With 20 fish antennas deployed across three watersheds, the real fun begins! In order to track fish movement, these fish tracking antennas only work if the fish pass through sporting a passive integrated transponder (PIT) tag, which requires us to do some serious fishing. We pull out all the stops this week, using fyke nets, dip nets, seines, spinning rods and fly rods to capture Arctic grayling large enough to tag with PIT tags. Each fish we catch initiates into our study with the ritualistic measuring of length and weight, plus the newly traditional genetic sample fin clip, all of which provide us with valuable demographic and population information. Starting half-way up Oksrukuyik Creek, our fyke nets and seine capture all size classes of one species, the Arctic grayling, from young-of-the-year (YOY) to adults. But, shifting our fishing efforts to the lower Oks reveals surprising species variety, perhaps due to the creek’s proximity here to the larger waters of the Sagavanirktok River into which the Oks flows. As we travel from Toolik Field station to our study sites on Oks Creek, we spot rainbows and gryfalcons along the Haul Road. Although the road might provide perches and meals for the falcons, there are trade-offs as well. After spotting them alive one day, we found both falcons dead on the road the next, likely hit by trucks. The rainbows bear only good tidings, as much needed moisture permeates the parched tundra, hopefully filling our dried river beds and once again facilitating fish movement through the aquatic landscape. Helped by Toolik staff, construction crew members, and a helicopter pilot, we’ve now caught and processed over 130 fish in the Oks, with 66 Arctic grayling large enough to hold PIT tags.
Fish holding bags dry on the Lab3 railing, poised for tomorrow’s action.
My summer Fishscape crew helps set back-to-back fyke nets, both to capture fish and to estimate fish movements, whether upstream or downstream.
This Arctic grayling, caught on a dry mayfly imitation, thinks hard about making a get-away.
Always a surprise, opening a fyke net is like opening a birthday present. Here, Tom measures the round whitefish we trapped along with Arctic grayling and char and one tiny, slimy sculpin. Quite a variety pack!
Surprise! Arctic char and a slimy sculpin are among the assortment of fish caught in our fyke net in lower Oksrukuyik Creek.
One of two gyrfalcons seen alive and well on the Dalton highway only yesterday. Tragically, both were found dead on the road today.
Always a wonder to behold, these rainbows usher in desperately needed rain to the parched North Slope.
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