Santa Cruz vs. Ice Plant

Invasive species threat to biodiversity

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Ice plant encroaching Natural Bridges State Beach. Photos by Danielle Del Rosario.

West Cliff, one of the most scenic locations in Santa Cruz, is a hot spot for tourists and locals. Each turn on the winding road displays another scenic beach. The yellow and pink flowers of the ice plant stand out against the green landscapes. The plant adds to the beauty of West Cliff, but it’s impact on the ecosystem isn’t as pretty. 

Ice plant is an invasive species that overpowers native flora on the bluffs near Natural  Bridges.

“Like many invasive and exotic plants that come from one area to another area, ice plant tends to form monocultural ecosystems,” said Bill Henry, director of Groundswell Coastal Ecology. “When it takes over, it essentially smothers surrounding flora. […] You lose almost all  biodiversity.”

Photo by Danielle Del Rosario.

Ice plant disrupts the breeding of the Brandt’s cormorants, a native seabird species. Brandt’s cormorants require a desolate location to breed, away from human interference. In Santa Cruz, the optimal location for breeding is on the edges of the bluffs near Natural Bridges. However, ice plant has overpowered these bluffs, preventing the cormorants from building  nests.

With the degrading number of Brandt’s cormorants nests and offspring, as well as other floral and faunal communities, local ecologist Henry decided to take matters into his own hands.

Henry, accompanied by ecologists Josh Adams, Ryan Carle and Jessie Beck, sought to remove ice plant encroaching on the ledges by Natural Bridges to restore native species and aid the breeding habits of the Brandt’s cormorants. In April 2011, the ecologists bearing only a lopper and climbing ropes, removed a portion of ice plant from a cliff where very few Brandt’s cormorant nests laid. The following day, Henry and his team went to observe the newly restored cliff.

“The next day we came back and the amount of nests had grown by six-fold,” Henry said. 

It was clear the removal of ice plant benefited the preexisting ecosystems. Throughout the breeding season in 2011, 16 nests and 32 chicks were documented.

Since the success in 2011, Henry and others formed Groundswell Coastal Ecology, a group dedicated to building live shorelines using nature-based solutions. The project at Natural Bridges is ongoing, and has inspired Groundswell Coastal Ecology to tackle other restoration projects.

“We now have eight different projects, as far down as the Rio del Mar Esplanade,” said Henry. “We have restored about a half mile of coast in Seabright, between the river mouth and the harbor mouth. We have a project at Steamer Lane. […] We have another project at Davenport Landing. We have two small demonstration plots that are on West Cliff, and two butterfly restoration  projects.”

In 2018, 36 Brandt’s cormorant nests were documented, increasing by 20 since 2011. Also in 2018, 84 chicks were documented, increasing by 52 since  2011. 

“I have a background in ecology, and I know the value of diversity from an ecological perspective. But truly, my inspiration roots from when I had kids,” said Henry. “After having kids, I would take them down to West Cliff and look at the monoculture present on the cliffs thinking ‘it would be great to help the biodiversity ante.’ The main thing was wanting something different for my children, and to improve the place that I love.”