| Summary: | Nitrogen acquisition by Greater White–fronted and Bean geese from late autumn to early spring, was studied in Japan. Samples of food plants were collected from eight major locations throughout late autumn 2005 to early spring 2006, and analyzed for nitrogen content. Major food sources were waste rice grains, post-harvest soy beans and corn and secondary rice stems, together with several wild grasses and barley/wheat sprouts growing on rice fields. The nitrogen content of food species eaten by the geese just prior to spring migration was considered sufficiently high for their needs, being comparable to plant nitrogen contents documented from the Arctic breeding areas. The analysis indicates the potential importance of food source nitrogen as a criterion for site selection during migration and wintering. The importance for the geese of being able to eat foods with high nitrogen content following a long–distance migration is discussed on the basis of existing references. journal article
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