|
Let us just consider for a moment the first two
threats on the list. Gyrodactylus salaris, a
parasite which infects the skin and fins of
salmon, trout and other types of fish in
freshwater is barely visible to the naked eye.
The effects of this parasite are so serious that
salmon stocks have now been lost completely from
more than 20 Norwegian rivers, with the
particular races of salmon in the affected
rivers being lost for ever. Gyrodactylus salaris
does not occur in UK rivers but experiments
carried out in Norway have shown that Scottish
salmon, like those in Norway, are killed by the
parasite. It could have a devastating effect on
our rivers, their inhabitants, those who depend
on the rivers for a livelihood and those who
enjoy the sport these rivers provide. This
article is not intended to become a treatise on
this parasite but it does represent a very real
threat which could inadvertently be introduced
by salmon fishermen travelling abroad or by
salmon farmers. Further information can be
obtained on line from the Fisheries Research
Services Marine Laboratory website:
www.marlab.ac.uk Go to the section on
Information Resources – External Publications to
download the SEERAD/DEFRA publication on this
subject. Here is something we can all do: take
the appropriate precautions.
Why should climate change affect the health of
our salmon stocks? We have spoken to a lot of
salmon fishermen and fishery owners this year
and a common concern seems to be that whilst
there seem to be reasonable numbers of returning
fish, some, particularly grilse (1 sea-winter
salmon), are very small. Why should this be?
Small size suggests that these fish are not
finding the nourishment they need when at sea.
The fish’s genetic instinct appears to guide its
migration to certain areas of the North Atlantic
to feed on krill, shrimps and prawns which
should enable its rapid growth and development.
These creatures thrive in certain cold water
conditions. Climate change may already be
causing a rise in sea temperature in the areas
to which the young salmon migrate. They may not
find the krill and shrimp in
|
|
the traditional migration areas. There is a
limited amount one can do at an individual level
but spreading the word and creating greater
awareness will all help to encourage the
politicians we rely on to help fund research and
reach international agreement on climate change
and other issues affecting the health of salmon
stocks. Pioneering work part-sponsored by the
Atlantic Salmon Trust was carried out in 2005 by
the team aboard the Fisheries Research vessel
Scotia. Funds have been allocated this year to
support further essential research under the
SALSEA (Salmon at Sea) programme, a major
public/private partnership endorsed by NASCO:
www.salmonatsea.com For more information on
the Atlantic Salmon visit the website of the
Atlantic Salmon Trust
www.atlanticsalmontrust.org
This may all sound rather a gloomy outlook. It
is not intended to be: we remain optimistic for
the future of salmon fishing in Scotland. It is
a good thing however to be aware of threats and
perhaps therefore a little better armed to deal
with them.
And to the most important question for the
fisherman and another important factor at the
root of river catch returns: what makes the
salmon take the fly? One man thinks he has the
answer. The author of this article recently
attended the Scottish launch of Andrew Bett’s
book ‘Trout, Salmon and the Evening Rise – The
Barometric Breakthrough’. Mr Bett has carried
out research over a seven year period on the
River Carron in Ross-shire and has concluded
that Salmon take best on a rising barometer. He
believes that this is a conditioned reflex
arising from feeding patterns when the salmon is
a parr or smolt feeding on insects which hatch
in the river when the barometer is rising. He
also states that shrimp move higher in the ocean
and become more accessible to salmon feeding in
the ocean when the barometer is rising. Mr
Bett’s book is a fascinating read containing an
interesting theory and he has some persuasive
evidence. But will you abandon your day’s
fishing just because the barometer isn’t rising:
I think not. The challenge may just be a little
greater!
|
|
