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Understanding migration ecology of Eurasian wigeons ( Mareca penelope ) is crucial for effective population management, mitigating conflicts with human, and habitat conservation. The objectives of the present study were 1) to determine their migration patterns of Eurasian wigeons in the East Asian flyway, and 2) to identify the key breeding and stopover sites. From 2007 to 2016, a total of the 64 wigeons, which wintered in Japan, were equipped with satellite transmitters. Most Eurasian wigeons migrated to breeding sites in Russia either (a) via a continental route through China, (b) via the Kamchatka Peninsula, or (c) via Sakhalin Island. In spring, many of the Eurasian wigeons (60.98%) migrated via the continental route. In autumn, most Eurasian wigeons (57.14%) migrated through Kamchatka. These differences may be attributable to the influence of Okhotsk Sea air mass on migration decisions due to loop migration. Similarly to the migration of Mallards, Eurasian wigeons employed a "long-stay and short-travel" migration strategy. Eurasian wigeons mainly nested between latitude between 43° to 75°N. From the present findings and the published literature, Eurasian wigeons that winter in Japan are considered to migrate to Russia, China, and the United States during the breeding season, although the main breeding area is in northeastern Russia. A total of 296 important sites to Eurasian wigeons were mapped, and 118 location names with geographic coordinates, and the top five most frequently used sites were identified in each season.

Objectives: The effects of 3 months of desert travel in China on serum fatty acids and tocopherol were studied., Methods: In project staff members (6 males, 3 females, aged 19-27 years), serum levels of fatty acids and alpha-tocopherol were analyzed before and after travel by gas liquid chromatography and high-performance liquid chromatography, respectively., Results: Comparison of the levels before and after the trip showed no differences in serum total cholesterol, triglycerides, total protein or alpha-tocopherol. There were no changes in the levels of total fatty acids, while the percentage of polyunsaturated fatty acids increased (p < 0.05). Levels of n-3 PUFA lowered from 166 micrograms/ml to 103 micrograms/ml, and those of n-6 PUFA had increased from 988 micrograms/ml to 1140 micrograms/ml after the trip (p < 0.01 and p < 0.001, respectively). No change was observed in the serum levels of alpha-linolenic acid (C18:3n-3), but lowering of the levels of eicosapentaenoic acid (EPA, C20:5n-3) from 41.4 micrograms/ml to 16.3 micrograms/ml and docosahexaenoic acid (DHA, C22:6n-3) from 107.8 micrograms/ml to 71.7 micrograms/ml was found after the trip (p < 0.05 and p < 0.01, respectively). Serum levels of linoleic acid (LA, C18:2n-6) increased from 832 micrograms/ml to 598 micrograms/ml (p < 0.001), and arachidonic acid (AA, C20:4n-6) tended to increase. The ratios of n-3/n-6 PUFA and EPA/AA decreased from 0.171 to 0.091 and from 0.258 to 0.096 after the trip, respectively (p < 0.01 for both)., Conclusions: Our findings indicated that 3 months of desert travel increased the serum levels of n-6 PUFA and LA and reduced the serum levels of n-3 PUFA and EPA and the ratios of n-3/n-6 PUFA and EPA/AA, possibly due to a relative essential fatty acid deficiency.