Genetic non-invasive sampling (gNIS) as a cost-effective tool for monitoring elusive small mammals

European Journal of Wildlife Research, Journal Year: 2018, Volume and Issue: 64(4)

Published: July 17, 2018

Genetic non-invasive sampling (gNIS) may provide valuable information for population monitoring, as it allows inferences of density and key behavioural traits such dispersal, kinship reproduction. Despite its enormous potential, gNIS has rarely been applied to small mammals, which live-trapping is still the most commonly used method. Here we evaluated applicability cost-effectiveness compared with live-trapping, monitor a metapopulation an Iberian endemic elusive rodent: Cabrera vole (Microtus cabrerae). We genetic diversity, dispersal movements inferred using both methods. For that, optimised microsatellite markers individual identification M. cabrerae, tissue (n = 31) faecal samples 323) collected from in south-western Iberia. An initial set 20 loci was samples, 11 were selected amplify samples. Overall, revealed higher number identified individuals (65) than (31), estimated diversity similar data tissues gNIS. Kinship analysis showed relationships events when including gNIS, indicated absence sex-biased dispersal. The total cost (fieldwork analysis) each genotype obtained through three times greater Our strongly supports high potential monitoring populations and/or threatened mammals. also illustrate how this tool can be logistically feasible conservation.

Language: Английский

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Noninvasive Genetic Assessment Is an Effective Wildlife Research Tool When Compared with Other Approaches

Genes, Journal Year: 2021, Volume and Issue: 12(11), P. 1672 - 1672

Published: Oct. 23, 2021

Wildlife research has been indispensable for increasing our insight into ecosystem functioning as well designing effective conservation measures under the currently high rates of biodiversity loss. Genetic and genomic analyses might be able to yield same information on, e.g., population size, health, or diet composition other wildlife methods, even provide additional data that would not possible obtain by alternative means. Moreover, if DNA is collected non-invasively, this technique only minimal no impact on animal welfare. Nevertheless, implementation rate noninvasive genetic assessment in studies rather low. This caused perceived inefficiency material obtained non-invasively comparison with from blood tissues, poorer performance approaches used research. Therefore, aim review was evaluate methods across different types studies. Through a search three scientific databases, 113 relevant were identified, published between years 1997 2020. Overall, most (94%) reported equivalent superior when compared either invasive sampling another method. It also cheaper more time-efficient than techniques. In conclusion, highly approach, whose efficacy are likely improve further future development optimized protocols.

Language: Английский

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Testing the effectiveness of genetic monitoring using genetic non‐invasive sampling

Ecology and Evolution, Journal Year: 2021, Volume and Issue: 12(1)

Published: Dec. 27, 2021

Abstract Effective conservation requires accurate data on population genetic diversity, inbreeding, and structure. Increasingly, scientists are adopting non‐invasive sampling (gNIS) as a cost‐effective population‐wide monitoring approach. gNIS has, however, known limitations which may impact the accuracy of downstream analyses. Here, using high‐quality single nucleotide polymorphism (SNP) from blood/tissue free‐ranging koala ( n = 430), we investigated how reduced SNP panel size call rate typical samples (derived experimental field trials) impacts measures, also effect intensity these measures. We found that at small sample sizes (14% population) can provide diversity but slightly underestimated inbreeding coefficients. Accurate measures internal relatedness required least 33% to be sampled. geographic spatial autocorrelation analysis between 28% 51% show low powerful tool aid decision‐making recommendations for researchers looking apply techniques systems.

Language: Английский

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Monitoring of free-range rabbits using aerial thermal imaging

Smart Agricultural Technology, Journal Year: 2021, Volume and Issue: 1, P. 100002 - 100002

Published: Sept. 16, 2021

Unmanned Aerial Vehicles (UAV) imagery is a mature technology, which has found use in number of applications agriculture and environmental sciences. However, its application for monitoring classification livestock wild animals not yet been developed. This study presents robust methodology to count free-range rabbits monitor their population. The aims this were 1) test the capacity counting small nocturnal such as field, 2) assess rabbit's density at different sites periods year 3) record temporal pattern rabbits' activity during night hours, with overall aim provide reliable accurate tool management studies. For purpose, UAV equipped thermal camera was used perform flights on island Lemnos, scanning selected collecting aerial nadir data ground. derived images analysed using deep learning techniques towards individual each image results compared manual conducted by researcher. revealed that approach automated rabbit recognition achieved comparable physical counting, final model yielding an F1-score 0.87. there differences between seasons methods' accuracy. method could be helpful assessing populations other animals.

Language: Английский

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Landscape Characteristics Affecting Small Mammal Occurrence in Heterogeneous Olive Grove Agro-Ecosystems

Conservation, Journal Year: 2022, Volume and Issue: 2(1), P. 51 - 67

Published: Jan. 10, 2022

Understanding how small mammals (SM) are associated with environmental characteristics in olive groves is important to identify potential threats agriculture and assess the overall conservation value functioning of agro-ecosystems. Here, we provide first insights on this topic applied traditional northeast (NE) Portugal by assessing landscape attributes that determine SM occurrence, focusing one species concern (Microtus cabrerae Thomas 1906) often perceived as a pest olives lusitanicus Gerbe 1879). Based genetic non-invasive sampling 51 surrounding habitats, identified seven rodent insectivore. Occupancy modelling indicated were generally less detected within than habitats. The vulnerable M. reached mean occupancy (95% CI) 0.77 (0.61–0.87), while stood at 0.37 (0.24–0.52). was more likely occur land mosaics high density agricultural field edges, pastureland patches. Overall, our study suggests complex structure spatial heterogeneity traditionally managed grove agro-ecosystems may favor occurrence species-rich communities, possibly including well-established populations importance, keeping relatively low rates.

Language: Английский

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Comparison of grizzly bear hair‐snag and scat sampling along roads to inform wildlife population monitoring

Wildlife Biology, Journal Year: 2020, Volume and Issue: 2020(3), P. 1 - 12

Published: Sept. 16, 2020

Wildlife managers conduct population inventories to monitor species, particularly those at‐risk. Although costly and time consuming, grid‐based DNA hair‐snag sampling has been the standard protocol for grizzly bear in North America, while opportunistic fecal is more commonly used Europe. Our aim determine if low‐cost, low‐effort scat along roads can replace current standard. We compare two genetic non‐invasive techniques using concurrent within same grid system spatially explicit capture–recapture. found that given our methodology present status of genotyping bears, cannot hair estimate size low‐density areas. Hair identified majority individual with a higher success rate individuals from samples (100%) compared (14%). Using supplement data did not change estimates, but it improve precision. Scat had identifying species (98%) (80%). detected bears cells where showed non‐detection, almost twice number indicating presence. Based on methods projected expenses future implementation, we estimated an approximate 30% cost reduction relative hair. research explores application approaches populations. recommend wildlife continue use as primary method inventories, employing supplemental increase may better indicate presence through greater numbers spatial distribution detections, systematic across entire area interest. findings speak management other regions, contribute ongoing advances monitoring

Language: Английский

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Feeding preferences in dry season of the Italian hare (Lepus corsicanus) in two sites of Corsica

European Journal of Wildlife Research, Journal Year: 2019, Volume and Issue: 65(3)

Published: May 3, 2019

Language: Английский

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Competition between sympatric hare species in the Alps is boostered by climate change and hybridisation

European Journal of Wildlife Research, Journal Year: 2024, Volume and Issue: 70(4)

Published: July 25, 2024

Abstract Climatic variation along the elevation gradient promotes natural parapatric occurrence of European hare ( Lepus europaeus ) and Alpine mountain timidus varronis in Alps. Recent data indicate a displacement hares caused by competition with hare. Competitive exclusion might take place at fine spatial scale hybrids may sharpen competition. Genetic non-invasive sampling (gNIS) demonstrates to be effective retrieve information from wild animals. However, based on accuracy differing genetic analysis methods, selection method decisively influence results. To examine habitat preferences hares, their particular interest results, we performed gNIS Grisons (Switzerland) for four years compared associations genotyped samples. We recorded 137 individuals (i.e., 35 hybrids, 49 53 hares). Combined nuclear mitochondrial DNA including individual identification revealed most accurate indirect study hares. had narrow breadth used little diversity. Hybrids showed great similarities increase favour since they show similar patterns use Ongoing climate change potentiate niche overlap between species, increasing risk decline due hybridisation displacement.

Language: Английский

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Patch spatial attributes and time to disturbance affect the emergence of source local populations within ephemeral habitats

Ecological Modelling, Journal Year: 2024, Volume and Issue: 496, P. 110839 - 110839

Published: Aug. 22, 2024

Understanding the demography of local populations within ephemeral habitat patches is crucial for effective (site-based) conservation management in spatially and temporally heterogeneous environments.Evidence suggests that species persisting networks often exhibit source-sink dynamics, where certain act as temporary sources at some time between initial colonization patch disappearance due to disturbance.Here we present an individual-based demographic model inspired by Cabrera voles (Microtus cabrerae) dynamic agricultural mosaics test hypothesis emergence a source population largely driven combined effects spatial attributes (size, internal quality connectivity other hypothetical patches) disturbance (i.e. lifespan).We focused on two key emergent metrics quantifying status based their self-sustainability potential contribution patches.We used sensitivity analyses estimate strength linear associations these attributes, quantify main interaction across different lifespans since colonization.Our revealed considerable temporal variation may emerge populations' differences size, quality, connectivity, lifespan.According predictions, correlated positively with patches, though relationships was mostly relevant only after about three vole generation times (ca.one year) colonization, combination positive size connectivity.Accordingly, results also supported prediction conditional longevity patch, short (less than times) greatly limiting patches.While empirical testing needed confirm findings, our study strengthens view efforts focusing reducing or mitigating (e.g.severe droughts, human farming activities) large well-connected high-quality will likely promote occurrence populations, which should be long-term persistence over larger scales.

Language: Английский

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From species detection to population size indexing: the use of sign surveys for monitoring a rare and otherwise elusive small mammal

European Journal of Wildlife Research, Journal Year: 2022, Volume and Issue: 69(1)

Published: Dec. 23, 2022

Abstract Monitoring the occupancy and abundance of wildlife populations is key to evaluate their conservation status trends. However, estimating these parameters often involves time resource-intensive techniques, which are logistically challenging or even unfeasible for rare elusive species that occur patchily in small numbers. Hence, surveys based on field identification signs (e.g. faeces, footprints) have long been considered a cost-effective alternative monitoring, provided they produce reliable detectability meaningful indices population abundance. We tested use sign monitoring otherwise mammals, focusing Cabrera vole ( Microtus cabrerae ) Portugal. asked how sampling intensity affects true positive detection species, whether related size. surveyed voles’ latrines 20 habitat patches known be occupied, estimated ‘true’ size at each patch using DNA-based capture-recapture techniques. found searching rate ca. 3 min/250m 2 adaptive guided transects was sufficient provide probabilities > 0.85. Sign-based were best moderately correlated with estimates size, so only rates 12 . Our study suggests should option estimate voles, possibly other but cautions exercised when this approach infer In case practical constraints more accurate methods, considerable needed reliably index from surveys.

Language: Английский

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