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

Cheyenne T. Villarosa; Sabrina N. Volponi; Tamara L. Johnstone-Yellin

doi:10.53607/wrb.v42.266

Authors

Cheyenne T. Villarosa Virginia-Maryland College of Veterinary Medicine at Virginia Tech, Blacksburg, VA, USA
Sabrina N. Volponi Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN, USA
Tamara L. Johnstone-Yellin Department of Biology and Environmental Science, Bridgewater College, Bridgewater, VA, USA https://orcid.org/0009-0009-3597-7405

DOI:

https://doi.org/10.53607/wrb.v42.266

Keywords:

diet, nutrition, degradation, quality, acorns, fat

Abstract

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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Author Biographies

Cheyenne T. Villarosa, Virginia-Maryland College of Veterinary Medicine at Virginia Tech, Blacksburg, VA, USA

Cheyenne Villarosa graduated from Bridgewater College in 2022 with a BS in biology with an emphasis in wildlife biology. She is a current student at Virginia-Maryland College of Veterinary Medicine at Virginia Tech pursuing her DVM.

Sabrina N. Volponi, Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN, USA

Sabrina Volponi graduated from Bridgewater College in 2020 with a BS in environmental science and mathematics. She completed her PhD in Civil and Environmental Engineering and Earth Sciences at the University of Notre Dame in 2024, modeling environmental flows through fractured and porous media. She is currently a postdoctoral researcher at Washington State University, exploring transport through rivers and biofilms.

Tamara L. Johnstone-Yellin, Department of Biology and Environmental Science, Bridgewater College, Bridgewater, VA, USA

Tamara Johnstone-Yellin (she/her) is a wildlife ecologist and associate professor in the Department of Biology and Environmental Science at Bridgewater College. She completed her Master of Science and doctorate at Washington State University’s Department of Natural Resources. Her research focuses on the nutritional ecology of mammalian herbivores.

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