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Contrafreeloading in grizzly bears: implications for captive foraging enrichment
Ragen T S McGowan1, Charles T Robbins, J Richard Alldredge
1Center for the Study of Animal Well-being, Department of Animal Sciences, Washington State University, Pullman, Washington, USA. Ragen.Trudelle-SchwarzMcGowan@rdmo.nestle.com
Zoo Biology
|October 10, 2009
Summary
Contrafreeloading, where animals work for food available freely, can be a valuable foraging enrichment strategy for captive wildlife. Studies with grizzly bears show they engage in contrafreeloading, suggesting its potential for improving animal welfare.
Area of Science:
- Animal Behavior
- Wildlife Enrichment
- Zoo Nutrition
Background:
- Traditional captive animal feeding focuses on physiological needs.
- Foraging enrichment is common in zoos but risks nutrient imbalance.
- Contrafreeloading offers a potential solution by providing effort-based feeding opportunities.
Purpose of the Study:
- To investigate contrafreeloading behavior in captive grizzly bears.
- To assess the potential of contrafreeloading as a foraging enrichment strategy.
- To understand how food restriction affects contrafreeloading.
Main Methods:
- Two experiments were conducted with captive grizzly bears (Ursus arctos horribilis).
- Bears were offered choices between freely available food and food requiring effort (e.g., in ice or boxes).
- Measures included food consumption and time spent working for food.
Main Results:
- Bears consumed more free food than earned food in both experiments.
- Bears spent more time manipulating food presented with effort (in ice or boxes) than plain items.
- Food restriction levels did not significantly alter time spent working for food.
Conclusions:
- Contrafreeloading opportunities can be successfully provided to captive grizzly bears.
- This paradigm supports foraging enrichment strategies for captive wildlife.
- Contrafreeloading may enhance animal welfare by promoting natural feeding behaviors.
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