KAILUA-KONA — Two years into a 10-year rest period at the Kaupulehu Marine Reserve on the North Kona coast of Hawaii Island, fish populations are starting to bounce back, according to a release issued by the Nature Conservancy (TNC) Wednesday.
TNC dive surveys indicate some species have jumped nearly 60 percent.
“We’ve been hearing from longtime fishermen that the area is starting to remind them of old Hawaii,” said Leina‘ala Lightner, a lineal descendant of Kaupulehu and curator of the Kaupulehu Interpretive Center at Kalaemano. “Divers who came to our invasive fish removal event last summer said they were seeing big schools of weke, pualu, uhu and manini, as well as healthy coral, limu, opihi and wana.”
Chad Wiggins, Hawaii Island marine program director for TNC, said 2018 surveys confirmed anecdotal evidence from within the community.
“On more than 183 dives over 7 miles of coastal reefs, we observed more fish — fish we hadn’t seen in the area before — and bigger fish,” Wiggins said. “While it is too early to determine the long-term effects of the rest area, these signs of recovery show promise for the community’s goal of supporting a sustainable subsistence fishery in the region.”
Baseline surveys conducted from 2009-16, before the rest area began, demonstrated no difference in reef fish communities inside and outside the rest area, the release stated.
But an analysis of TNC’s September 2018 monitoring data shows that populations of some resource fish, including prized species of wrasses, parrotfish and surgeonfish, are increasing. Those increases, the release said, are higher inside the rest area than in adjacent areas. Data showed the following:
• 62 percent increase in some wrasses (i.e., hogfish) inside the rest area, and 3 percent outside
• 30 percent increase in some parrotfish (i.e., uhu) inside the rest area, and 3 percent outside
• 46 percent increase in some surgeonfish (i.e., kole) inside the rest area, and 21 percent outside
• Evidence of spillover, or fish populations increasing, just outside the reserve boundary
In addition, coral surveys documented stable or slightly increasing coral cover following the mass bleaching event in 2015-16 that saw high ocean temperatures kill an average of 50 percent of the coral in West Hawaii. The release asserted this serves as an additional indicator that reducing impact on an area can help promote reef resilience.
The initiative to rest the reefs of Kaupulehu was dubbed “Try Wait” and led by the Kaupulehu Marine Life Advisory Committee.
In 2009, the committee brought in scientists from TNC to conduct coral reef and fish surveys at Kaupulehu and neighboring Kukio. TNC’s scientific monitoring documented the decreases in important food fish that community members were observing, the release said.
The community led a rule-making process to rest the reef for 10 years to replenish depleted fish stocks to levels that could support sustainable harvest. After numerous public meetings, the Department of Land and Natural Resources created the Kaupulehu Marine Reserve in July 2016.