Upland tarns: untarnished waters

For the most part, upland tarns are fished very lightly. A small, select band of anglers have found that peace, tranquillity and small wild browns heavily outweigh the frantic fisheries with their large, beer-bellied trout.

Fishing apart, truly spectacular scenery surrounds most upland tarns. But getting to some of these waters entails quite a hike, and unless you are prepared to spend part of the day viewing the countryside – and its flora and fauna – then stick to the heavily stocked stillwaters where access is easy.

Foods and flies

Tarns usually hold a population of small active brown trout with a few perch and even the odd pike. The water quality is slightly acidic with the result that food items are scarce. Growth rates of trout are subsequently slow.

Major factors affecting the quality of fishing on tarns are their geographic location and the severity of the previous winter’s climate. Tarns open to the sun for long periods during the day usually have more insect activity (due to the warmer water) than those in shadow most of the time. After a severe winter, the water remains cold for a long time, so fish activity is low. Don’t even attempt to start fishing tarns until May or, in some of the higher altitude waters, June so that the trout have plenty of time to recover from the rigours of spawning.

Tarn-born trout are opportunistic and quickly latch on to caddis, midges, shrimps, snails and corixas. Many tarns hold a head of perch on which trout often prey. Virtually all the larger browns even eat their own fry and fingerlings.

Terrestrials are another major food source throughout the summer months -don’t underestimate the importance of beetles, heather flies and cranefries: all types are blown on to the water surface.

Like other stillwaters, deep-water areas are generally devoid of aquatic food forms. Again, it can’t be stressed enough that trout mainly feed in shallow water.

Generally, the one distinct advantage an angler has when fishing this type of water is the meagre amount of food available to trout. Though there are many forms of food, the over- all amount is small. Consequently, the fish are generally over-eager to take any food that comes their way – suitable imitations are rarely refused, though these waters are not the place to try new, sophisticated dry flies and nymphs.

Flies which are more likely to produce fish are suggestive patterns such as the Black Pennell, Gold Ribbed Hare’s Ear, Greenwell’s Glory, Bibio, Invicta and Zulu. Avoid using the large attractor lures like mylar-bodied tandems; they just don’t work. A small Ace of Spades (size 12) or similar fry-imitating lure, however, can catch fish. Don’t go for the usual bright concoc- tions; stick to the more sombre-coloured perch fry imitations.

Structure and wind

Rock outcrops, large boulders and weedbeds that border deep water, and so offer security, are likely fish-holding places. Also be on the lookout for inlet streams which build up food in channels. Although few and far between, weedbeds are always worth special attention as nymphs, snails and fry gather here, seeking cover and food.

Another major factor to consider is the wind. The downwind bank is always the best bet on any Stillwater, for certain food items are usually concentrated in this area. In some situations, however, such as when a breeze is blowing terrestrials on to the upwind shore, the fish are quick to set up station and usually betray their presence by surface activity at the interface of rippled and calm water.

Imagine a typical tarn

You arrive at the mid-sized tarn on a cloudy day in August to find the water almost completely flat calm — with only the lightest ripple in the centre and no sign of any fish. The first task is to thread the slow sinking line (WF6) through the 934ft (2.9m) fly rod, and then attach a 10ft (3m) leader (with two droppers). A Hare’s Ear Nymph goes on point. The middle dropper is a Greenwell’s Glory, and the top dropper is a Bibio.

You begin fishing a deep pocket of water. The area looks promising because there’s a lush blanket of weed about 22m (24yd) out from the shore. The trout take advantage of the weeds for cover and the deep water for safety and low light levels.

Half an hour later, a spirited half pounder (0.23kg) nails your Hare’s Ear on the drop – your first fish.

Moving to the western bank, you see the first rise of the day about 30m (33yd) along the bank in shallow water. Off comes the sinking line and on goes the floater in anticipation. Then you wait.

Some small dark olives are hatching regularly, so you attach a size 16 Greenwell’s Glory (dry). You cast, and the fly is taker immediately. This fish is followed by twc others in quick succession before the rises stop and the remaining fish retreat from all the activity. All of the trout are returned the largest of them being 20cm (8in) long.

During this activity a breeze has made distinct ripples on the once flat water some 15m (16yd) out from the bank. The sun is dipping behind the western hills and all is quiet. A good fish rises on the ripples about 50m (55yd) down the bank, then another You make a few casts, but there’s nc response.

The next few rises prove much the same Quite a lot of activity is now taking place or the bank, and it is only when you notice a struggling cranefly disappear in a large swirl that the penny drops. A quick change to a size 10 Daddy-Long-Legs, and you’re into the best fish of the day — a lovely Xilt (0.4kg) brownie. Three other trout follow – a couple more are missed — before the wind drops with the setting of the sun. The tarr is once more transformed into the proverbial mill pond, and it’s time to start making your way back across the hills to your cai before it becomes too dark.