Our poster outlines proposed research to assess energetic budgets of juvenile salmonids in a
mining-impacted stream. Our study site is located at Coal Creek, a tributary of the Yukon River
in Yukon-Charley Rivers National Park and Preserve in Alaska. This stream is scheduled for
restoration in 2026 with the goal of increasing habitat for juvenile Chinook salmon
(Oncorhynchus tshawytscha). This work is especially important in the context of the current
collapse in Yukon River Chinook salmon populations. This collapse has had not only effects on
ecosystem health, but also an outsized impact on the local Indigenous people who rely on salmon
for subsistence. In fish, juvenile life stages are critical for development due to pressures from
high intraspecific competition and predation. Therefore, it is necessary to demonstrate how
mining-induced alterations to habitat impact growth potential for juvenile salmonids. Because
salmon are limited in their access to prey by gape size they must grow rapidly to access larger,
more energetically dense prey. We hypothesize that the impacted conditions in Coal Creek,
principally redistribution of the stream into a novel channel dominated by mine tailings, is
associated with slower growth rates in juvenile salmonids. Subsequently, we predict that total
production of the macroinvertebrate community will be lower in Coal Creek than in adjacent,
unmined reference streams, with concomitant impacts on salmonid growth rates between these
streams. To test our predictions, we will quantify and characterize the macroinvertebrate
community in each stream. Then, using macroinvertebrate production and temperature data we
will develop and parameterize a bioenergetics model to generate a growth curve for juvenile
salmonids in both Coal Creek and reference streams. This work will allow us to compare fish
growth rates with maximum macroinvertebrate densities and determine if changes in ontogeny
are limiting growth potential.