Camera traps and activity signs to estimate wild boar density and derive abundance indices

Massei, Giovanna; Coats, Julia; Lambert, Mark; Pietravalle, Stéphane; Gill, Robin; Cowan, David P.

doi:10.1002/ps.4763

Cited by 39 publications

(45 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In particular, the model predicted growth over the first few years which appears inflated as the initial high density population spreads out; in reality populations tend to have lower density at the range edge, resulting in a more stable rate of spread and assuming no resistance from hunting pressure. Recent methods for estimating density of feral wild boar from camera trapping and/or through distance sampling could be used [22, 23] together with engagement of the local land owners to gather this information.…”

Section: Discussionmentioning

confidence: 99%

The risk of foot-and-mouth disease becoming endemic in a wildlife host is driven by spatial extent rather than density

et al. 2019

Self Cite

View full text Add to dashboard Cite

In the past 20 years, free living populations of feral wild boar have re-established in several locations across the UK. One of the largest populations is in the Forest of Dean where numbers have been steadily increasing since monitoring began in 2008, with estimates from 2016 reporting a population of more than 1500. Feral wild boar have significant ecological and environmental impacts and may present a serious epidemiological risk to neighbouring livestock as they are a vector for a number of important livestock diseases. This includes foot-and-mouth disease (FMD) which is currently absent from the UK. We developed an individual-based spatially explicit modelling approach to simulate feral wild boar populations in the Forest of Dean (England, UK) and use it to explore whether current or future populations might be sufficient to produce long-lived outbreaks of FMD in this potential wildlife reservoir. Our findings suggest that if you exclude the spread from feral wild boar to other susceptible species, the current population of boar is insufficient to maintain FMD, with 95% of unmanaged simulations indicating disease burn-out within a year (not involving boar management specifically for disease). However, if boar are allowed to spread beyond their current range into the adjacent landscape, they might maintain a self-sustaining reservoir of infection for the disease.

show abstract

Section: Discussionmentioning

confidence: 99%

The risk of foot-and-mouth disease becoming endemic in a wildlife host is driven by spatial extent rather than density

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…Study limitations are not surprising, given this is the first wild pig toxicant field study to be conducted in North America. During future warfarin bait field trials, researchers should strive to estimate the number and size of sounders prior to study initiation, possibly using methods similar to those described by [ 78 ], and an effort should be made to distribute GPS collars and VHF ear tags amongst them with proportional homogeneity. This could potentially improve efficacy estimates and the capacity to analyze results statistically.…”

Section: Discussionmentioning

confidence: 99%

Field evaluation of low-dose warfarin baits to control wild pigs (Sus scrofa) in North Texas

Poché

Franckowiak

et al. 2018

PLoS ONE

View full text Add to dashboard Cite

Wild pigs (Sus scrofa) are a highly detrimental invasive species that occupy a rapidly expanding range within the United States. In Australia, field trials evaluating baits containing 0.09% warfarin resulted in wild pig population reduction >95%. The objective of this study was to conduct an EPA-approved field trial to evaluate the use of bait containing low-dose warfarin (0.01% and 0.005%) in reducing wild pig numbers in Texas. An 8-week field test was conducted in the panhandle ~100 km southeast of Amarillo. Two ~8 km2 treatment plots were selected and each presented with either 0.01% or 0.005% warfarin baits. One control plot (~8 km2) was presented placebo. The baits were delivered using 30 species-specific feeders per plot (n = 90) that kept wildlife from accessing the toxicant. Pig movements and feed consumption were monitored during pre-treatment, treatment, and post-treatment periods. All pigs with VHF transmitters within the 0.005% warfarin-treated plot (n = 14) succumbed to the warfarin (100% mortality). Overall, 35 wild pigs were found dead from warfarin toxicosis, within both treatment plots. Total feed consumption by wild pigs was reduced by ~97.8% and ~96.2% for the 0.005% and 0.01% warfarin baited plots, respectively, indicating the absence of pigs was a result of toxic bait consumption. Results of 97 systematic searches of the treatment plots indicated no warfarin-induced non-target wildlife fatalities. Warfarin residues in wild pig livers averaged 3.69 mg/kg (n = 13) and 2.89 mg/kg (n = 9) for pigs recovered within the 0.005% plot and 0.01% warfarin plot, respectively. This study is the first efficacy field evaluation of a wild pig toxicant conducted in the US. The results suggest low-dose warfarin bait, presented in species-specific feeders, can effectively reduce wild pig numbers and pose minimal risk to non-target wildlife and domestic animals. A product containing warfarin may provide another management tool in reducing wild pig problems.

show abstract

“…Camera trapping rate is defined as the ratio between the encounter rate, i.e., the total number of photographic events y and the camera trapping effort t , i.e., the number of 24-h periods each camera was deployed. To ensure independency between subsequent event records, we only used consecutive camera capture events (i.e., visiting individuals or groups of wild boar) with a minimum of 10-min interval between records ( 32 ). This resulted in the removal of 197 records from the full dataset comprising 2,089 records.…”

Section: Methodsmentioning

confidence: 99%

Disease-Induced Mortality Outweighs Hunting in Causing Wild Boar Population Crash After African Swine Fever Outbreak

et al. 2020

View full text Add to dashboard Cite

African swine fever (ASF) has been spreading in the Eurasian continent for more than 10 years now. Although the course of ASF in domestic pigs and its negative economic impact on the pork industry are well-known, we still lack a quantitative assessment of the impact of ASF on wild boar (Sus scrofa) populations under natural conditions. Wild boar is not only a reservoir for ASF; it is also one of the key wildlife species affecting structure and functioning of ecosystems. Therefore, knowledge on how ASF affects wild boar populations is crucial to better predict ecosystem response and for the design of scientific-based wild boar management to control ASF. We used a long-term camera trap survey (2012-2017) from the Białowieza Primeval Forest (BPF, Poland), where an ASF outbreak occurred in 2015, to investigate the impact of the disease on wild boar population dynamics under two contrasting management regimes (hunted vs. non-hunted). In the hunted part of BPF ("managed area"), hunting was drastically increased prior and after the first ASF case occurred (March 2015), whereas inside the National Park, hunting was not permitted ("unmanaged area," first detected case in June 2015). Using a random encounter model (REM), we showed that the density and abundance of wild boar dropped by 84 and 95% within 1 year following ASF outbreak in the unmanaged and managed area, respectively. In the managed area, we showed that 11-22% additional mortality could be attributed to hunting. Our study suggests that ASF-induced mortality, by far, outweighs hunting-induced mortality in causing wild boar population decline and shows that intensified hunting in newly ASF-infected areas does not achieve much greater reduction of population size than what is already caused by the ASF virus.

show abstract

Camera traps and activity signs to estimate wild boar density and derive abundance indices

Cited by 39 publications

References 58 publications

The risk of foot-and-mouth disease becoming endemic in a wildlife host is driven by spatial extent rather than density

The risk of foot-and-mouth disease becoming endemic in a wildlife host is driven by spatial extent rather than density

Field evaluation of low-dose warfarin baits to control wild pigs (Sus scrofa) in North Texas

Disease-Induced Mortality Outweighs Hunting in Causing Wild Boar Population Crash After African Swine Fever Outbreak

Contact Info

Product

Resources

About