Size matters, for salamanders. Most prefer to reside in the middle of a stream, where the water is deeper and colder. So bigger species often shove the little ones to the side.

But this power dynamic could change as temperatures warm.

Kristen Cecala of the University of the South was part of a team that studied how two salamander species adapted to warmer water in an artificial stream. They found that both of the species’ growth rates slowed. But the impacts were most dramatic on the larger salamanders. The scientists also observed a change in how the species interacted.

Cecala: “We actually saw that they started to co-occur under the same rocks, which is really unusual. In their natural environment, they don’t do that.”

She’s concerned that if this happens in real streams as the climate warms, the competition for resources could make it even harder for the larger salamanders to adapt. It’s a reminder to not just consider how climate change affects individual species. Cecala says we should also consider how rising temperatures change the ways different species interact, because those changes can compound individual risks.

Cecala: “We might actually see really rapid biodiversity declines in ways that we didn’t anticipate.”

Reporting credit: Daisy Simmons/ChavoBart Digital Media.