Demand blooms for farm water safety in peak BGA season

Toxin-causing cyanobacteria

3 March 2014

Queensland farmers are urged to review their water safety strategies as the annual season for blue-green algae  (BGA) blooms reaches its peak between February and April.

Cyanobacteria and alga scientist Lindsay Hunt, from Jarvis Hunt Consultancy, said the blooms, if left untreated, could result in exposure to water that’s unsafe for crops and livestock as well as humans.

“Australia’s $32 billion food production industry already spends over $600 million on water management each year, but the potential damage of a single bloom event would have a significant impact on a farmer’s livelihood, in terms of stock and crop losses, and buying in water supplies from other sources – on top of the treatment costs,” Ms Hunt warned.

“One of the biggest issues facing farmers, and the companies they outsource their water management to, is having access to reliable, accurate data about the phytoplankton or micro-flora in their dams and irrigation systems.

“Not all blooms are created by toxin-causing bacteria and you can waste a lot of money and effort putting the wrong management plan into action if you don’t identify the real problem-causing species at the start.

“However, even non-toxic blooms impact upon the water. Fish may not be edible. The water may cause skin irritations and respiratory distress for people who are susceptible and come into contact with it,” Ms Hunt explained.

“Farm dam sediments overloaded with fertilisers can cause nutrient burns to stock, so monitoring run-off into dams requires long-term management.”

Cyanobacteria, commonly referred to as BGAs, are a group of photosynthetic microorganisms that survive and flourish in all kinds of ecosystems. They are usually too small to be seen; but when they form large colonies (‘blooms’) the mass can take on a paint-like appearance on the water’s surface.

However, not all BGAs form scums, so it may not always be obvious.  This is why reliable, timely and accurate monitoring and toxin analysis is essential

Ms Hunt said that distinguishing the many different species of phytoplankton in water requires expert training and knowledge, but not all water testing facilities are set up or have the skillset to provide accurate reports on levels of BGAs or the toxins they produce.

“Regulatory frameworks at all government levels have imposed significant strain on the budgets and resources of Queensland’s agriculture and aquaculture industries, and this cost could rise as future water supply management and security become increasingly important.

“And for the regions which rely on farming, the cost to the local economy can be devastating.

“Jarvis Hunt Consultancy has introduced new services to help farmers ensure they have access to reliable and timely data specifically about BGAs. That way, if there is a problem, the farmer or property manager can be confident of making informed and cost-effective decisions about treatment.

“We help clients dealing with phytoplankton and cyanobacteria management achieve optimum water quality. With our extensive experience working in NATA and quarantine accredited production laboratories, we can coordinate scientific analysis and solutions to help manage agricultural water supplies,” Ms Hunt said.

Jarvis Hunt Consultancy was established in 2013 in response to the growing demand for reliable, specialist services in the quest for optimal water quality, ecological balance, and sustainable management systems.

About Jarvis Hunt Consultancy www.jarvishuntconsultancy.com.au

Based in Ipswich, Queensland, Jarvis Hunt is the only consultancy in Australia offering a comprehensive package of in-house training plus specialist advice and contract-based technical services, including:

  • Micro-ecology consulting and analysis
  • Freshwater phytoplankton analysis, sampling, monitoring, training
  • Laboratory set-up, management practices and Quality Assurance
  • In-house contract counting
  • Routine microbiological analysis of water samples

Drawing on more than 15 years of experience as a practising phycologist and research manager, Jarvis Hunt’s principal scientist Lindsay Hunt is now sharing her expertise with a range of clients whose objectives are similar: understanding how micro-organisms affect water quality and finding solutions for water quality problems.

About Blue Green Algae (Cyanobacteria)

  • Blue-Green Algae (BGA) occur naturally in most marine and freshwater aquatic systems.
  • Cyanobacteria have been found in the planet’s oldest fossils and created the atmosphere that made all current life on earth possible.
  • When there is an imbalance of the levels of BGA in an ecosystem, some species can produce toxins that have serious health implications for humans, animals, birds and livestock.
  • A bloom is identified as a discernible increase in algal numbers causing changes to the water’s colour, taste, odour, turbidity, as well as impacting on the health of other aspects of the ecosystems, such as birds, fish, frogs, etc.
  • Cyanobacteria blooms can occur in any warm, still or slow-moving freshwater that contains nutrients such as fertiliser runoff or septic tank overflows, including rivers, streams, wetlands, natural and man-made lakes, dams, estuaries, inlets, bulk water reservoirs, irrigation channels, stormwater drains, sewers, and wastewater treatment plants.
  • BGA blooms usually flourish in the summer months when warmer temperatures, increased rainfall and incidence of flooding can change the levels of nutrients entering an ecosystem.
  • BGA blooms in cooler months are often caused by unusually high levels of nutrients flowing from floods and rainfall.
  • Signs of the environmental impact from BGA blooms include odour and taste changes, but the primary one is the discolouration of the water to verdant green and or vibrant blue, and a foam or scum-like layer on top of the water.
  • Dense blooms can block sunlight and consume all the oxygen in the water, killing off other plants and animals.
  • Toxins associated with cyanobacteria have been known to damage the nervous system and liver, upset the gastrointestinal system, and promote tumour growth.