Non-native grasses may threaten Bay Area beaches


Late summer and fall are usually the best times of year to go to a beach around the Bay Area. But some are warning that the sand may not be there forever.

For all the seemingly unchanging beauty of pacific coast beaches, be advised of a process already set in motion. Those large expanses of sand we enjoy today may be gone in 50 years or so.

"Imagine sea level rise taking up the lower half, making the water higher on the beach, and plants coming down the hill, and having less beach to enjoy," UC Berkeley researcher Emily Dangremond said.

Dangremond is well on her way to becoming one of the world's leading experts on natural grasses and in this case, unnatural ones that have been taking over.

"The rest of them might be dying out and that's a huge loss of biodiversity, it's really a tragedy," Dangremond said.

Along the coast the biggest threat right now is slow creep of European beach grass.

"If this stuff keeps moving you might not have this nice beach behind me, you might just have grass and spongy ice plant," Dangremond said.

As it turns out, this is a problem of our own making in two ways. Humans brought European beach grass to our shores at the turn of the last century to protect the sand dunes. But back then, no one anticipated the future effects of climate change.

"Evolution is acting on what we've put here," Dangremond said. "It's a natural process, but we're changing the way natural processes work."

And they have been working for awhile, actually. For instance, 200 years ago, California's brush lands weren't nearly so golden. We used to have variety.

Is it pretty? Sure. But not to a biologist who sees chain reactions in coming years.

"But what about the Bay Checkerspot Butterfly that no longer has its host plant to land on and lay its eggs," Dangremond asked.

And what about larger, taller grasses burning hotter, higher and faster during brush fire season? Then more mudslides due to erosion?

"It messes up the entire ecosystem, yes," Dangremond said.

Dangermond will be keeping an eye on those developments. Ph.Ds take a long time. She has a life's work ahead, watching this process already set in motion.

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