As much needed rain fell steadily through the night and into the day, thirsty plants on the dehydrated landscape slurped up the water almost as fast as it fell. This rapid evapo-transpiration by the plants prevented most of the newly fallen water from reaching the streams, such that river water levels remained uncharacteristically low. Within this context, the Fishscape team turned efforts toward assessing fish habitat and young-of-the-year Arctic grayling abundance along rivers within our three study watersheds. Starting in the I-Minus outlet stream, we measured factors including substrate, river depth and width, nutrients, primary production, aquatic invertebrates, stream side vegetation and, of course, fish abundance. Our habitat and fish abundance data will help identify parameters defining critical habitats, such as spring spawning and summer feeding locations, for Arctic grayling. Bobbing about the tussocks in our multi-colored rain gear, we wondered if PBS might consider an Arctic twist to their children’s programming? Look out Teletubbies, the Tundratubbies have arrived! First, however, we might need to change our Habitat Assessment’s nickname.
Smiling through the downpour, Tom (a.k.a. Tundratubbie Po) readies dip nets to assess larval fish abundance in the I-Minus outlet stream.
More Tundratubbies!! Dan and Becca scrub epilithic algae and aquatic invertebrates off rocks to estimate primary and secondary benthic stream productivity.
Who would have guessed “gravelometry” is a “thing?” Fitting rocks inside a gravelometer, seen here, helps gauge substrate composition as a factor associated with fish habitat use.
Using a large seine and dip nets, we find both young-of-the-year and adult Arctic grayling in this stretch of the I-Minus outlet stream, along with one lonesome round whitefish.
Back at Toolik Field Station, by 2 a.m. all samples have been properly preserved and stored, the helicopter flight plan has been submitted and our gear lies re-staged and ready for tomorrow’s habitat assessment (Hab. Ass. for short).
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