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Nature & Environment

A variety of wildlife can be seen as you walk the Taff Trail.

The River Taff - A Tale of Recovery

In August 2011 the River Taff was named one of the Top Ten Most Improved Rivers in England and Wales, having shrugged off its industrial past to become a haven for wildlife, walkers and anglers once again.

This river was at one time almost devoid of life, its waters blackened by pollution from local industry and households.  Chemical waste and sewage flowed into the river unchecked, and acidic water drained from the coal mines, dumping thousands of tons of colliery waste into the river each year.

Recent decades have seen a seen a dramatic recovery, with greater control of waste disposal, pesticides, and the decline of the coal mining industry.  Life has slowly returned to create the diverse and thriving ecosystem.

Invertebrates - The Heart of the Freshwater Ecosystem


The first animals to recover were the aquatic invertebrates, such as mayfly, caddis fly and shrimp.  These tiny creatures spend much of their lives unseen in the river
sediment but are nonetheless at the heart of the freshwater ecosystem, providing a source of food for a host of other wildlife.

Being highly sensitive to pollution, aquatic invertebrates are often likened to the canaries of the coal-mines.  When pollution enters the water, a drop in invertebrate numbers will soon be detected downstream, giving an early warning signal that dangerous pollutants are present, and allowing the source to be quickly tracked down.

Here on the Taff you are most likely to see species such as the Large Dark Olive and the Pale Watery, emerging as flies in the spring and summer.

Recovering Fish Stocks


Clean water and plentiful invertebrates have allowed a healthy population of Brown trout, Atlantic salmon and other fish to flourish, helped along the way by fish passes and other habitat improvements.

Testament to these improvements, in 2009 a radio-tracking project confirmed the presence of Atlantic salmon in Merthyr Tydfil for the first time in 200 years, and the town played host to a fly fishing championships.

Atlantic salmon, the 'King of Fish', spend the first years of their life in a freshwater
river, only later becoming capable of life at sea.  They then travel thousands of miles, to spend several years taking advantage of rich food supplies in the North Atlantic.  As adults they navigate home to the exact same river in which they hatched, to spawn and complete the amazing cycle.


The Top of the Food Chain


Fish are a source of food for a variety of river birds and mammals, none more famous and elusive than the otter.

Hunting mostly at night, otters can sometimes be spotted here at dawn or dusk, but are most often identified by the presence of their droppings, or 'spraints'.  Look out for dark patches of fish scales and bones on prominent rocks along the river, where an otter has marked its territory.

The dramatic comeback made by otters in recent years is another testament to the River Taff's recovery.  Their occupation of suitable sites along the river has increased by over a quarter in the last decade, demonstrating a positive growth in their numbers and range, and a real success for conservation efforts.

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Tel: 01685 727474
Last updated: 30.03.2012
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