. grahamii (3.19%, 95% CI: 0.66–9.04%) and B. doshiae (1.06%, 95% CI: 0.03–5.79%). An uncultured Bartonella species occurred in one water vole (1.06%, 95% CI: 0.03–5.79%). There was a significantly higher Bartonella prevalence in older rats compared to juveniles and a significant difference in Bartonella prevalence concerning the localisation of trapping sites. In contrast, there was no statistically significant difference in Bartonella prevalence regarding sex, degree of urbanisation and season.ConclusionsBased on the high prevalence found, we conclude that the Norway rat seems to be a key reservoir host for zoonotic B. tribocorum in Belgium.

Farmers’ perceptions and knowledge of natural enemies as providers of biological control in cider apple orchards

While the importance of biological control for crop production is widely acknowledged, research on how farmers perceive on-farm natural enemies remains scarce. This paper examines cider-apple farmers' perceptions and knowledge of the concept of biological control and the specific organisms underpinning its provision (i.e. natural enemies) in the cider-apple orchards of Asturias (N Spain). Although these orchards host a high diversity of natural enemies, certain pests continue to be a problem, e.g. the codling moth and the fossorial water vole. By conducting 90 face-to-face surveys, we found that farmers “under-estimated” the importance of biological control and the role played by natural enemies in suppressing pests from cider-apple orchards. Furthermore, farmers were particularly unaware of the indirect benefits of biological control, such as the increased quality and yield of product. Farmers also perceived that different taxa of natural enemies contribute to biological control to differing extents, for example, birds, such as buzzard, robin and tit, were perceived as the most important natural enemies, while arachnids and insects (excluding ladybug) were perceived as less important. This perceived difference in the biological control contribution of vertebrates and invertebrates could be influenced by farmers' local knowledge, acquired on-farm through daily experiences, as well as from external sources. In addition, we found that farmers did recognize many interactions between natural enemies and pests, although there were serious misconceptions and knowledge gaps. Finally, we revealed that education level, being a full-or part time farmer rather than a ‘hobby’ farmer, time spent working in agriculture, and orchard size are all factors that positively influence farmer's perception of natural enemies. Our results provide insights for a future management of cider-apple orchards which promotes biological control through: (1) creating initiatives to develop farmers' knowledge regarding biological control and natural enemies, (2) fostering traditional farming systems that contribute to preserving local ecological knowledge of biological control, and (3) establishing networks of farmers so they can learn from each other and share local knowledge.

Genetic structure of regional water vole populations and footprints of reintroductions: a case study from southeast England

An important consideration when implementing species management is preserving genetic variation, which is fundamental to the long-term persistence of populations and adaptive potential of the species. The European water vole Arvicola amphibius is of high conservation importance in the United Kingdom due to its documented decline in both distribution and abundance. Conservation strategies for this species include protecting source populations, increasing habitat availability and connectivity, non-native predator control and reintroduction. We used mtDNA control region sequences and eight microsatellite markers from samples collected from 12 localities in southeast England, to determine how genetic variation is structured amongst regional water vole populations and to what extent population structure has been influenced by reintroductions. We found high haplotype diversity (h) across native populations in the southeast region and evidence that divergent lineages had been introduced to the region. We detected significant structure between watersheds with mtDNA from native populations and evidence of finer scale structure between populations within watersheds with both mtDNA and microsatellites. We suggest that management strategies should aim to conserve genetic diversity at a population level and that watersheds are a practicable unit for prioritising management within regions. We propose that introductions to restore or augment water voles within watersheds should consider the genetic composition of regional populations and highlight that genetic data has an important role in guiding future conservation options that secure adaptive potential in the face of future environmental change.

Fishing for mammals: Landscape‐level monitoring of terrestrial and semi‐aquatic communities using eDNA from riverine systems

Abstract Environmental DNA (eDNA) metabarcoding has revolutionized biomonitoring in both marine and freshwater ecosystems. However, for semi‐aquatic and terrestrial animals, the application of this technique remains relatively untested. We first assess the efficiency of eDNA metabarcoding in detecting semi‐aquatic and terrestrial mammals in natural lotic ecosystems in the UK by comparing sequence data recovered from water and sediment samples to the mammalian communities expected from historical data. Secondly, using occupancy modelling we compared the detection efficiency of eDNA metabarcoding to multiple conventional non‐invasive survey methods (latrine surveys and camera trapping). eDNA metabarcoding detected a large proportion of the expected mammalian community within each area. Common species in the areas were detected at the majority of sites. Several key species of conservation concern in the UK were detected by eDNA sampling in areas where authenticated records do not currently exist, but potential false positives were also identified. Water‐based eDNA metabarcoding provided comparable results to conventional survey methods in per unit of survey effort for three species (water vole, field vole and red deer) using occupancy models. The comparison between survey ‘effort’ to reach a detection probability of ≥.95 revealed that 3–6 water replicates would be equivalent to 3–5 latrine surveys and 5–30 weeks of single camera deployment, depending on the species. Synthesis and applications. eDNA metabarcoding can be used to generate an initial ‘distribution map’ of mammalian diversity at the landscape level. If conducted during times of peak abundance, carefully chosen sampling points along multiple river courses provide a reliable snapshot of the species that are present in a catchment area. In order to fully capture solitary, rare and invasive species, we would currently recommend the use of eDNA metabarcoding alongside other non‐invasive surveying methods (i.e. camera traps) to maximize monitoring efforts.

Trophic transfer of pesticides: The fine line between predator–prey regulation and pesticide–pest regulation

Abstract Understanding pesticide impacts on populations of target/non‐target species and communities is a challenge to applied ecology. When predators that otherwise regulate pest densities ingest prey contaminated with pesticides, this can suppress predator populations by secondary poisoning. It is, however, unknown how species relationships and protocols of treatments (e.g. anticoagulant rodenticide [AR]) interact to affect pest regulation. To tackle this issue, we modelled a heuristic non‐spatialized system including montane water voles, specialist vole predators (stoats, weasels) and a generalist predator (red fox) which consumes voles, mustelids and other prey. By carrying out a broad‐range sensitivity analysis on poorly known toxicological parameters, we explored the impact of five farmer functional responses (defined by both AR quantity and threshold vole density above which AR spreading is prohibited) on predator–prey interactions, AR transfer across the trophic chain and population effects. Spreading AR to maintain low vole densities suppressed mustelid and fox populations, leading to vole population dynamics being entirely regulated by AR use. Such vole‐suppression treatment regimes inhibited predation ecosystem services and promoted pesticide dependence. Keeping vole density below acceptable bounds by spreading AR while maintaining sufficient voles as prey resources led to less AR being applied and extended periods without AR in the environment, benefiting predators while avoiding episodes with high vole density. This may meet farm production interests while minimizing the impact on mustelid and fox populations and associated ecosystem processes. These alternating phases of mustelids and farmer regulation highlight the consequence of intraguild relationship where mustelids may rescue foxes from poisoning. Both global and wide‐range sensitivity analysis illustrate the tightrope between predator–prey regulation and pesticide–pest regulation. Synthesis and applications. Different pesticide protocols lead to a rich variety of predator–prey dynamics in agro‐ecosystems. Our model reveals the need to maintain refuges with sufficient non‐poisoned voles for sustaining specialist mustelids, to conserve the predator community given the potential of secondary poisoning with rodenticides. We suggest that long periods without pesticide treatment are essential to maintain predator populations, and that practices of pesticides use that attempt to permanently suppress a pest over a large scale are counterproductive.