To determine the optimal time for releasing chum salmon into the Gakko River, otolith-marked juveniles reared to more than 1 g body mass were released in late February, mid-March, and late March of 2009 to 2011. Although factors that determine return rates are yet unknown, the return rates were highest for the mid-March (0.62ô-1.02ô) groups of all three brood years. Return rates for the late February and late March groups were approximately half that of the mid-March groups. These results suggest that releasing chum salmon in mid-March is optimal for increasing return rates.
|Translated title of the contribution||Comparison of return rates of chum salmon Oncorhynchus keta released at various times into the Gakko River, Yamagata Prefecture, Japan|
|Number of pages||4|
|Publication status||Published - 2018|
ASJC Scopus subject areas
- Aquatic Science
- Animal Science and Zoology