San Francisco's Presidio springing to life after this year's series of storms

SAN FRANCISCO (KGO) -- Wildlife ecologist Jonathan Young is measuring the effects of our recent storms, which he says have brought the San Francisco Presidio's often secluded watersheds roaring back to life. In the case of this marsh near Crissy Field, they've flushed in a mix of fresh water and salt water that's still able to support the oysters and other coastal creatures that call the area home.

"And testing the salinity just now, it was at about 27% around the depth they're at. So it's pretty good considering the amount of freshwater that came into the system with that storm," says Young.

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But to appreciate the true scale of the storm's impact, you have to trek deep into the Presidio hills. That's where secluded seeps and springs like El Polin are flowing with Sierra-like runoff. The water feeds a meandering system of wetlands, some of them seasonal, which in turn support an astounding variety of wildlife.

"And during droughts, you don't get that much rain. So those seasonal wetlands rarely fill up or when they do fill up, it's a sad little amount of water not enough for a lot of the wildlife that depend on it," he says.

But this year's storms have delivered runoff, and much more. Tucked in the dunes on the south side of the Presidio sits a newly-created pond, expected to last for much of the year. Young says it's likely to be a critical habitat for the Chorus Frog, a species that was nearly extinct in the city, until it was reintroduced in the Presidio.

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"So the first warm night we get, there's going to be a lot of egg masses laid, which could be any day really. So to the frog stay in this area when they hatch, so they'll hatch, they'll turn into tadpoles, which are gill breathers, which require water freshwater. And then over the course of several weeks, they're starting to develop, and they'll eventually turn into froglets," Young explains.

And the availability of water will eventually reverberate across a complex ecosystem, from insects to the coyotes that live and breed in the park. While some of the habitats are remote, others are already on display for visitors strolling the wetlands in areas like Crissy Field.

"Yeah, a lot of a lot of migratory waterfowl are going to be dependent on these freshwater wetlands," Young said. "As they migrate from north to south along the Pacific Flyway. They need places to rest and recharge and eat food. So they find these wetlands where a lot of the aquatic vegetation is going to be growing which is their food."

And for the time being, flowing with water.