The rare gwyniad fish - trapped in the lake at the end of the last Ice Age, some 10,000 years ago - is in danger because its natural home is increasingly unsuitable. A member of the whitefish family, it's found only in Llyn Tegid, Bala.
Deteriorating water quality poses a threat to its future survival in the lake. A lack of oxygen in the depths of the lake in summer, caused by the growth of poisonous algae and human activity, means that it can no longer make its home in the deeper parts.
And in summer the surface waters can be too warm - so the sections of water in which it can survive have become severely limited.
The gwyniad has also come under threat from the ruffe, which was introduced to Llyn Tegid in the 1980s. This small but aggressive fish congregates around the gwyniad spawning areas and eats the eggs and young fish.
Amid concerns that the gwyniad could soon face extinction if conditions do not improve, a collaborative project was set up in 2003 between the Countryside Council for Wales, Environment Agency Wales and the Snowdonia National Park.
This year, gwyniad eggs stripped from spawning fish will again be taken from Llyn Tegid to a new site where it's hoped a new population will flourish under more favourable conditions.
"Last year seine netting was successfully used by EAW fisheries and Snowdonia National Park staff to catch 270 gwyniad fish in bitterly cold conditions," said Rhian Thomas, a CCW Freshwater Ecologist.
"However, only 31 of these were females. Eggs were stripped from these females, fertilised and then taken to a nearby lake. Children from the local school were able to observe this process and learn about the importance of conservation.
"This second phase will again involve seine netting at night in an attempt to catch more gwyniad. We're hoping to catch more female fish this year so that we can transport more fertilised eggs to the new site so as to increase the probability of survival for the refuge population."
Richard Brassington of Environment Agency Wales said: "These rare fish spend most of their time in the deeper, colder parts of the lake and it is only at this time of year that they move into shallower water at night to spawn. Our Fisheries Officers have to use all their experience and expertise to carefully seine net a small number of fish to transfer them safely to their new home. We are also working with our partners and the local community to find longer term solutions to the factors affecting the water quality of the lake."
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your comments
Geraint Williams, Birkenhead.
I noted from Nick's comments that salmon were very scarce in Bala lake. I can rememember as a child in the 1950s seeing a plaque of a 30lb plus salmon hung up in Tecwyn Rowlands' shop in the high street. The inscription read, 'caught at the alter Llangower in the 1930s'. Can anyone shed more light on it?
Fri Jul 17 10:01:04 2009
Nick, Brisbane, Australia
I read the book The Art of Angling by Kennith Mansfield vol.I (1957). On page 132 he writes of fishing in Wales. "Of the lakes, Lake Bala is the largest in Wales, and contains every sort of course fish with the possible exception of carp and bream. Trout up to 8lb. have been recorded, but salmon are rare. Gwyniad up to 5lb. frequent Bala, but they will not take a bait and can be caught only by netting." He goes on to mention a "curious humped variety of perch" that inhabits Llyn Rathllyn. I wonder how the perch has fared since 1957?
Mon Apr 20 09:56:59 2009
Alun, Cardiff
Heard on Radio Cymru tonight that they are usually between 1/2 a pound and 3/4 of a pound at most. A fish of 1 pound would be considered a WHOPPER! They are occasionally caught, but always returned and are not specifically targeted by anglers.
Wed Jun 11 09:51:54 2008
Knut Nordby,Oslo, Norway
I was curious about the Gwyniad but I now realise it is a fish, very similar to two species we have here in East Norway. Both are in the Salmon family. The largest and most commonly caught on fly fishing tackle is the "Sik",(Coregonus lavaretus). Can get to 60cm or more.The smaller one, often caught commercially in lake Mjøsa is the "Lagesild" (lake herring)(Coregonus albula).Both varieties are plentiful in lakes and rivers here.
Wed May 16 09:01:48 2007
John Williams, Willow Street, PA USA
How big do the gwyniad fish become when full grown? I assume that no-one is allowed to catch these fish so as to help save them even more so from becoming extinct.
Fri Feb 24 03:56:19 2006
