The impact on those that live in
rivers is not much researched in the UK but thanks to those countries with
hydro dams, the Scandinavian countries in particular, we have a good idea
of the benefits and detriments of flooding which, on the whole, fills the
good column rather than the bad. Fish do well because the survival rate of
the ova increases dramatically with the heavy water flows. The gravel beds
are loosened by the flows allowing more eggs to become captured in the gravel
and once safely lodged each egg gets more and better oxygenated water. More
hatching eggs equal more fry and more fry equal more juvenile fish and so
on. Expect to see a spike in wild trout of catchable size 2-3 years from
now.
The fly population looks more
endangered but actually insects are smarter than we give them credit for,
adapting quickly as they sense the onset of the floods that force them to
find safe habitat ahead of the worst of the rains. In fact, their lives to
a certain extent get easier as the range of habitat is vastly increased as
the water floods thousands of acres of water meadows and brings life to
secondary streams, ditches and ponds. Mayflies and sedges do well out of
floods, positively thriving.
For birds and animals, the picture is
more mixed; clearly any wading birds and the ducks just love it, but for
ground nesting birds, especially those who prefer a river valley, nest
building is on hold for a for a few weeks longer. Otters just love it,
end of story but these are hard times for water voles with flooded burrows
and high mortality without the warmer, dryer weather of spring. But in
general, for wildlife, who do not run their lives according to the Georgian
calendar, this is all just the natural course of life to be endured until
better times and weather arrives.
As to the fishing itself the truth is
that this is all a lot more challenging for the fisher than the fish. Here
is a strange thing about chalkstreams: you can walk them day after day in
January, February and March untroubled by the sight of a single fish. It is
as if they have all been stolen by some unseen hand until, quite suddenly,
for no apparent reason the river is full of fish again and all is well.
Eureka day has, no doubt thanks to the depth, speed and turbidity of the
flow, arrived in early April this year, a few weeks later than scheduled.
That, I think, will be the challenge this month as the fish wait out the
floods for conditions to return to what they would regard as spring
normal.
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