Alien algae invasions have been identified as a current and significant threat to
our nearshore reefs in Hawaii. Invasive algae smothers coral and the surrounding reef
thereby reducing the diversity in the reef community. According to a recent economic
report, invasive algae in Kihei, Maui cost the state $20 million annually. However,
invasive algae are not isolated to Kihei, Maui. There are significant impacts in other
areas including Waikiki, Oahu; Kaneohe Bay, Oahu; and south Molokai. Statewide, the
economic impact of invasive algae is much greater than $20 million annually.
Research is needed to understand the complex interactions between algae and the
fish that feed on them which affect our coastal communities. Nineteen species of
potentially reef changing algae have been introduced to Oahu since 1950 with at least
four of these species dominating shoreline areas. Some of these non-native species appear
to have spread throughout all of the main Hawaiian Islands, while others are only found
on Oahu or create significant problems such as the large blooms of the alien red alga
Hypnea musciformis on west Maui.
Currently, there are four efforts and areas of research to manage the alien algae
situation. These efforts include: 1) a volunteer-based algae removal effort called "Aohe
Limue - No Alien Algae" that periodically removes algae from Waikiki, 2) the
development and deployment of a mechanical suction system capable of removing large
volumes of algae is being investigated, 3) research on biological control using native
grazers to control or eliminate invasive algae, and 4) the feasibility of repopulation of
native algal species.
