Spiny Algae, also known as Acanthophora spicifera, is a species of marine red algae. It belongs to the family Rhodomelaceae.
This type of algae is found in various parts of the world, including Guam, Houtman Abrolhos, and Hawaii.
Where Is Spiny Algae Found?
Spiny Algae is found in several locations of:
- Houtman Abrolhos, and
- Hawaii (non-indigenous).
In Hawaii, Spiny Algae was unintentionally introduced to Pearl Harbor from Guam in 1950.
Since then, it has become the most common nonindigenous algal species in the main Hawaiian Islands.
It has been documented at three sites on the west coast of Hawai‘i Island, including Kaloko Fishpond in Kaloko-Honokohau National Historical Park, Pu’ukohola Heiau National Historic Site, and Pu’uhonua o Honaunau National Historical Park.
What Is the Ecology of Spiny Algae?
Spiny Algae is one of the most common nonindigenous algal species in Hawaii, and it displaces many native species where it’s abundant.
The success of Spiny Algae in invading benthic habitats can be attributed to:
- Its ability to reproduce both sexually and vegetatively (by fragmentation),
- Successful epiphytism, and
- Its adaptability to a wide range of hydrological conditions.
Rapid recolonization is probably due to the ability of Spiny Algae to regrow from even small amounts of residual tissue and the high rate of reproduction.
How Does Algal Abundance Work?
Algal abundance is influenced by both nutrient availability and herbivory.
The combination of high nutrient concentration and low herbivory, as in Kaloko Fishpond, promotes greater increases in algal abundance than an increase in nutrients alone.
Herbivory, therefore, appears to play an important role in preventing tropical macroalgal growth.
Is Spiny Algae a Food Source?
Spiny Algae is a palatable and highly preferred food for herbivorous fishes in Hawai‘i and has been found in the mouths of green sea turtles.
How Can We Control Spiny Algae?
Spiny Algae is a very difficult alga to eradicate, but controlling its spread and density may be feasible.
A range of approaches was assessed to control this invasive alga in Kaloko Fishpond in Hawaii. Removal techniques were labor-intensive and had limited effect.
All experiments showed a substantial initial decrease in algal density, but the long-term effect was minimal because of rapid regrowth.
What Is the Most Promising Removal Method?
The most promising removal method was the use of submerged shelters to raise local densities of herbivorous fishes. Fishes grazed the alga and quickly reduced the biomass.
However, a large number of predators and the absence of topographical structure will make it challenging to provide sufficient shelter to increase the herbivorous fish population (biocontrol) in the entire fishpond.
Does Spiny Algae Have Medicinal Properties?
Research has shown that Spiny Algae has significant cytotoxicity. This means it can be toxic to certain cells, which may have potential medical applications.
However, further research is needed to fully understand the potential benefits and risks of using Spiny Algae for medicinal purposes.
You can check out what this plant looks like over here.
Spiny Algae Characteristics
|Required Lighting:||Moderate High|
|Required Water Flow:||Moderate High|
|Is Palatable?||Not really|
|Maximum Size:||8 in (20.3 cm)|