If you've been following this issue, you know that predation by trout has been blamed, at least in part, for the decline of an endangered species endemic to the High Sierra known as the yellow legged frog. Trout have been removed from a few high country lakes within the national parks in order to give this species a chance to recover.
Are trout to blame? A new study indicates that there may be a more important factor, a disease carried by the Pacific Chorus Frog.
The Chytrid disease is a water-borne fungus, so scientists assumed it would spread downstream through rivers and lakes. But in the Sierra Nevada, the epidemic moved uphill. The chorus frog is probably the reason, says a San Francisco State researcher, Natalie Reeder.
"These frogs can climb mountains and go places that are pretty dry," she said. They carry with them the nasty disease that kills other frogs.
You can read more about the study here:
This is something to keep in mind when the issue of planting and of removing trout from alpine lakes comes up.