Do Feed Plants Provide Sufficient Sodium, Calcium and Magnesium to Sika Deer in Japan? An Analysis Using Global Plant Trait Data

SIMPLE SUMMARY: Selective culling of female deer is effective in reducing overabundant sika deer (Cervus nippon) populations. Sodium (Na), calcium (Ca) and magnesium (Mg) can act as an attractant to selectively cull female sika deer due to the differences in mineral requirements. Here, using global plant trait data and a published list of sika deer feed plants in Japan, we estimated whether feed plants provide sika deer sufficient Na, Ca and Mg, and compared the results between males and females. Our analysis showed that sufficient Na and Ca were not always provided, especially when intakes were low and deer were large. Na deficiency was more intense for lactating females than males, whereas Ca deficiency was more intense for males. We suggest that Na and Ca could be useful for developing effective culling methods. Especially, Na could be useful for selective culling of female sika deer during the lactating period. ABSTRACT: Deficient minerals in overabundant populations could act as an attractant to cull sika deer (Cervus nippon). Because selective culling of female deer is reported to be effective in reducing sika deer populations, it is particularly important to clarify the differences in mineral requirements between males and females. Here, using global plant trait data and a published list of sika deer feed plants in Japan, we estimated whether feed plants provide sika deer sufficient sodium (Na), calcium (Ca) and magnesium (Mg), and compared the results between males and females. An analysis of 191 feed plant species suggested that feed plants can provide sufficient Mg, whereas sufficient Na and Ca is not always provided, especially when the intake is small or the deer large. Na deficiency was more intense for lactating females than males, suggesting that Na can be an effective attractant for selectively culling female deer. In summary, this study demonstrated that sika deer in Japan might require extra Na and Ca sources in addition to feed plants, and therefore these minerals could be useful for developing effective culling methods.