3 RESULTS
3.1 Seasonal migration timing of Sakhalin
taimen
In 2018, a total of 105 PIT-tagged Sakhalin taimen spawners returned to
the Karibetsu River, including 90 fish tagged that year. In 2019, 76
tagged spawners returned, of which 73 had also returned in 2018 (i.e.
consecutive repeat spawners). During the period of upstream migration,
water temperature increased monotonically, while water level varied more
stochastically but decreased substantially by the time spawners arrived
at Site L (Fig. S1).
3.2 Between-year consistency in migration
timing
The chronological order of individual Sakhalin taimen arriving or
departing during each MS was remarkably consistent between 2018 and 2019
as evidenced by an apparent tendency of lines connecting the same
individuals in these two years to be parallel to one another (Fig. 2).