<p>These Yellowstone cutthroats have swum up the Lamar River drainage to deposit their eggs in the gravel of a streambed. This spring and early summer spawning pilgrimage makes the fish vulnerable to predators like eagles, bears, and otters.</p><p>Native Yellowstone cutthroats (<em>Oncorhynchus clarkii bouvieri</em>) <a href="http://news.nationalgeographic.com/news/2013/1/130122-lake-trout-lake-yellowstone/">have recently faced a new enemy in the form of invasive&nbsp;lake trout</a> (<em>Salvelinus namaycush</em>), which are larger fish that prey on them.</p><p><em>—Cathy Newman</em></p>

Yellowstone Cutthroat Trout

These Yellowstone cutthroats have swum up the Lamar River drainage to deposit their eggs in the gravel of a streambed. This spring and early summer spawning pilgrimage makes the fish vulnerable to predators like eagles, bears, and otters.

Native Yellowstone cutthroats (Oncorhynchus clarkii bouvieri) have recently faced a new enemy in the form of invasive lake trout (Salvelinus namaycush), which are larger fish that prey on them.

—Cathy Newman

Photograph by Jay Fleming

Pictures: Trout vs. Trout in Yellowstone Lake

Things were going swimmingly for Yellowstone cutthroats, a species of trout native to Wyoming’s Yellowstone Lake. Then someone added a few non-native lake trout to the mix.

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