Bait consumption by, and 1080-based control of, feral pigs in the Mediterranean climatic region of south-western Australia

Abstract

The consumption of five non-toxic, grain-based baits, and the effectiveness of the preferred baits when treated with 1080 in reducing pig numbers, were determined for feral pigs (Sus scrofa) in several areas in the Mediterranean agricultural region of Western Australia. Fermented wheat with added blood and bone proved an effective attractant for feral pigs, and for determining areas of pig activity. Wheat and malted barley were the preferred baits, there was a variable response to lupins, and commercial pig pellets were consumed least. Malted barley, barley, and wheat treated with 1080 gave good reductions in pig numbers at the localised scale. Where pigs would eat lupins, 1080-treated lupins were usually effective in reducing pig abundance. In some instances, further evidence of feral pig activity was not seen on several sites for several months after poison-baiting occurred. The addition of a small amount of unpoisoned grain to mask the presence of 1080 did not increase the take of treated bait (P < 0.05). Although finding poisoned pigs was difficult owing to the terrain and the presence of bush remnants, the poisoned pigs found (n = 90) were often within 200 m of active bait stations. 1080-poisoned pigs included both adult (≥25 kg) and non-adult pigs of both sexes. Body mass of these pigs ranged from 4 to 90 kg. In all, 42% of poisoned adults found (n = 50) were 50 kg or more. There was minimal evidence of bait take by non-target species, and, where this occurred, it generally involved the consumption of the fermented wheat attractant by kangaroos (Macropus spp.) and foxes (Vulpes vulpes). Six foxes were known to have been poisoned with 1080-treated grain (4 with malted barley, 2 with wheat). Excluding foxes, no other non-target animals, including native species, were found dead during the intensive searches for poisoned pigs.

Feral swine damage and damage management in forested ecosystems

“…This research was subsequently augmented by studies on free-ranging feral swine, including bait uptake and consumption studies (McIlroy et al, 1993;Choquenot and Lukins, 1996), compound 1080 intake , risk assessments to non-target animals (McIlroy, 1992;Twigg et al, 2005a), the effectiveness of ground baiting campaigns with compound 1080 (Hone and Pedersen, 1980;Hone, 1983;Twigg et al, 2005b;Cowled et al, 2006a;Twigg et al, 2006Twigg et al, , 2007 and warfarin McIlroy and Saillard, 1989;Saunders et al, 1990;Choquenot et al, 1990), and the effectiveness of aerial baiting campaigns (Mitchell, 1998;Fleming et al, 2000). Compound 1080 and warfarin have also been used to eradicate feral swine from Santiago Island in the Galá pagos archipelago, Ecuador (Coblentz and Baber, 1987;Cruz et al, 2005).…”

Simulation of Wild Pig Control via Hunting and Contraceptives

“…One study found that the maximum distance between points visited on a given day was, on average, 0.4 miles for sounders and 0.7 miles for boars. These extremes in daily position depended on the availability of food and water (Kavanaugh and Linhart 2000;Twigg et al 2007). Despite ample data regarding habitat preferences and range, specific daily movements of feral pigs are difficult to predict.…”

Selective piglet feeders improve age-related bait specificity and uptake rate in overabundant Eurasian wild boar populations

“…In Spain, the use of lethal means other than shooting to control wild boar damage and diseases is not allowed. Along with hunting, livetrapping and habitat management, both wild boar and feral-pig control has been carried out with baits containing either poison (McIlroy et al 1989;Saunders et al 1990;Cowled et al 2006;Twigg et al 2007) or contraceptives (Linhart et al 1997).…”