Invasive species are a reoccurring theme throughout Hawai’i from land to sea. While some are worse than others, they all pose a threat to the unique and native ecosystem of our island state. One of the most threatening invasive species to our coral reef ecosystem is Gracilaria salicornia, or gorilla ogo. Found in tide pools and on reef flats, gorilla ogo forms thick mats, smothering and carpeting any life reef structure much unlike its deliciously edible native counterparts, G. parvispora and G. coronopifolia, (ogo and limu manauea.) The invasive gorilla ogo reproduces both sexually and asexually by fragmentation; any small piece of algae can break off, float away and establish a new population. The algae was introduced to both Kāneʻohe Bay and Waikīkī in the 1970s but has since spread to Hawaiʻi Island and Molokaʻi.
What a nightmare!
Last week, Brad and Kirsten hopped on over to Molokaʻi with folks from the Division of Aquatic Resources (DAR) Aquatic Invasive Species team and the Office of Hawaiian Affairs to help Molokaʻi’s community survey the gorilla ogo distribution along their southern coast. The community has expressed concern about the gorilla ogo distribution as it is inhibiting their fishpond production and hurting their fishing efforts; much of the island’s population subsists off the land and their environment is one of their most prized attributes.
DAR, OHA, and TNC helped to teach 40+ community members over three days how to use GPS, measure sediment depth, and identify invasive and native algae. Together, we covered over 14 miles of shoreline and mapped thousands of GPS points. The Molokaʻi community can now independently continue their efforts to map the remaining miles of the south shore and will be working with DAR and TNC in the future to develop and management plan for the gorilla ogo population.