Pictures: Trout vs. Trout in Yellowstone Lake

Lake Trout Eggs

Photograph by Jay Fleming

For invasive lake trout in Yellowstone Lake conditions are ideal, including the presence of a bottom surface optimal for depositing eggs. Here, a type of crustacean called a scud nestles between a rock and lake trout eggs. The translucent yellow eggs are viable; the white eggs are not.

Published January 22, 2013

Netting Invaders

Photograph courtesy Jay Fleming, NPS

Without aggressive management, the population of Yellowstone cutthroats could be decimated. To suppress the population of lake trout, the National Park Service engaged a contract fishing company to net them. Cutthroats are removed carefully from the traps and thrown back. Lake trout are removed and killed. Last year about 300,000 of the non-native intruders were taken from the lake.

Published January 22, 2013

Trout Transmission

Photograph courtesy Jay Fleming, NPS

Beginning in 2011, transmitters were surgically implanted in more than 200 lake trout. It is hoped the research will allow biologists to pinpoint spawning grounds in order to increase the success of suppression efforts.

Published January 22, 2013

Fish out of Water

Photograph courtesy Jay Fleming, NPS

Kevin Osantowski, a fisheries technician with the environmental group Yellowstone Coalition, holds a lake trout netted on a National Park Service boat. Lake trout outweigh and outlive cutthroats. They also prey on their smaller cousins and one lake trout can consume some 40 cutthroats in the course of a year.

Published January 22, 2013

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Photograph by David Doubilet, National Geographic

Published January 22, 2013