It’s Saturday afternoon and the Birch Aquarium is swimming with families. There are a lot of kids in the “Hold Fast” exhibit about kelp forests. They’re running through a display of 27 kelp plant images, printed on silk sheets that hang from the ceiling to the floor.
“What should I say about this area? Do we like this area?” said Andrew Corman, a San Diego dad and high school teacher as he questioned his two kids.
Lots of kids are darting through and around the sheets, wrapping themselves in them or lounging on colorful padded ottoman chairs.
Corman called it a great exhibit.
“It emulates what the kelp is. It kind of shows exactly how they flow with the water. They’ve got areas where they can sit and relax just like aquatic animals would in the kelp forest,” he said.
“It’s been wonderful to sit and watch kids explore this area,” said Oriana Poindexter, a photographic artist and marine scientist who created the silk kelp forest where the kids frolic.
“They know exactly what to do. They dive right in! They run straight for the center and enjoy interacting with the silk. Touching them. Looking up,” she said.
Poindexter also co-curated the exhibit, “Hold Fast: We can all find something to hold on to.” Hold fast is a reference to that part of a kelp plant that anchors the plant by grabbing rocks at the sea bottom as the plant grows and reaches for the surface and the sunlight.
Poindexter often dives in the forests off the San Diego coast, and she’s seen some of the devastation that marine heat waves have done to local kelp.
"Hold Fast" co-curator Megan Dickerson is director of exhibits at Birth Aquarium. She said the exhibit has some of that sadness but also showcases the natural beauty and the art it inspires. She says that gives her hope.
“I think maybe I can do a beautiful thing. And those beautiful things add up to something that’s beyond hope and it becomes reality. We’re writing ourselves a new future,” Dickerson said.
Poindexter’s kelp prints, hanging from the ceiling or mounted on the walls, are done with cyanotyping.
It’s a chemical process that predated photography. The plants are placed on paper that's coated with iron salts and left in the sun until they leave a realistic, life-sized print. Another featured artist, Dwight Hwang, does a similar art called gyotaku, where he coats sea creatures in soot-based ink and presses them onto paper.
“So when Oriana prints a segment of kelp that she’s harvested or when Dwight Hwang prints an animal that has washed up on shore, they are creating a one-to-one print of that thing. And conceptually this exhibit is about remembering things that we don’t see,” Dickerson said.
A kelp forest is a habitat and a nursery, said Mohammad Sedarat. He’s a Ph.D. student at Scripps Institution of Oceanography who studies kelp. His work is also featured in "Hold Fast."
Sedarat said marine heat waves, and slowly rising sea temperatures, have had a very negative effect on local kelp forests in just the last 10 years, reducing the footprint of local kelp forests dramatically.
He said heat waves are getting more common and San Diego’s kelp forests have not been recovering like they should.
“Like what we had in 2013 through 2016: We had crazy El Nino warm waters. Temperatures spiked,” Sedarat said. “We lost kelp and that’s when that huge signal of abundant kelp in 2013 disappeared. So we’ve had some small recoveries since then but it just can’t stick on.”
Sedarat said summer water temperatures of 80 degrees or higher are a kind of red line that most varieties of giant kelp can’t survive in. In the lab, he is trying to identify natural kelp or hybrids that can tolerate warmer temperatures, and that may be the future of local kelp forests.
We can hope that a genetically diverse kelp forest will favor those plants that are heat tolerant, and they will take over. But when it comes to planting hardier varieties in the wild, Sedarat said marine scientists don’t wanna go there. Not yet.
“Artificial selection is the bigger topic right now. We’re not ready to put out kelp that’s been naturally selected or even modified yet. It’s still about preserving the status quo,” he said.
The status quo is still out there, though less than it was. Poindexter talks about diving in the local kelp and seeing the amazing way it catches the sunlight. And yes, it is home to lots of fish.
“Some of my favorite creatures to see are the tope sharks, that cruise through there. The sevengill sharks. There are the sheepshead that are obnoxious. They really get up in your face when your free diving — they don’t seem to have a lot of fear,” she said.
"Hold Fast" will be on display at the Birch Aquarium until September 2024.
