Rivers in crisis Who Cares? Last summer saw rivers across the state suffer incredibly, and extreme dry provisions were introduced in the north east of the state. The iconic Break O’Day River ceased to flow; below local angler Howard Jones gives a back story. Howard has fished the Break O’Day since the late 1970s and its demise motivated him to become a member of Anglers Alliance Tasmania (AAT). Having received numerous reports of declining river health from anglers around the state, AAT is intent on working with other recreational water users to initiate a campaign to seek greater monitoring and protection of our waterways. AAT is keen to receive examples of both negative environmental impacts and, more importantly, examples of projects or initiatives which have led to better river health, to act as exemplars to improve land management practices.
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t a time of changing climate and rainfall patterns amid burgeoning agricultural expansion, many anglers and recreational water users are becoming concerned about the health of Tasmanian rivers and streams. The Break O’Day is an example of a struggling Tasmanian river. The Break O’Day River rises in the hills behind St Marys and flows into the South Esk near Fingal. Sadly this river has faded from a fishery written about by renowned angling authors like David Scholes, even visited by overseas anglers every October for the mayfly rise - to a waterway deemed “unfit for trout to thrive in” by the IFS in 2014. Last summer it completely ceased to flow and was reduced to a series of warming pools and broadwaters.
The Break O’Day River Our real concerns crystalized when club patron Len Smith, a fisher on the Break O’Day River for some 50 years, having fished alongside Scholes et al, insisted it was poor trout stocks and not his increasing age which had led to falling catch rates. Len wouldn’t let up, and by 2007 letters had been written to IFS, permissions had been sought from land owners and an Electro Fishing Survey took place at various sites along the Break O’Day in April of that year. Despite confident assurances from IFS staff only 2 pygmy perch, several eels, a tench and 1 trout were stunned or netted and so the IFS agreed to establish a stocking program. Initially 400 adult fish were tagged and transported to 3 sites. The following May 10,000 fingerling trout Fishing News - Page 36
The Break O’Day ran dry in 2019-20 and was just a series of pools. were finclipped and released into the Break O’Day in June and another electrofishing survey undertaken, sadly finding no evidence of any tagged fish. Stocking continued through 2009 and 2010 and a follow up survey again failed to record any previously stocked fish. Logbooks distributed to anglers indicated only a handful of tagged or fin clipped fish were recorded. Stocking continued with both fry and adult transfers into 2014. With little evidence of significant improvement in catch rates IFS informed the club that stocking of the Break O’Day River would cease as fish were failing to thrive due indeterminate water quality problems. A written request for IFS support to ascertain what the water problems were went un-answered and subsequent conversations with IFS staff highlighted their incapacity to address the issue. So, how can a river rising in the remote highlands of NE Tasmania go from a fishery lauded in Angling Literature, decline to such an extent that the Inland Fishery Service considers the waters unfit for trout to thrive, in Len’s life-time?
A sad demise For the Break O’Day River it has been a death by a thousand cuts, as many factors may have contributed to the decline in water flow, quality and impacts on the aquatic environment. A free-range pig farm at Gray (since closed) coincided with the first major signs of increased turbidity and algal growth in the Break O’Day. A new sewerage plant routinely overflowed in extreme weather events leading to trials to spray “waste water” onto adjacent farmland.
Coal Mining has shifted from underground to open cut operations sited close to headwater streams. A proliferation of instream headwater storages both for small-holdings and larger properties, limited inflow. The last 30 years has seen an incredible change in land usage. Once principally a grazing region, plantation forestry brought extensive land clearing and spraying regimes. When such schemes foundered, farmers cleared again to return land to productive use. More recently, investment in irrigation has boomed, leading to greater water extraction, increased nutrient, herbicide and pesticide application and more intensive stocking. In-stream dams on headwaters trap winter flows to provide water to be conveyed down-stream to suit farming needs in summer, drastically altering seasonal flows.
Climatic Change Rapidly changing climatic conditions, particularly seasonal rainfall patterns, are also having major impacts. Less frequent minor rainfall periods, and irregular but severe convective events have confirmed climate predictions. Periods of low flow have become extensive and increasing temperature profiles threaten the viability of aquatic organisms. Dissolved oxygen levels are compounded by nutrient run off, increased turbidity and temperature rise. With so many small headwater dams, vital flushes of the river at times of stress provided by lesser falls have been eliminated. Deluges causing extensive damage to both river banks and floodplain infrastructure have increased in both frequency and intensity. Tributaries of the Break O’Day have limited areas of riverbed suited to trout spawning. Unfettered access
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