CRAIG T. KOJIMA / CKOJIMA@STARBULLETIN.COM
At a demonstration of the Super Sucker boat in Kaneohe Bay yesterday, diver Eric Conklin, with a hose, prepared to vacuum algae from the coral beds. A boat above will have the algae gushing out onto a collection table for disposal.
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Super Sucker slurps alien algae
A group effort leads to a device to remove invasive algae from Kaneohe Bay
It looks like a contraption that treasure hunter Mel Fisher used to salvage sunken cargo from the fabled Spanish galleon Atocha.
But instead of scooping up gold coins and jewels from the ocean floor, the 13-foot-by-25-foot barge dubbed Super Sucker is removing a particular type of alien invasive algae killing the coral reef in Kaneohe Bay.
The pump, which transports ocean water and algae from the bay to the barge's deck, was adapted from use in gold mining, said Brian Parscal, University of Hawaii operations supervisor for the project.
The water and algae do not pass through any blades, so any marine life like crabs or sea cucumbers that get caught in the suction tubes can be returned to the bay.
"Though they went for the ride of their life, they are unharmed," Parscal said.
The pump also keeps the algae intact because the plant can regenerate from broken fragments.
Parscal said the pump can remove 800 pounds of algae per hour, equal to the effort of 150 volunteers and 10 divers.
The algae's scientific name is Gracilaria salicornia, but it's commonly known as gorilla ogo. It is one of five alien algae of concern in Hawaiian waters and one of two found in Kaneohe Bay. It's not the most pervasive of the alien species, but was targeted because of its destructiveness, said Eric Co, marine resource manager for The Nature Conservancy.
CRAIG T. KOJIMA / CKOJIMA@STARBULLETIN.COM
Nadiera Sukhraj, left, and Jamie Marzhetti picked out crabs, sea cucumbers and worms for return to the bay yesterday.
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The algae grow on coral, blocking its access to sunlight and pressing down on it with its weight, said Cynthia Hunter, UH Manoa Biology Program assistant professor. They also clog holes where juvenile fish live, reducing their habitat and survivability, she said. And they spread quickly.
Gracilaria salicornia was introduced in waters off Coconut Island and the Waikiki War Memorial Natatorium in the 1970s by a UH biology professor in a failed attempt to start an aquaculture industry in Hawaii. It has since spread to other parts of Oahu and Molokai.
It belongs to the same family of algae as the native short ogo and long ogo, another introduced species. It too is edible and is an ingredient in some poke recipes.
"If you're going to use it, great. But don't spread it. There's more than enough of it around," Co said.
Native sea urchins also eat the algae but researchers are still trying to figure out how to get them to reproduce more quickly.
Taro farmers Paul and Charlie Reppun has been using the collected algae for compost.
The Super Sucker project is a partnership of The Nature Conservancy, which secured much of the funding; the University of Hawaii, which is doing the research; and the state Department of Land and Natural Resources, whose Aquatic Resources Division operates and manages the barge.
The Hawaii Institute of Marine Biology houses the barge at its Coconut Island facility.
After 12 months of prototype testing and refining, the partnership unveiled Super Sucker to the public yesterday. The project is still in its research stage. However, the state has funding for a Super Sucker Jr., which can be deployed in shallower, near-shore waters outside the bay.