Department of Land and Natural Resources

JOSH GREEN, M.D. GOVERNOR

DAWN CHANG CHAIRPERSON

For Immediate Release:  February 16, 2023

MAJOR MILESTONE REACHED TO COMBAT INVASIVE ALGAE IN KĀNEʻOHE BAY

1,000,000 Native Sea Urchins Raised and Outplanted

To view video please click on photo or view at this link: https://vimeo.com/799337621

(KĀNEʻOHE BAY, OʻAHU) – A major milestone was reached this week as teams from the Ānuenue Fisheries Research Center (AFRC), a facility of the DLNR’s Division of Aquatic Resources (DAR), planted the one millionth juvenile native sea urchin in Kāneʻohe Bay on Oʻahu. Since January 2011, AFRC has successfully spawned and raised collector urchins in captivity with the purpose of releasing them in the bay as part of an ecosystem-based management plan for environmental mitigation work in the bay and off Waikīkī.

“The millionth urchin and about 13,000 others were planted on a patch reef in North Kāneʻohe Bay where they will go to work, grazing on invasive seaweed,” Eric Dilley, DAR Monitoring Coordinator said.

The native urchins act as underwater gardeners and help keep invasive seaweeds under control. This allows corals to grow and provide habitat for reef fish and other marine life.

Urchins are spawned, settled, and raised at AFRC on Sand Island as part of a multi-agency effort, involving DAR, Pacific Cooperative Studies Unit (PCSU), NOAA, the U.S. Fish and Wildlife Service and the Hawai‘i Department of Transportation (DOT). The sea urchin hatchery is a 24/7 operation that raises sea urchins until their juvenile life stage. It takes approximately four-to-six months until urchins are large enough to be transferred to Kāneʻohe Bay.

Before the urchin hatchery was created, invasive macroalgae grew in thick mats on top of reefs in the bay, effectively smothering them, blocking sunlight, and killing coral. Since these native collector urchins have been outplanted, invasive seaweed cover has been reduced and coral health has improved. Today, these areas are monitored for algae regrowth and urchins are placed as needed.

In memory of a long-time DLNR employee, staff named the millionth urchin “Vince”, in honor of Vincent Goo, a fisheries technician at AFRC who passed away in 2021.

“Vince was one of the unsung heroes of the urchin hatchery,” said hatchery manager David Cohen. “He took an interest from the very beginning and helped me and the project every step of the way.”

Next month, crews will begin their intensive field season, which includes monitoring 22 patch reefs in Kāneʻohe Bay for coral health and the presence of invasive algae.

 

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RESOURCES

(All images/video courtesy: DLNR)

HD Video – 1,000,000 Sea Urchins, Kaneohe Bay (Feb. 15, 2023): https://vimeo.com/799337621

(SOTs – Eric Dilley, Monitoring Coordinator, DLNR Division of Aquatic Resources)

 

Photographs – Kaneohe Bay 1,000,000th Sea Urchin Outplantin (Feb. 15, 2023): https://www.dropbox.com/sh/c8w351guhpjge04/AADMJ7M0-OsiTTtNCXs5LY3ya?dl=0

 

 

Media Contact:

Madison Rice

Communications Specialist

[email protected]