Abstract
We investigated the relationship between the fruit phenology of Prunus jamasakura and the fruit-feeding period of the Asiatic black bear (Ursus thibetanus). The purposes of this study were to determine (1) when bears feed on the fruit of P. jamasakura in relation to phenology; (2) whether ingestion damages seeds; and (3) how ingestion influences seed germination. We assessed the relationship between the phenology of fruit maturation (size, sugar concentration, color, persistence, and germination percentage) and the feeding period of bears in the field, as judged from bear shelves and claw marks. We also compared the germination percentage of seeds ingested by captive bears with that of uningested. Bears fed on the fruit from days 50 to 66 after flowering, when most of the fruits were on the tree and became large, the germination percentage of seeds increased, and the sugar concentration became high. Bears fed only on mature fruits and so obtained high-quality nutrients. Germination tests showed that ingestion of fruits by the bears caused no physical damage to the seeds. Ingested seeds did not show a significant difference in germination percentage from seeds, whose pulp was artificially removed. These results indicate that bears are potentially effective dispersers from a qualitative perspective and, to some extent, from a quantitative perspective.
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Acknowledgments
We are grateful to T. Hazumi for his gracious cooperation. We also thank T. Komatsu, A. Izumi, T. Izumi, and M. Suzuki, who gave much useful advice about the feeding studies at Ani. We wish to thank T. Masaki for his helpful advice. We also would like to express our appreciation to M. Kitahara, Z. Jiang, and H. Ueda. Thanks are offered to N. Tokita for help with the sugar analysis. Part of the preliminary examination was carried out at the Yokohama Zoological Gardens. This work was partly supported by Ani Town, a Sasakawa Scientific Research Grant from the Japan Science Society, and the Nature Conservation Society of Tanzawa.
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Koike, S., Kasai, S., Yamazaki, K. et al. Fruit phenology of Prunus jamasakura and the feeding habit of the Asiatic black bear as a seed disperser. Ecol Res 23, 385–392 (2008). https://doi.org/10.1007/s11284-007-0399-3
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DOI: https://doi.org/10.1007/s11284-007-0399-3