Fishermen from across Kauai teamed up with state employees over the Labor Day weekend to round up and remove hundreds of black-chin tilapia from Nualolo Bay on the Na Pali Coast.

The crew worked all day Saturday and into the night as well as Sunday, and managed to haul in about 300 fish. Fishermen used surround nets and throw nets under a special permit.

The fish proved to be a wily adversary, often finding ways to wriggle free from nets, according to a news release from the Department of Land and Natural Resources.

“We tried different tactics, and what seemed to work best was using throw nets at night during low tide,” said Ka‘ili Shayler, a Fish &Habitat Monitoring coordinator with the Division of Aquatic Resources.

The invasive species were first spotted in the thousands in the near-shore waters of Napali Coast State Wilderness Park last month. DLNR is trying to keep them from getting established or spreading further.

“It’s awesome for these folks to give up their Labor Day weekend with their friends and family to come to this pretty remote location to help and try to remove these fish,” said Shayler, who led the weekend operation.

Previously, fishermen had removed an estimated 1,000 of the tilapia on their own.

Officials think the tilapia were washed down irrigation canals on Kauai’s west side during rainstorms. The fish reproduce quickly and out-compete native species.

The department is encouraging anglers to keep catching black-chin tilapia. A special activities permit allows the use of small-mesh nets to remove the species all around Kauai.

“People aren’t used to eating them, but you often see frozen, farm-raised tilapia being sold in stores, so clearly, they are considered a good fish to eat,” Shayler said. “We want people to feel free to catch and use as many as they can.”