Marine Aquatic Invasive Species (AIS) in Hawaiʻi
Animals have been introduced throughout the world by humans, either accidentally or intentionally. When in a new environment, introduced animals can compete with native ones for food or space; introduce new pests, parasites, or pathogens; and generally cause a disruption to the native environment. When these introduced species cause harm, they are regarded as invasive. text source (Contribution No. 2001-005 to the Hawai’i Biological Survey)
Like on land, Hawai`i’s marine ecosystems face the threat of invasive species– known as aquatic invasive species (AIS). It is the responsibility of the Bernice Pauahi Bishop Museum Hawaii Biological Survey to collect, compile, and make accessible information about past and present species introductions–both benign and invasive– to aid in future AIS detection and management.
Like on land, Hawaiʻi’s marine ecosystems face the threat of invasive species – known as aquatic invasive species (AIS). It is the responsibility of the Bernice Pauahi Bishop Museum Hawaii Biological Survey to collect, compile, and make accessible information about past and present species introductions – both benign and invasive – to aid in future AIS detection and management.
Marine AIS in Hawaiʻi
While AIS encompass all invasive aquatic species including freshwater, marine AIS are of particular concern in Hawaiʻi. There are many ways new marine species are introduced, some unintentional, others intentional. If the environmental conditions are favorable, an introduced species that has established itself may become invasive, outcompeting the local native fauna and devastating marine habitats. The best way we can protect our native marine fauna in Hawaiʻi is to reduce the amount of introduced species coming to Hawaiian waters and to control/eradicate those that become highly invasive as quickly as possible.
Marine Invertebrates: Probable Mechanisms of Transport to the Hawaiian Islands
Mechanism | Species | % Established |
|---|---|---|
Hull fouling | 212 | 90 |
Solid ballast
| 21 | 90 |
Ballast water | 18 | 89 |
Intentional release: Fishery | 18 | 28 |
Parasites on nonindigenous species
| 8 | 88 |
With commercial oysters: unintentional | 7 | 100 |
Aquarium release | 3 | 67 |
Biogeography of Marine Nonindigenous Species in the Hawaiian Islands
Origin | % | Origin | % |
|---|---|---|---|
Indo-Pacific, Philippines | 212 | Southern Hemisphere | 2.8 |
Unknown
| 21 | Australia and New Zealand | 2.4 |
Unknown, worldwide
| 18 | Tropical eastern Pacific | 2.4 |
Tropical western Atlantic (Caribbean)
| 18 | Oceania | 2.1 |
Japan-Asia
| 8 | Other | 2.3 |
NW Atlantic (Europe and MEditerranean) | 7 | ||
West Coast North America | 3 |
Hawaiʻi has a long history of marine introductions due to our geographic isolation and rich history of marine vessel traffic. Ships provide the largest vector for marine introductions in Hawaiʻi, transporting species that have attached themselves to the surface of hulls (hull fouling) as well as those living within or amongst the ballast inside. The majority of these species are native to the Indo-Pacific Philippine Islands region. Not all introduced species in Hawaiʻi become established, but the majority of them do.
Marine bioinvasions of Hawaiʻi
The article provides an overview of the nonindigenous marine and estuarine species in the Hawaiian Archipelago. It details the efforts to catalog these species through literature, museum specimens, and field collections. The paper also observes historical trends in species introductions, linking them to human activities and scientific efforts across different decades. Click here to read it directly.
Marine AIS In Hawaiʻi
History of Marine Introductions in Hawaiʻi
HBS: Ecological Recordkeepers
Records and resources
Through the Hawaii Biological Survey at Bishop Museum, a count of the total number of species in the Archipelago has been compiled. As of 2020, of the estimated 4,100 known marine and brackish water invertebrate fauna from the Hawaiian Islands, approximately 300, or 7%, were classified as nonindigenous. Arthropods have been the most prolific, but there are a significant number of alien species from understudied animal groups including sponges, polychaetes, bryozoans, and tunicates. Due to the large number of nonindigenous marine invertebrates in Hawaiʻi and the limited amount of information known for most of them, there is still much to learn about them and their impacts.
Introduced Marine Species in Hawaiʻi (by phyla)
Current Project: Pearl Harbor AIS
An unidentified xeniid octocoral was first detected in Pearl Harbor during benthic surveys in 2020. In 2022, coordination between several organizations and government agencies, including Bishop Museum, led to the confirmation of the coral as Unomia stolonifera as well as the detection and identification of an additional octocoral species found growing in an adjacent patch as Capnella cf. spicata. Both have spread rapidly and, while they currently remain confined to the harbor, threaten the integrity of our reef habitat.
More surveys of Pearl Harbor since the initial discoveries have led to the finding of several other introduced species. All of them are popular aquarium species suggesting that introduction was likely via aquarium dumping.
Unomia stolonifera
Common names: Pulse coral, pulsing Xenia
The swaying and gently pulsing movements of this soft coral makes it a popular aquarium species. U. stolonifera is capable of rapid proliferation through both fragmentation and sexual reproduction.
[WORMS link]
Capnella cf. spicata
Common name: Kenya tree coral
Capnella cf. spicata is a popular saltwater aquarium species. True to their name, this soft coral is tree-like with a stout base that branches at the top with polyps. They can reproduce sexually or by budding and fragmentation.
[WORMS link]
Anemonia manjano
Common names: Manjano anemone
Anemonia manjano is a popular saltwater aquarium species, but is sometimes considered an aquarium pest. This species is considered hearty and can reproduce sexually or asexually.
[WORMS link]
Euphyllia sp.?
Common name:
Hammer coral
Known commonly as “Hammer coral” in the aquarium trade, Euphyllia is a type of stony coral and so has a hard skeleton. The species found in Pearl Harbor is characterized by long polyps that branch out at the top to resemble tiny hammers.
[WORMS link]
Rhodactis sp.
Common name: Mushroom coral
Little is currently known of this corallimorph found in Pearl Harbor. Lack of genetic reference material makes positively identifying it to species difficult however, a corallimorph of the same genus has been overtaking reefs in Palmyra Atoll.
[Rhodactis in Palmyra] [WORMS link]
Rhodactis sp.?
Common names: Mushroom coral
Little is currently known of this corallimorph found in Pearl Harbor. Lack of genetic reference material makes positively identifying it to species difficult however, a corallimorph of the same genus has been overtaking reefs in Palmyra Atoll.
Rhodactis in Palmyra
[WORMS link]
While all species are of concern, Unomia has far outpaced the growth of the others, spreading in thick mats that now cover upwards of 100 acres in Pearl Harbor. Unomia lacks natural predators in Hawaiʻi and can easily fragment and be transported by currents or disturbance by human activity. The invasiveness of Unomia has been proven in Venezuela where it was introduced in the early 2000s. There, Unomia’s fragmentation abilities have allowed it to spread rapidly and dominate large swaths of the country’s coral reef habitat, covering between 30 and 80% of sites surveyed and far outpacing native corals and other benthic species.
Unomia takeover in Venezuela
Octocorals in the media
Navy works with local partners to eradicate invasive species
Ways To Help
Stay Informed about local efforts
The “Don’t Let It Loose!” campaign is part of a national effort to discourage people from releasing pets and plants into the wild. The campaign emphasizes that most pets do not survive when released and often suffer before dying, as they are typically unable to find food or shelter and become easy prey.
Reporting, Amnesty and Disposal Guidelines
The Hawaii Department of Agriculture’s Amnesty Program allows individuals to voluntarily surrender illegal animals and non-native species without facing penalties. Surrendered animals can be taken to designated locations, including humane societies and quarantine offices, and are assured not to be euthanized.
The Hawaii Department of Land and Natural Resources provides detailed instructions for reporting aquatic invasive species. It encourages individuals to contact the Division of Aquatic Resources with comprehensive details of their sightings, including date, time, location, and a description of the organism, ideally accompanied by photos and GPS coordinates.
The website 643pest.org, along with the 643-PEST telephone hotline, is a service provided by the State of Hawaii to manage reports of new pest sightings. This initiative is a collaborative effort involving the Hawaii Invasive Species Council (HISC), the Hawaii Department of Agriculture (HDOA), and the Hawaii Biodiversity Information Network (HBIN) project of the University of Hawaiʻi-Pacific Cooperative Studies Unit (UH-PCSU). The platform allows individuals to submit detailed reports of pest sightings, including images and location details.
The “Eyes of the Reef” initiative, detailed on eorhawaii.org, offers a straightforward platform for individuals to report observations of coral bleaching, coral disease, Crown-of-Thorns Sea Stars (COTS), and marine invasive species in Hawaiʻi.
Hawaii has strict laws regarding the importation, sale, and collection of marine animals. Some animals that may be allowed as pets in other states or countries may be restricted or prohibited in Hawaiʻi due to our sensitive biodiversity.
Citizen Scientists
iNaturalist is a social network for naturalists, providing a platform for individuals to record, share, and discuss their observations of plants and animals. iNaturalist serves as a valuable tool for anyone interested in nature, from amateur observers to professional scientists, fostering a global community of nature enthusiasts and researchers.
The “Eyes of the Reef” initiative offers a simple and inclusive membership process.
How: Taking Action and How You Can Help
Increase awareness about the dangers of AIS and promote campaigns like “Don’t Let it Loose” (Link).
Formed in 2023, this multi-agency group aims to address the issue of invasive octocorals in Pearl Harbor.
Follow news updates and press releases on the situation. Some resources include:
Navy Partners with State and Federal Agencies
New Invasive Species Imperils Hawai`i’s Aquatic Ecosystem
Dangerous Invasive Coral Species Found in Pearl Harbor
Support funding and efforts to address this issue and prevent large-scale environmental devastation in Hawai`i.
By understanding the what, where, when, why, and how of the invasive coral situation in Hawai`i, individuals can take informed actions to protect and preserve the invaluable coral reefs for future generations.
Where: Location of Discovery
The unidentified xeniid octocoral was first detected in Pearl Harbor during benthic surveys in 2020. By 2022, it was identified as Unomia stolonifera, with an additional octocoral species found nearby identified as Capnella cf. spicata. Neither of these species had been reported in previous Pearl Harbor surveys.
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