Kappaphycus spp. / Eucheuma sp.) by the SuperSucker sign at HIMB. Thanks to the SuperSucker folks for providing the sample.
Back in the 1970's, two types of Kappaphycus were introduced into Kane'ohe Bay as well as a very similar looking Eucheuma sp. All are very useful elsewhere in the world where they are cultivated for carageenan and other algal products used in foods and cosmetics. They are not wonderful here in Hawaii where they overgrow the reef and corals (hence the common reference to them as "smothering seaweeds").
Groups can now get a better view of these seaweeds. They are different than the gorilla ogo that we more commonly see around the island and even more massive if given a chance to grow. These are the target species for the Supersucker project. Kappaphycus has not spread through the Hawaiian Islands yet, unlike the gorilla ogo - so it would be nice to get it under control.
For a short blog post on the urchin project, see John Platt's Scientific American blog post, Sea urchins bred to eat invasive seaweed in Hawaii or check last weeks blog post below.