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Published on: November 16, 2014
Food processing by animals: do beavers leach tree bark to improve palatability?
D Müller-Schwarze1, H Brashear, R Kinnel
1SUNY College of Environmental Science and Forestry, Syracuse, New York, USA. dmullers@mailbox.syr.edu
Journal of Chemical Ecology
|July 27, 2001
Summary
Beavers soak tree branches in water to make them more palatable by leaching out undesirable compounds. This study shows beavers utilize aquatic environments to process food, particularly witch hazel (Hamamelis virginiana).
Area of Science:
- Ecology
- Animal Behavior
- Biochemistry
Background:
- Beavers (Castor canadensis) are known to store and consume woody plant material in aquatic environments.
- The palatability of food sources can be influenced by the presence of undesirable chemical compounds.
Purpose of the Study:
- To investigate whether beavers soak tree parts in water to leach out undesirable compounds, thereby increasing food palatability.
- To determine the optimal soaking time and species-specific differences in this food processing behavior.
Main Methods:
- Multiple experiments involved soaking red maple (Acer rubrum) and witch hazel (Hamamelis virginiana) saplings/twigs in natural and laboratory water settings for varying durations.
- Soaked and unsoaked plant materials were offered to free-ranging beavers, and consumption patterns were recorded.
- Phenolic compound leaching from red maple twigs and bark was quantified after soaking.
Main Results:
- Soaking red maple for two days slightly increased its acceptability to beavers.
- Witch hazel consumption varied by location and soaking time, with some evidence suggesting preference after two days of soaking.
- Significant leaching of phenolic compounds occurred from red maple twigs (70-80%) and bark (50-60%) after soaking.
Conclusions:
- Beavers appear to utilize aquatic environments to leach undesirable compounds from their food sources, potentially enhancing palatability.
- While the effect was not consistently robust across all species and conditions, this study provides the first evidence for this beaver foraging strategy.
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