Environment and Resource Management

Lyngbya

Lyngbya majuscula (Lyngbya) is a naturally occurring, threadlike, blue-green algae that has occurred in bloom proportions in south-east Queensland coastal waters.The Department is coordinating the response by State and local government and key stakeholders to the Lyngbya outbreak in Moreton Bay, Deception Bay and Pumicestone Passage.

The Lyngbya Steering Committee was started in 2000 to bring key stakeholders together to identify causes and implement effective management actions to reduce the risk of future Lyngbya blooms. The committee included representatives from State and local governments and other industry, scientific and community organisations. The Steering Committee was advised by the scientific expert panel of the South-east Queensland Healthy Waterways Partnership, chaired by Professor Paul Greenfield of University of Queensland.

The committee has recently been expanded into the Coastal Algal Bloom Reference Group.  As part of this coordinated effort, DERM will continue to provide the most up-to-date information on Lyngbya outbreaks and its management on this website.

Scientific and common names

The scientific name of the cyanobacterium (blue-green algae) is Lyngbya majuscula, but it is also commonly known as Mermaid Hair, Stinging Limu and Fire Weed—a name that has caused some confusion in the wider community. Fire weed was the name first given to Lyngbya by the Fraser Island community due to the similarity of its contact symptoms and the symptoms from another organism, ‘fireweed’, which is a small hydroid with stinging cells commonly found in the waters of south-east Queensland.

 

Lyngbya filament

Microscopic view of Lyngbya filament (courtesy: University of Queensland).

Basic features

Lyngbya is a toxic marine cyanobacterium (blue-green algae). It grows attached to seagrass, seaweed, coral and rocks in clumps or mats of fine, dark cotton wool-like strands 10 to 30 centimetres long. Through the accumulation of gas bubbles, clumps can rise to the surface to form large floating mats. Floating Lyngbya washes up on some beaches, often mixed with seagrass. Generally fish do not swim in areas affected by Lyngbya and tend to leave these areas to find waters that are not affected.

Floating Lyngbya

A detached piece of Lyngbya (courtesy: University of Queensland).

Where does it grow?

Lyngbya is common in seagrass and coral reef habitats in tropical and subtropical waters worldwide. However, dense blooms of Lyngbya have occurred in coastal Queensland (Whitsunday Islands, Shoalwater Bay and Fraser Island), with the most prolific blooms reported in south-east Queensland. Common bloom areas in Moreton Bay are shown below and include Pumicestone Passage, northern Deception Bay and eastern Moreton Bay.

Common bloom areas

Common bloom areas in Moreton Bay including the Pumicestone Passage, northern Deception Bay and eastern Moreton Bay.

Impacts of Lyngbya blooms

In recent years, Lyngbya blooms have impacted on the environment and people’s health.  Although the long-term impacts of Lyngbya are unknown, current scientific knowledge indicates the sheer mass and toxicity of the blooms pose a significant threat to ecosystems and their dependent economies.

The following environmental impacts have been suggested:

The following economic impacts have been suggested:

Lyngbya bloom washed onto foreshores in Deception Bay and smothering mangrove roots (courtesy: Moreton Bay Regional Council).

Causes of Lyngbya blooms

Results from the completed Lyngbya Research and Management Program 2005-2007 indicate that the key environmental conditions for Lyngbya growth appear to be the presence of bio-available nutrients including iron, phosphorus and nitrogen; dissolved organic matter; and favourable light, salinity and temperature conditions in the environment.

Land uses and management activities that alter groundwater levels and surface water runoff, in association with major rainfall events, result in significant loads of these nutrients transported to coastal waters.

Potential high-risk activities that may increase nutrient loads to the coast are linked to Lyngbya blooms. Examples include certain activities associated with agriculture, forestry, sewage treatment, industry including extraction, and urban development. The disturbance and subsequent oxidation of acid sulfate soils is also of concern, as it leads to the release of nutrients such as iron.

It is thought that blooms in Deception Bay are triggered by high concentrations of nutrients and bio-available iron being discharged into the marine environment from wet-weather surface run-off and some groundwater discharges. In contrast, blooms on the eastern banks are considered to be primarily a result of groundwater discharges or some other forms of environmental disturbance.

Causes of Lyngbya blooms - conceptual diagram

Conceptual diagram summarising the current understanding of causes of Lyngbya blooms in Deception Bay. Source: Coastal Algal Bloom Action (SEQHWP, 2008). Note: Key nutrients (iron, phosphorus, nitrogen and dissolved organic carbon) move from the catchment through surface and groundwater into Deception Bay and onto the seagrass flats. There they are sequested in the sediments and subsequently become available for Lyngbya growth or are immediately available for uptake from the water column.

Health advice

Lyngbya is a contact irritant that can produce skin and eye irritation following direct contact. In severe cases, affected skin may blister and peel off. Lyngbya has the potential to irritate any part of the body that it comes into contact with. Thus, inhalation or ingestion of Lyngbya can cause irritation to the respiratory and gastrointestinal tracts. The severity of irritation usually depends on the level of exposure.

People who have come into contact with Lyngbya may complain of a stinging, burning or itching sensation within minutes or hours after being exposed. Affected areas may appear red and swollen, and small blisters may form. Reddening and swelling of the conjunctiva of the eye and the mucous membrane of the nose can occur if those parts of the body have direct contact with Lyngbya. In view of its potential to cause severe irritation, people should avoid areas affected by Lyngbya if at all possible.

Advice to the general public

People should avoid swimming or wading in areas where Lyngbya is growing or floating in the water and should not have direct contact with material washed onto the beach.  Local councils may clear large amounts of Lyngbya that has washed onto high-use public beaches. See the contact list below to obtain local beach and swimming information.

If you have any of the symptoms listed above, and have been in an area affected by the algae, see your doctor.

South-east Queensland contacts

 

For current and historical monitoring information in Moreton Bay:

For local information, updates or beach and swimming reports for:

North Stradbroke Island and other Redland City Council related matters:

Marine Park related matters:

National Parks:

Deception Bay, Bribie Island and other Moreton Bay Regional Council related matters:

Northern Pumicestone Passage and other Sunshine Coast Regional Council related matters:

For matters relating to Brisbane City Council:

For matters relating to Gold Coast City Council:

To report incidents of pollution, fish kills or potential environmental harm:

Queensland-wide contacts

For local information, updates or beach and swimming reports, please contact the relevant local government customer service centre.

To report incidents of pollution, fish kills or potential environmental harm:

Marine Parks:

Last updated 6 July 2011

Lyngbya

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