Lakes Although there are hundreds of lakes in Snowdonia, Llyn Tegid is possibly the most important where recreation and conservation are concerned. This is the largest natural lake in Wales and the river Dee flows through it. It’s 10.24km² [or 1,120 hectare, 4 miles long (6km) and ¾ miles wide (1km) ]

SSSI / RAMSAR / SAC. Three labels, one lake of international importance because of • the wildlife; the Gwyniad, Glutinous snail, Otters, and water plants • it’s a Mesotrophic lake. These lakes have more macrophytes in them and therefore a greater variety of water plants which leads to a greater variety of other species living nearby. • Its natural beauty; • The use of the lake for water sports; • It plays an important role in the management of the Dee river system and for water supply . The Dee is the most regulated river in Europe

There are two unique species within Llyn Tegid that are of national importance. Y Gwyniad . ( Coregonus lavaeretu s ) This is a fish that’s been in the lake since the Ice Age. It’s a type of fresh water herring, loves very cold water and lives at a depth of 80ft. The eggs are laid on gravel foreshores. Glutinous Snail ( Myxas Glutinosa) This snail was thought to have disappeared from Llyn Tegid in the 1950’s, but a population came to light during a survey in 1998. This freshwater snail is one of the rarest in Europe. It has a translucent mantle which extend over the shell when it feeds so that only a very narrow rim of shell is visible. It lives on algae on the cobbled foreshore which is found on some of the lake shore. Additionally, 14 species of fish, salmon and trout and 129 species of birds can be found here.

How do you protect the Lake? Snowdonia National Park Authority owns the lake bed, although the Environment Agency owns the water! Other organisations also work together to protect the lake in various ways. Countryside Council for Wales ; CCW are responsible for the site management plan. Environment Agency; The EA is responsible for the quality of the lake water. They also control the Dee river regulation system . This provides drinking water for Chester and Merseyside and areas of North West Wales and attempt to reduce flooding along the river system. Farmers; These own the land on either side of the lake. Any pollution from their land flows into the lake. Blue green algae can affect the lake in the summer caused by too much phosphate being washed into the lake. Agri-environmental schemes can be all important in reducing its impact.

Keeping the balance; conservation and enjoyment Llyn Tegid attracts many leisure users, both locals and visitors. Most visitors arrive by car and stay for a short while only. Others stay in the local area or camp by the lake. Too many visitors however and the fragile balance between conserving and enjoying the area can be lost.

Example 1; Water sports and Triathlon The lake is used for a variety of water sports. These are managed by the national Park Authority through a system of licensing and special permission (concessions) SNPA owns four car parks around the lake. Every September a Triathlon is held in Bala and around 800 people take part. All of these stay locally and eat out over the weekend; such an event is important to the local economy. In the last two years the Triathlon was nearly cancelled due to blue green algae affecting the lake. Three sailing clubs are licensed to use the lake and a variety of outdoor centres use the lake for water activities and educational use. Equipment can also be hired from a private company located close to the wardens office and specialist equipment stores have been opened in Bala, the local town. Changing and shower facilities are also available at the north eastern edge of the lake. When the number of lake users is high, the number of fishing permits sold is low. When the number of water activity permits sold are low, more fishing permits are sold. I wonder why? Due to the status of the lake, only rescue vehicles are allowed on it, as power boats and jet skis are not allowed. These would create far too much damage.

Example 2; Access for all As an Authority we strongly believe in access for all in Snowdonia. However, due to the nature of the land this is not always possible. At Llangower access has been created for wheelchair users down to the lake. Gates and a new path allow users to cross the Bala Lake railway and improve- ments have been made to access a jetty so that wheelchair users can fish safely from it.

Example 3; Toxic bloom When the blue green algae blooms under the right conditions, water sports have to be suspended. This is detrimental to the local economy. Eutrophication mean that too many nutrients (often chemical ones) have reached the lake. Blue green algae (diatoms) thrive on this and grow to the surface where they prevent natural light from reaching other plants; not the best thing to happen when protected species depend on it. This means less food for other creatures within the food chain, the type that the Gwyniad feeds on and so the entire food chain is affected. The Llyn Tegid project studied the ecology of the lake, as well as its trophic status , the available nutrients and algae (diatoms) within. The entire catchment of the lake was studied. Welsh Water have invested in ‘phosphate extractors’ at their treatment works in Bala and Llanuwchllyn to try to reduce the amount entering the lake and thus the presence of algae. Work with local farmers to reduce access by animals to riverbanks has also been done. This prevents erosion of the bank. Grants have been provided for farmers to do mitiga- tion work on the farm yard as well to prevent runoff from slurry and fertilisers reaching rivers which flow into the lake. Work on moorlands nearby to close ditches will also reduce the amount of nutrients and carbon reaching the lake. Together, all these projects will improve the quality of the lake for the benefit of Task 1. Toxic Bloom The diagram shows the connections between Llyn Tegid, it’s immediate surrounding and humans. 1. Describe how people use the lake. 2. Explain the impact of humans on Llyn Tegid. 3. What would happen to the Gwyniad if the nitrate levels increased? 4. Draw a diagram similar to this one showing what would happen to the food chain if more phosphates were added to the lake. ? 5. How could you prevent toxic blooms from af- fecting the lake in the future?

Task 2. Keeping the balance

The map shows important information for visi- tors and others about Llyn Tegid. You have been made responsible for creating a management plan for Llyn Tegid. You must take heed of the National Park’s purposes whilst creating the plan.

To protect the Glutinous snail and the Gwyniad you need to consider preventing people from accessing some areas around the lake e.g. • Active zone with access for all where you can sail, wind surf, canoe, picnic etc. • Buffer zone with access to fewer people and activities such as bird watching and walking only. • Remote zone where you would try and discourage people to protect the environment. Decide if you need two or three zones. On a map of Llyn Tegid, show how you would ideally divide the area into two or three zones. You need to inform the visitors about the new arrangements. Create an information leaflet providing them with the detail and explaining the importance of Llyn Tegid.