Seasonal smells from Princess Royal Harbour
Released 21 Oct 2009
The bright green algae are known as Enteromorpha and Cladophora and are flourishing as a consequence of the good spring rains and warmer conditions. Enteromorpha has also been reported in the Leschenault Estuary this spring.
They may also have noticed a challenging 'seaside smell' a result of mainly stranded Posidonia seagrass leaves decomposing after being washed up on the shoreline and being exposed by spring low tides.
The Department of Water has received calls from people concerned about the algal blooms and the smells being emitted from the western end of the harbour.
Environmental officer Karen McKeough said that it had been several years since Princess Royal Harbour had seen this localised spring growth.
"With a good wet spring, we have seen a combination of freshwater, nutrients and warmer conditions combining to encourage near shore algae growth," Ms McKeough said.
"The macroalgae, Enteromorpha and Cladophora, are both bright green in colour at this stage and readily visible from the western shore. These are naturally occurring species that have no risk to human health, but can create environmental and amenity impacts.
"The existing smell is mainly due to washed up seagrass leaves, decomposing in saturated conditions and being exposed with the low tides.
"This is a natural process and has always existed in the harbour. However, this year we have the nearshore green algal growth that can add to these smells, by being washed up on the nearby shore."
The presence of the macroalgae is a reminder that what happens in the catchment impacts on the harbour, and that everyone can help to protect our waterways, Ms McKeough said.
"Be careful when using chemicals and fertilisers in the garden, don't discharge contaminated stormwater into drains, use low phosphorus detergents - especially those areas that are still on septic tanks, keep animal waste away from our waterways and report pollution events. Remember what goes down the drain, ends up in our harbour," she said.
Contact: Peter Collins
Phone: (08) 6364 6848 / 0434 603 441