Making the Lyme Brook a good home for the
Brown Trout!
Our native species of wild trout is the brown trout (Salmo trutta) and as well as clean water it
also needs access to a varied range of habitats. When this habitat variety is present in a stream,
it is also very good news for a wide range of animal and plant life in the whole river corridor.
Our works to improve the habitat for all wildlife on the Lyme Brook are also designed to meet
the specific requirements for the separate critical stages of the lifecycle of brown trout. As a
result, we have made sure that any trout that might successfully migrate up from the main River
Trent has access to the habitats detailed below. Each habitat type provides the best chances of
success for trout at each stage of its lifecycle.
© Paul Gaskell
Gravel introduced into Lyme Brook
During the winter months, the adult female trout digs a hollow in the riverbed
called a “redd”. This is a nest for her eggs. When the eggs are fertilised by an adult
male trout’s milt, the female then flicks gravel from the riverbed just upstream of
the nest to bury and protect the fertilised eggs. The eggs also need oxygen rich
water free from silt flowing over them to develop. This is why we introduced extra
gravel into the brook, shaped the edges of the brook and installed woody material
so that any silt is washed away.
Life Cycle Stages of the
Brown Trout
A ‘brash berm’ installed in Lyme Brook
In spring, when the alevins have absorbed all their yolk sac they emerge from the gravel as fry and begin to
feed on tiny animals in the water called plankton. As the fry grow, vertical lines appear along their bodies,
called parr marks, these help to camouflage them from predators. At this stage, they need shallow water
(approx. 20cm or less) and dense submerged structures to hide in - such as feathery tree roots and trailing
bankside vegetation. The brash berms which we have installed provide this, as well as the sedge grasses and
wild flag iris which we planted. The root masses of iris in the margins of a stream are very good habitat for
baby trout. The brash berms will also introduce a more meandering flow to the brook.
How can you help your waterways?
The Lyme Brook could suffer from pollution, and this can affect the health of the waterway and the species which live in it. Plumbing and drainage misconnections can pollute waterways. If your
wastewater or sewage is connected to a surface water drain you may be polluting your local waterways. Simply put, this would be where a toilet or kitchen pipe runs into a rainwater pipe and straight
into the Brook instead of into a sewage pipe and onwards into a sewage treatment works. Check that your property is connected correctly - as a property owner you are responsible for fixing a
misconnection. Go to www.connectright.org.uk for how to check if your property is misconnected or not.
There may be other problems with water quality which come from diffuse pollution. This is when pollutants are put into the soil or onto a road and then either seep into the Brook directly or get into a
surface water drain before emptying into the Brook. We all have a responsibility to keep our waterways clean, so please check your house for misconnections, be aware where you are tipping polluting
substances and only let rain go down a surface water drain! To report any pollution please call the Environment Agency hotline on 0800 80 70 60
For more information about how you can help your waterway’s go to http://www.groundwork.org.uk/Sites/westmidlands/Pages/love-your-river
When the eggs hatch out they are called “alevins”, these
are baby trout with yolk sacs attached, which they live
off. This stage can take a few months depending upon
the temperature. Both of these lifecycle stages live
buried in gravels. This is why clean, silt-free gravel is
needed for trout to breed successfully.