Effects of a GnRH vaccine on the movement and activity of free-living wild boar (Sus scrofa)

Abstract

Context. Fertility control is being promoted as a non-lethal means of managing wildlife populations. We recently evaluated a single-dose injectable immunocontraceptive vaccine (GonaConÔ) on captive female wild boar for effectiveness and potential side effects; reproductive output was inhibited for 4-6 years, with no obvious detrimental effects on physiology and behaviour.Aims. We injected individual free-living wild boar individuals with the fertility-control vaccine GonaConÔ to examine its effectiveness (measured as raised levels of GnRH antibodies) and looked for potential changes in movement and activity patterns.Methods. We trapped, fitted telemetry devices to, and released wild boar individuals living in woodland in the West Midlands region of England between 2006 and 2010. We compared data on movements and activity among 10 adult females treated with the vaccine and 11 controls treated with saline only. We measured anti-GnRH antibody titres in six recaptured boar individuals as an indicator of the effectiveness of the vaccine.Key results. Post-treatment GnRH antibody titres varied among the boar individuals; four of five treated sows resampled between 9 and 30 weeks post-injection had antibody titres high enough to block reproduction (detectable at 1 : 32 000-1 : 64 000 dilution). At least three treated females were pregnant at the time of vaccination; there was no subsequent evidence that the vaccine interfered with pregnancy. According to the distances moved per hour over a 24-h cycle and the daily activity cycle in relation to season, there were no differences in the behaviour of treated and control females that were likely to be biologically significant. The behaviour of two treated females monitored soon after vaccination and again 12 months later also showed no major differences.Conclusions. Free-living wild boar responded to treatment with a 1.0-mL (1000 mg) dose of an anti-GnRH vaccine and no major adverse effects on activity and movement were subsequently detected.Implications. Our results indicated that the vaccine could be more widely evaluated in the field against overabundant or nuisance populations. Such populations are increasingly found in urban areas and parks, where culling may not be an option. We suggest that further refinement of this approach for managing wild boar populations, including development of an oral vaccine, are warranted.

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

“…We treated all five sites as independent from each other, i.e. with minimal or no movement of wild boar between sites, as previous information from radio tracking showed that wild boar monthly movements in this area were generally restricted to individual woods . The distance between adjacent woods was measured by the distance of the closest point of each wood edge to the other: Penyard/Chase to Serridge, 5.7 km; Serridge to Oakenhill, 7.2 km; Beckley/Bixley to Brede, 3.2 km.…”

Exact Bayesian inference for animal movement in continuous time

“…The wild boar data set is described in detail in Quy et al . (); the extract used here is available at Blackwell et al . ().…”

“…Our second example uses part of an extensive data set on wild boar Sus scrofa, collected by the Animal and Plant Health Agency's National Wildlife Management Centre (formerly part of the Food and Environment Research Agency) to investigate the possible side effects of immunocontraceptive vaccines (Quy et al 2014). Animals were tracked using GPS collars, with fixes every 15 or 30 min (night/day).…”

“…The full fisher data set is available at LaPoint et al (2013b); the extract used here is included with the code in Appendix S4. The wild boar data set is described in detail in Quy et al (2014); the extract used here is available at Blackwell et al (2015).…”

Development of Perception Test for Human-Wildlife Conflict

“…The common wildlife encountering with humans are elephant, wild boar, and primates. Overabundant wild boar and feral pigs are associated with disease transmission and negative impacts on agriculture, native Wildlife and, particularly where they occur around urban areas, public safety (Quy et al, 2014). Crop raiding was found to be predominantly directed at maize and perceived at least to be carried out solely by primates (Mc Guinness and Taylor, 2014).…”