Evaluation of Conditioned Taste Aversion as a Method to Reduce Predation of Wildlife Eggs by Feral Pig (Sus scrofa)

Ricardo F Tapilatu, Emma Guyris, Jim Mitchell

Abstract


Feral pigs are introduced predators to Australia and New Guinea. Predation by feral pigs on eggs and hatchlings of nationally protected sea turtles and other wildlife can cause significant mortality. Several control techniques are available to minimize pig predation but available techniques are expensive and of limited success. A potential method is to teach feral pigs to avoid predating eggs by using Conditioned Taste Aversion (CTA). In this study, it was hypothesized that if eggs were treated with deterrent chemicals, feral pigs would develop an aversion to the eggs, and would stop predating them. Sixteen feral pigs were presented with eggs treated with the distasteful chemicals: TBZ and LiCl for 5 consecutive days following a pre-treatment phase during which they were fed untreated eggs. The percentage of eggs predated during the treatment phase was lower than in the pre-treatment phase, though in most cases this difference was not statistically significant. Most eggs predated during the treatment phase were only partly eaten, suggesting that pigs were taste-testing. In addition, pigs consumed similar proportion of untreated eggs and control eggs during the pre-treatment and post-treatment phases.

Thus, taste aversion was not established. In a second experiment, external scent cues were applied to the eggshells. It was hypothesized that the pigs would only consume untreated eggs, and leaves the treated-scented eggs untouched. A new group of 16 feral pigs were presented with scented eggs treated with TBZ and LiCl for 10 consecutive days. The pigs still predated by partly consuming the scented-treated eggs. Similar percentages of untreated and scented-control eggs were predated during the pre-treatment and post-treatment phases. This study failed to provide support for CTA as an effective method of controlling feral pig predation of wildlife eggs.



Keywords


Feral pigs; Conditioned Taste Aversion, TBZ, LiCl, pre-treatment, treatment, post-treatment, untreated, predated

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References


S. E. Stancyk, "Non-human predators of sea turtles and their control," Biology and conservation of sea turtles, pp. 139-152, 1982.

R. J. Hobbs and L. F. Huenneke, "Disturbance, diversity, and invasion: implications for conservation," Conservation biology, vol. 6, pp. 324-337, 1992.

J. D. Waithman, R. A. Sweitzer, D. Van Vuren, J. D. Drew, A. J. Brinkhaus, I. A. Gardner, et al., "Range expansion, population sizes, and management of wild pigs in California," The Journal of wildlife management, pp. 298-308, 1999.

E. K. Schofield, "Effects of introduced plants and animals on island vegetation: examples from Galpagos Archipelago," Conservation Biology, vol. 3, pp. 227-239, 1989.

C. J. Limpus, "The status of Australian sea turtle populations," Biology and Conservation of Sea Turtles. Smithsonian Inst. Press, Washington, DC, pp. 297-303, 1982.

P. M. Vitousek, "Biological invasions and ecosystem processes: towards an integration of population biology and ecosystem studies," in Ecosystem Management, ed: Springer, 1996, pp. 183-191.

A. R. E. Sinclair, R. P. Pech, C. R. Dickman, D. Hik, P. Mahon, and A. E. Newsome, "Predicting effects of predation on conservation of endangered prey," Conservation Biology, vol. 12, pp. 564-575, 1998.

J. Mitchell, Systematic assessment of feral pig damage and recommended pig control methods in the wet tropics World Heritage Area: CSIRO Department of Lands Tropical Weeds Research Centre, 1993.

C. Tisdell, "Feral pigs threaten native wildlife in Australia.," Tiger Paper, vol. 11, pp. 13-18, 1984.

Environment Australia, Draft Recovery Plans for Sea Turtles in Australia, 1998.

D. Choquenot, J. McIlroy, and T. Korn, Managing vertebrate pests: feral pigs: Australian Government Pub. Service, 1996.

C. C. McGaw and J. Mitchell, Feral pigs (Sus scrofa) in Queensland: Land Protection, Department of Natural Resources and Mines, 1998.

M. R. Conover, "Monetary and intangible valuation of deer in the United States," Wildlife Society Bulletin, vol. 25, pp. 298-305, 1997.

M. Conover, "Can waterfowl be taught to avoid food handouts through conditioned food aversions?," Wildlife Society Bulletin, pp. 160-166, 1999.

M. L. Avery and D. G. Decker, "Responses of captive fish crows to eggs treated with chemical repellents," The Journal of wildlife management, pp. 261-266, 1994.

M. R. Conover, "Reducing mammalian predation on eggs by using a conditioned taste aversion to deceive predators," The Journal of wildlife management, pp. 360-365, 1990.

M. A. Lane, M. H. Ralphs, J. D. Olsen, F. D. Provenza, and J. A. Pfister, "Conditioned taste aversion: potential for reducing cattle loss to larkspur," Journal of Range Management, pp. 127-131, 1990.

K. A. Houpt, D. M. Zahorik, and J. A. Swartzman-Andert, "Taste aversion learning in horses," Journal of animal science, vol. 68, pp. 2340-2344, 1990.

M. H. Ralphs, "Persistence of aversions to larkspur in naive and native cattle," Journal of Range Management, pp. 367-370, 1997.

F. D. Provenza, J. J. Lynch, and C. D. Cheney, "Effects of a flavor and food restriction on the response of sheep to novel foods," Applied Animal Behaviour Science, vol. 43, pp. 83-93, 1995.

S. Y. Landau, E. Ben-Moshe, A. Egber, A. Shlosberg, M. Bellaiche, and A. Perevolotsky, "Conditioned aversion to minimize Ferula communis intake by orphaned lambs," Journal of range management, pp. 436-439, 1999.

D. Cornell and J. E. Cornely, "Aversive conditioning of campground coyotes in Joshua Tree National Monument," Wildlife Society Bulletin, pp. 129-131, 1979.

R. J. Burns and G. E. Connolly, "A comment on Coyote control and taste aversion," Appetite, vol. 6, pp. 276-281, 1985.

M. R. Conover, J. G. Francik, and D. E. Miller, "An experimental evaluation of aversive conditioning for controlling coyote predation," The Journal of Wildlife Management, pp. 775-779, 1977.

C. R. Gustavson, "Comparative and field aspects of learned food aversions," Learning mechanisms in food selection, pp. 23-43, 1977.

M. J. Ratnaswamy, R. J. Warren, M. T. Kramer, and M. D. Adam, "Comparisons of lethal and nonlethal techniques to reduce raccoon depredation of sea turtle nests," The Journal of wildlife management, pp. 368-376, 1997.

C. R. Dimmick and L. K. Nicolaus, "Efficiency of conditioned aversion in reducing depredation by crows," Journal of Applied Ecology, pp. 200-209, 1990.

M. A. Ternent and D. L. Garshelis, "Taste-aversion conditioning to reduce nuisance activity by black bears in a Minnesota military reservation," Wildlife Society Bulletin, pp. 720-728, 1999.

C. R. Gustavson, "An experimental evaluation of aversive conditioning for controlling coyote predation: A critique," The Journal of Wildlife Management, pp. 208-209, 1979.

M. R. Conover, "Using conditioned food aversions to protect blueberries from birds: comparison of two carbamate repellents," Applied Animal Behaviour Science, vol. 13, pp. 383-386, 1985.

F. D. Provenza, J. J. Lynch, E. A. Burritt, and C. B. Scott, "How goats learn to distinguish between novel foods that differ in postingestive consequences," Journal of chemical ecology, vol. 20, pp. 609-624, 1994.

M. H. Ralphs, D. Graham, M. L. Galyean, and L. F. James, "Creating aversions to locoweed in naive and familiar cattle," Journal of Range Management, pp. 361-366, 1997.

J. W. Kalat and P. Rosin, ""Learned safety" in mechanism of long-delay taste aversion learning in rats," Journal of Comparative Physiology and Psychology, vol. 83, pp. 198-207, 1973.

J. M. Ziegler, C. R. Gustavson, G. A. Holzer, and D. Gruber, "Anthelmintic-based taste aversions in wolves (< i> Canis lupus)," Applied animal ethology, vol. 9, pp. 373-377, 1983.

F. D. Provenza, J. V. Nolan, and J. J. Lynch, "Temporal contiguity between food ingestion and toxicosis affects the acquisition of food aversions in sheep," Applied Animal Behaviour Science, vol. 38, pp. 269-281, 1993.

E. A. Burritt and F. D. Provenza, "Ability of lambs to learn with a delay between food ingestion and consequences given meals containing novel and familiar foods," Applied Animal Behaviour Science, vol. 32, pp. 179-189, 1991.

L. K. Nicolaus, "Conditioned aversions in a guild of egg predators: implications for aposematism and prey defense mimicry," American Midland Naturalist, pp. 405-419, 1987.

J. Bourne and M. J. Dorrance, "A field test of lithium chloride aversion to reduce coyote predation on domestic sheep," The Journal of Wildlife Management, pp. 235-239, 1982.

F. D. Provenza, "Acquired aversions as the basis for varied diets of ruminants foraging on rangelands," Journal of Animal Science, vol. 74, pp. 2010-2020, 1996.


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