Black bream is one of the most important recreational and commercial fish species in southwestern Australia. A ‘true estuarine’ species, black bream complete their whole life cycle within an estuary, and are reliant on healthy rivers and estuaries for their survival.
I spent Sunday morning fishing on the Margaret River with my three year old son and his mate Harry. The river is so full of fish (if you know the right spot!) we had a dinner caught in about ten minutes.
The abundance of the bream is a great indicator of a healthy river. Black bream are able to cope with salinity and temperature changes that would kill many other species of fish. The number of eggs spawned by female bream in any one ‘release’ varies, depending on the size of the fish. Studies have indicated a range of between 13,000 and more than 600,000, but it’s possible that really big females produce more than one million eggs!!
Since black bream cannot migrate to other estuaries, they are reliant on a healthy habitat, a productive food chain and good water conditions to maintain healthy populations within a particular estuary. Hardy as black bream are, they can be seriously affected by water temperature and salinity changes. In many estuaries, particularly on the west coast, the impacts of environmental factors are likely to be at least as important on stock abundances as fishing pressure. Factors include loss of bankside vegetation, increased salinity arising from catchment clearing, acid sulphate soils, and increased pesticide, herbicide and fertiliser run-off. That’s why maintaining healthy catchments and estuary ecosystems is essential to ensure the sustainability of black bream stocks in the future.
Margaret River Discovery Tours
Sean Blocksidge is the owner operator of the Margaret River Discovery Company, an avid photographer, blogger and South West WA ambassador. In 2010 he won Western Australian Guide of the Year and his tours have been rated the #1 thing to do in Australia on the Tripadvisor website for the past two years.