Kelp Forest Restoration
Seatrees has partnered with Seals Watersports and the grassroots volunteer group P.U.R.P. (Purple Urchin Removal Project) to restore the kelp forests of Stillwater Cove, located along the scenic Northern California coastline. Once teeming with underwater life, this cove has suffered from the overpopulation of purple sea urchins - voracious grazers that have wiped out vast areas of kelp, leaving the local ecosystem on the brink.
This community-led effort is powered by a network of divers, freedivers, and ocean lovers who remove invasive urchins by hand - without funding or formal scientific support. Now, with help from Seatrees, this restoration movement is scaling up .
How Seatrees is Funding This Work
Through donor support, Seatrees is funding the air fills required for volunteer scuba divers to carry out this challenging underwater work. We’re also helping outfit them with the gear they need, from game bags to lift bags and even underwater gardening tools, to safely and efficiently remove the destructive urchins.
Seatrees’ funding will support:
- 500 air fills to support the divers
- Equipment like dive bags, lift bags, bolt snaps, rakes, and collection bins
- Maintenance and cleaning support for all gear
Project Summary
- Goal: Remove purple sea urchins to allow kelp forests to regrow
- Method: Volunteer-led urcWatersports dives (freedive and scuba)
- Support from Seatrees: Funding for 500 scuba tank air fills + dive equipment
- Impact Area: Stillwater Cove, Sonoma County
- Community Partners: Seals Watersports and P.U.R.P.
Impacts + Outcomes
By removing purple sea urchins, this project makes way for the natural reestablishment of native kelp species.
Over time, this effort will:
- Restore critical habitat for fish, crabs, sea stars, and marine mammals
- Support biodiversity hotspots unique to Northern California
- Reduce urchin barrens and increase kelp canopy coverage
- Re-engage local communities with hands-on ocean stewardship
Volunteers track the weights of urchins removed, dive data, and visible ecosystem recovery, which is shared through informal reports and observations.
Project Updates
- 33,945 lbs of purple urchins removed since Sept 2023.
- Kelp returning with 7+ kelp and sea lettuce species observed.
- Marine life rebounding: abalone, anemones, snails, octopi, perch, lingcod, cabezon, monkeyface eels.
- Marker buoy system ensures thorough 10’ radius clearing zones.
- Juvenile urchins targeted to prevent future overgrazing.
- Goal: reduce to ~2 urchins/m² (NOAA guidelines).
- 3 more years of clearing projected for Stillwater Cove.
Project Partners
P.U.R.P. (Purple Urchin Removal Project) was founded by Eric Sedletzky as a grassroots movement of divers committed to reviving kelp forests by physically removing sea urchins. With no formal funding, this group grew through passion, dive shop flyers, and text alerts, mobilizing dozens of volunteers month after month.
Seals Watersports, run by Zeke Cissell, amplifies the effort by coordinating dive trips and logistics, advertising events through their channels, and providing the infrastructure to bring this vision to life.
Together, this partnership is creating a scalable model for community-led kelp restoration, powered by oxygen, grit, and love for the ocean.
Sustainable Development Goals
- 3,945 lbs of purple urchins removed since Sept 2023.
- 18,932 lbs removed with SeaTrees-supported air fills since Sept 2024.
- Biodiversity recovery observed: 7+ kelp species, plus return of abalone, anemones, snails, octopi, and multiple fish species.
- 3+ years projected clearing timeline to restore balance in Stillwater Cove.
Climate Action
