Cache like a squirrel: analysis of and recommendations for long-term storage of white oak (Quercus alba) and pin oak (Q. palustris) acorns for use in wildlife rehabilitation without fat degradation
DOI:
https://doi.org/10.53607/wrb.v42.266Keywords:
diet, nutrition, degradation, quality, acorns, fatAbstract
Several wild animal species include acorns from white oak (Quercus alba), a species from the white oak section, Quercus, and pin oak (Q. palustris), a species from the red oak section, Lobatae, as a diet staple, particularly during preparation for winter. Acorns provide a natural, easily gathered food for wildlife recovering in rehabilitation facilities, but long-term storage can be challenging. The authors examined whether the nutritional value of acorns measured as crude fat deteriorates under temperature-controlled drying and storage methods. Fat content was assayed from 14 trees (six white oak, eight pin oak) immediately after collection (baseline) and compared to fat content after one month and six months of storage for both species. Storage at 4°C (40°F, refrigerator) resulted in the germination of some white oak acorns and mold growth in both species. Although acorns from pin oaks had significantly more fat than white oak acorns at baseline, drying, storage, and combination treatments resulted in no significant difference in fat content, as measured by effect size, for either species. The study results suggest that acorns cached by species like squirrels (Sciurus spp.) do not vary significantly in fat content when recovered one or six months later compared to acorns consumed directly from the trees. The authors recommend wildlife rehabilitators store acorns either in the freezer or at room temperature depending on their storage capabilities.
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