Invasive Alien Algae Removals

Volunteers remove alien algae from the bay and

put them into bags for recycling or disposal.

Removing alien algae from high priority coral reefs is essential to the survival of Hawaii’s reefs. Since early 2007, we have removed, by hand, approximately 18,000 lbs. of alien algae from Maunalua Bay with the help of hundreds of volunteers from students to retirees across the island.

With the new “mini Super Sucker” based at Maunalua Bay, we have begun to remove alien algae by mechanical means. The original Super Sucker is basically a modified gold dredger that sucks up alien algae from the reefs. It can remove 800 pounds of alien algae in an hour, equivalent to the efforts by 150 volunteers and 10 divers. The smaller, mini version is more portable and can be deployed in areas that are more remote, where manual removal efforts would be impractical or impossible.

Volunteers prepare the Mini Sucker for action.

The “Mini Sucker,” is a unit that is ideal for shallow, near shore areas, where a small group of volunteers can collect large amounts of alien algae from more area than is possible from manual removal efforts in the same amount of time. Alien algae are collected from an intake hose that brings it through the vacuum compartment of the pump, and expels it directly into a porous bag.

We were the first to test this approach on Avrainvillea amadelpha, a particularly problematic alien algae species that embeds itself in soft substrates such as sand in very shallow water. It is much more difficult to remove than other invasive algae. Our application of this machine is still in the development phase, but as our proficiency with the mini-sucker improves, it may prove to be the most efficient way to remove alien algae populations in shallow water to date.

Please check out the Activities & Events Calendar for dates and contact info for 2009 invasive algae pulls.

Here is a short video from a recent alien algae clean up at Maunalua Bay involving dozens of volunteers. Video shot and produced by Catherine Toth.