Manipulating Beaver (Castor canadensis) Feeding Responses to Invasive Tamarisk (Tamarix spp.)

• Published in: Journal of chemical ecology 2008-08, Vol.34 (8), p.1050-1056
• Main Authors: Kimball, Bruce A, Perry, Kelly R
• Format: Article
• Language: English
• Subjects: Agriculture; Animal and plant ecology; Animal, plant and microbial ecology; Animals; antifeedants; Aquatic mammals; Beavers; Behavior Control - methods; Biochemistry; Biological and medical sciences; biological control agents; Biological Microscopy; Biomedical and Life Sciences; browsing; Carbohydrates - chemistry; casein hydrolysates; Castor canadensis; Cuttings; Diet; Ecology; Entomology; experimental diets; Feasibility Studies; Feeding Behavior - physiology; feeding preferences; Flowers & plants; food plants; foraging; foraging preference; Fundamental and applied biological sciences. Psychology; General aspects; Life Sciences; Mammalia; palatability; Plant species; Polyethylene Glycols - chemistry; Preferences; Riparian ecology; Rodentia - physiology; Salt; Sodium chloride; Studies; Tamaricaceae; Tamarix; tannins; Taste; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution
• ISSN: 0098-0331; 1573-1561
• DOI: 10.1007/s10886-008-9496-1

To evaluate methods for promoting consumption of tamarisk plants by beavers (Castor canadensis), we determined the feeding responses by captive beavers to diets that contained tannins and sodium chloride (hereafter referred to as tamarisk diet). In two-choice tests, beavers consumed equivalent quantities of tamarisk diet and control diet. Treatment with polyethylene glycol and fructose did not increase beaver preferences for the tamarisk diet. When offered the choice of control diet and casein hydrolysate-treated control diet, beavers strongly avoided the latter, showing feeding deterring activity of casein hydrolysate. However, when tamarisk diet was the alternative to the deterrent treatment, beavers consumed similar quantities of the two diets. Finally, beaver foraging preferences for actual plant cuttings were assessed. Casein hydrolysate application to cuttings of black poplar (Populus nigra) and Scouler's willow (Salix scouleriana) reduced browsing of these highly preferred species and promoted a marked increase in browsing of tamarisk (Tamarix ramosissima). These results suggest that casein hydrolysate treatment of desirable riparian plant species such as Salix and Populus may promote beaver foraging of invasive tamarisk.