In addition to the expansive, black sand beach that has formed at Pohoiki on Hawaii island, state officials say there are now seven new anchialine pools.
State biologists noted at least seven anchialine pools dotting the popular beach along the Puna coastline, also the site of a former boat ramp surrounded by lava during the 2018 Kilauea eruption.
Anchialine pools, according to state aquatic biologist Troy Sakihara, are landlocked, brackish water pools that are still connected underground to the ocean and groundwater. The pools fluctuate with the tides and are home to an array of endemic species found only in Hawaii.
Opaeʻula, or tiny Hawaiian red shrimp, are most commonly found in anchialine pools. The shrimp are popular in desktop aquariums and are noted for their ability to evolve and thrive in a variety of habitats like volcanic rock and sand.
While biologists say they are not surprised that opaeʻula and other native shrimp are beginning to show up at Pohoiki, where and how they got there still remains a mystery.
State officials, however, are reminding the public to respect the new life thriving in the pools by not snorkeling or swimming in them, and minimizing interactions with them.
One woman was recently spotted floating in one of the anchialine pools, with a snorkel, for more than an hour.
“We want to educate folks and ask them not to disturb these pools and minimize their interactions with them,” said Hawaii Division of Aquatic Resources administrator Brian Neilson in a news release. “Please don’t swim or snorkel in them, as you may be killing some of the most endangered aquatic creatures in the state. Respect them and enjoy them, with your eyes, only.”
The pools are valuable resources, ecologically, biologically and culturally, according to Neilson.
“Our team is currently working on a rules package to provide better management strategies for anchialine pools,” he said. “One of the things people can do right now is to stay out of these sensitive areas. Sunscreens and other body oils can degrade water quality and potentially kill creatures like the opaeula.”
Anchialine pools are historically a critical sources of fresh water, particularly in arid regions, officials said. Hawaii is home to an estimated 600 anchialine pools.