California officials are raising concerns about elevated wildfire risk across the San Joaquin River watershed this year, as warm temperatures, dry fuels, and reduced snowpack set the stage for another challenging fire season.

These conditions can increase the likelihood of larger, more intense fires in the Sierra Nevada headwaters that feed our river system.

At first glance, that sounds like bad news for fish and freshwater life.

But the science tells a more nuanced story.

A recent peer-reviewed study from Oregon State University found that following megafires, fish often thrive and amphibians prove resilient. The researchers looked at streams impacted by severe wildfires and found that fish populations often held steady or even increased after fire.

Why?

When fires reduce forest canopy, more sunlight reaches streams. That added light boosts algae and aquatic insect production—the base of the food web. In turn, this creates more food for fish.

Researchers found that in some burned watersheds, total fish and trout densities were actually higher, and young fish grew faster in slightly warmer water.

Even more encouraging, amphibians and crayfish—key parts of the ecosystem—largely persisted regardless of burn severity.

This doesn’t mean fire has no risks. Severe burns can still trigger erosion, sediment flows, and temperature spikes—especially if followed by storms. But it does remind us that wildfire is not just destruction. It’s also part of how natural systems reset and renew.

Here in the San Joaquin River watershed, the biggest impact is actually what happens after the fire. Adequate river flows, cold water releases, and healthy floodplain connections can determine whether fish populations struggle or thrive.

Fire alone doesn’t define the future of our river.

How we manage water and habitat afterward does.

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