Walk around the edge of Keawanui Fishpond on Molokai’s east end, and you’re likely to catch a glimpse of pualu, a hardy grazing yellow sturgeon fish that swims in thriving schools throughout the 50-acre pond. But notably absent are reef fish like ‘ama’ama (mullet) or o’io (bonefish), “the silvers” that are more popular on the average dinner plate.

“You can go around the pond all day and not see one,” said Hanohano Naehu, the kia’i loko, or fishpond guardian of Keawanui. “So get fish — just not the fish of choice.”

That’s why Naehu is looking forward to an incoming delivery of Hawaiian striped mullet from the hatchery of Hawaii Pacific University’s Oceanic Institute. The mullet are being placed in three fishponds around the islands — Keawanui, He’eia fishpond on Oahu and Haleolono fishpond on Hawaii island — as part of a study to learn how different factors in each fishpond impact the growth rate and health of fish, according to a report by the National Oceanic and Atmospheric Administration’s Pacific Island Regional Office.

“This mullet is almost like one investment for our place and our kids in the future,” Naehu said Wednesday. “This is the opportunity for us, for our generation to take the bite and not eat these fish, so we can actually bring them back and they can be here for our grandchildren.”

It’s the second attempt at the study, Naehu said. There were differences of priorities in the first round — researchers “were doing a business project, and we were doing a stocking enhancement project,” Naehu said — as well as differences in logistics. The study wasn’t customized to each fishpond, and while it worked on paper, it flopped in practice, Naehu said. The fish were placed in pens away from the freshwater springs that Naehu calls “the mama’s milk to the first stage of life.”

“So long story short, the first run was one crash,” Naehu said. “So we using this next run coming up. They are allowing us to customize. . . . The lesson learned is if you going into somebody’s house, ask them what do you think is the best way to do this.”

Naehu said that, this time around, he plans to place three pens in a line from the shore to the middle of the pond and finally out to the far wall. The mullet will move from pen to pen as they grow. Afterwards, they’ll be released into the full pond, not taken to markets or restaurants. Naehu said he’ll be taking notes on what happens to the fish from introduction until release. This time, they’ll be placed next to the freshwater springs.

“The whole analogy is you taking young children from the city and throwing them out in the country and saying ‘good luck,’ ” Naehu said. “That’s rough. There’s a way to make it more comfortable, the transition. . . . You put them close to mama’s milk. You introduce them to mama; they going acclimate quick.”

If the fish thrive, that could be a big boost to the pond, which is located near Wavecrest Resort and Kilohana Elementary School on the island’s east end. Naehu said the fishpond “is a reflection of your ahupua’a,” and the supply of fish is impacted not only by the fishing practices around the island but also the landscape in the mountains above, prone to erosion because of cattle and dotted with non-native plants like kiawe or lantana.

“That’s been the problem,” Naehu said. “We not growing fish. We supposed to be growing limu. But you no more any nutrients coming from the land to feed the ocean plants. You get one desert now, which used to be a forest.”

Fishponds were once abundant along Molokai’s south shore, which boasts an extensive fringing reef. The island once had more than 60 fishponds encompassing more than 1,500 acres, according to a fishpond restoration manual by the University of Hawaii’s College of Tropical Agriculture and Human Resources. Fish were either caught and brought into the pond or swam through the makaha, or sluice gates, that allowed smaller, juvenile fish to enter but trapped larger fish.

“We had the ability to create more food than we needed,” Naehu said. “That’s this place. The machine is still here. And we didn’t stop doing it because it stopped working. We stopped doing it because we got occupied. We got taken over.”

Naehu and longtime friend Kalaniua Ritte have been working on restoring Keawanui since 2000. They had the fishpond walls up and functioning by 2004. The pond was doing well until 2011, when a magnitude-9 earthquake shook Japan and caused a tsunami that eventually flattened nearly the entire wall at Keawanui. It took four people one year and four months to restore the 2,000 feet of wall, Naehu said. All of the fish at Keawanui are herbivorous, limu-eating species.

Naehu said there’s “no way of getting one good estimate” of how many are in the pond; it depends on the species and where you look.

Protection and restoration of the local fish population is a long and ongoing process islandwide. Just outside of Kaunakakai town, the nonprofit Ka Honua Momona also has been working to restore two other fishponds — Ali’i and Kaloko’eli, both about 30 acres each. And, on the island’s north shore, community members led by Mac Poepoe have been working to establish a community-based subsistence fishing area designation that would set catch restrictions on threatened species.

Naehu said he’s not sure how much fish Keawanui will receive and when. According to NOAA, the fishponds should be getting the mullet after the breeding season begins this winter. In the first round of the study, Keawanui received fish in groups of 4,000, 8,000 and 16,000.

“We getting to the point where all the people that want to save the planet — the natives, the scientists — we all got to help each other,” Naehu said.

* Colleen Uechi can be reached at cuechi@mauinews.com.