Archive for the ‘River Report’ Category

A visit to the Rottal Burn

Sunday, July 8th, 2012

These bulletin blogs represent news about Finavon and the South Esk, and my views as a riparian owner. They are not the views of any other organisation, nor are they designed to promote the interests of any individual or organisation other than Finavon Castle Water and factors affecting the fishery. Tony Andrews

The Rottal Burn drains the north side of Glen Clova through the Kennet Burn, two burns off Finbracks (2,478′) and another two burns from the northwest. These 5 burns join together above some waterfalls to form the Rottal Burn, which flows from just upstream of Rottal Lodge for about one mile before joining the South Esk between Drums and Kilburn. The Rottal is a sizeable burn with excellent substrata of gravels and cobbles, ideal for spawning salmonids. Like many of the South Esk’s tributaries the Rottal Burn has been abused to allow drainage of adjacent farming land. In the case of the Rottal Burn the damage caused by derdging was the removal of virtually all juvenile salmonids habitat.

The Rottal Restoration Project is supported by the South Esk Catchment Management Partnership, which includes the Esk Rivers and Fisheries Trust, SEPA, Angus Council, SNH, the Forestry Commission, the Cairngorm National Park Authority and others. But the accolade must go to Marshall Halliday, Director of the Esk Rivers and Fisheries Trust, who has driven the restoration from Day One. It is an innovative and pioneering project, and a wonderful boost for everyone who loves the River.

Rottal Ditch

The Rottal ‘Ditch’. Great flow, clean water, terrific spawning cobbles and gravels, but nowhere for little fish to grow up in safety.

There was a nice report in The Courier on the 16th of June describing the Esks Fisheries Trust’s project to restore the Rottal Burn. This important upper catchment tributary was severely damaged by a dredging operation in 2003, preceded by alterations to its course over two centuries. Fortunately, the original course of the burn is recorded in eighteenth century maps, and they have provided the inspiration for the restoration project. In an alluvial plain, as Glen Clova is, tributaries move about, so any naturally formed river or stream course is likely to have changed many times over the centuries. Nevertheless, the 18th century map gives us the most recent of these natural morphological changes, and there is merit in that as a starting point.

The purpose of the project is habitat enhancement, but not only for wild salmon and sea trout. In the South Esk catchment the freshwater pearl mussel Margaritifera margaritifera is a target for conservation, supported by its EU protected status. The parasitic relationship between the larva of the mussel (Glochidia) and upstream migrating salmon and sea trout, where the larva resides in the gills of the fish, before dropping off into upstream gravel locations to establish new mussel colonies, or strengthen existing ones, is a major justification for the Rottal project. A real success measure would be to find a new colony of MM in the burn following completion of the project.

Rottal ditch

This photograph shows the existing Rottal Burn downstream of the bridge on the north road of Glen Clova. Although the Rottal Burn is an ‘alt’ (i.e. with waterfalls impassable to migratory fish) the available spawning and juvenile potential habitat, quality of gravels and cobbles, and flow in the burn, make it a very important upper catchment tributary for all of its length downstream of the waterfalls. If the outcome of the Rottal restoration project is good quality habitats for both spawning and juvenile growth, the project will have been worthwhile, and that is before taking into account other benefits from the enhanced local environment.

Rottal confluenceThe existing confluence of the Rottal Burn with the South Esk in Glen Clova. This photograph shows the depth to which the Rottal Burn was dredged in 2003, the effect of which was to lower the water table in the vicinity of the burn in its lower reaches. The immediate riparian habitat was damaged by loss of the ‘sponge effect’, as well as in-stream habitats for juvenile salmon and sea trout. One big advantage of the restoration project is that salmon and sea trout are already using the gravels and cobbles of the Rottal Burn to spawn. With improved juvenile habitats after completion of the project the survival of fry to parr to smolts should improve. We might expect S2 and S3 smolts from the restored burn.

The photographs above show how the existing dredged channel of the burn has reduced it to little more than a high energy ditch, albeit with some very good quality cobble, suitable for spawning salmon. The problem as far as migratory salmonids are concerned has been the lack of habitat for fry and parr. With bankside foliage removed and the burn reduced to a shallow high energy riffle over gravels and cobble, there are no pools or refuges for little fish as they grow bigger.

Glen Clova is, or should be, rich in wildlife. The restoration of the Rottal Burn will provide additional wetland habitat for, amongst others, various species of wading birds such as curlews, snipe, oyster catchers and green plovers (lapwings). Amphibians such as frogs and newts and a wide range of species of invertebrate, including many species of lepidoptera, will also be encouraged to return to levels of natural abundance. After completion of the restoration project, the existing deep drainage channel of the burn will no longer exist, resulting in a raised water table, encouraging wild flowers, grasses and reeds, and thereby improving the adjacent riparian habitat.

The photographs below show how the Rottal Restoration Project has approached the problem of ‘kick-starting’ the morphological processes that will, over time, lead to a natural sequence of riffles and pools through a series of bends and changes in gradient. It is important to recognise that an artificial stream bed, as will be the situation in the Rottal Burn on completion of the project, will not be the final product, because the forces of natural flow variations, especially in times of spates, will have the ultimate say in sculpting the bed of the stream, eroding banks and depositing gravel bars. But the imaginative, sensitive and at times, subtle, work done by McIntosh contractors of Echt is giving natural morphology a great start. I am in no doubt that, when trees and shrubs grow up along the banks of the burn, and pools on corners develop deeper pockets where small fish can escape from predators or shelter in times of spate, the burn will have significant holding capacity for juveniles.

Rottal Burn Project

These photographs show phase 1 of the Rottal Project completed. It involved sculpting the course of the burn, derived from old maps that showed the course of the burn in the 18th century. The contractor has not been tempted to make dramatic changes, and instead has chosen to make a fairly shallow channel which meanders along and around old contours to the east of the canalised section of the burn downstream of the road.

Of course Phase 2 of the restoration will require the filling in of the canalised or ‘ditch’ section so that the flow of the whole burn can be added to the limited flow that is currently piped into the new course of the restored burn. That will take time, and will probably be quite messy, especially in wet weather. But in this part of the world one year makes a terrific difference; with another’s summer’s growth and more tree planting done, the new burn course will settle in quickly and, from my own experience I would guesss that inside five years it will look as if it was never any different! Trees, bankside foliage and natural morphology will soon make the Rottal Burn what it once was.

The new confluence with the South Esk is about 300 yards downstream of the current confluence. Phase 2 of the project will probably take place in early September. Between now and the beginning of Phase 2 a gentle flow of water runs through a pipe from the canalised section which has had the effect of cleaning the gravels and cobbles in the top 300 yards or so of the restored section. It is deeply reassuring to see the clean gravel there, although further down the restored section, nearer to the confluence, there is still a predominance of gritty silt. If the September date is met, and Phase 2 completed during that month, it will lead to gravels and cobbles being cleaned down the whole length of the burn by the end of October, providing every chance of salmon spawning there in November and December 2012.

Rottal ChannelThe photo above shows how the contractor has started the morphological process ‘by suggestion rather than statement’. The point is that he has created a situation where natural morphology can take over and form the new burn. It is a clever and subtle piece of landscape engineering, and deserves recognition for not taking the engineering part of the project too far.

Channel

Another view of the sculpted channel waiting for a full flow of water.

Bends & contours

Bends in the lower section of the burn, just upstream of the confluence with the South Esk, use natural contours (in this photo glacial deposits) taking the Rottal Burn back to its original meandering course.

 

Rottal bends

Looking towards the confluence with the South Esk down the freshly sculpted channel of the original course of the Rottal Burn

New confluence

 This is the newly made confluence of the South Esk with the restored channel of the Rottal Burn. The total length of the new channel, following the flood plain contours and meandering towards the river with bends and gradients, is about 1000 yards; One thousand yards of spawning and juvenile fish habitat, perhaps for our spring salmon. If the burn were to produce 1000 smolts every year, which is certainly possible, there could be another 50 spring salmon into the South Esk!

Floods, fish & a big fish lost.

Sunday, July 8th, 2012

These bulletin blogs represent news about Finavon and the South Esk, and my views as a riparian owner. They are not the views of any other organisation, nor are they designed to promote the interests of any individual or organisation other than Finavon Castle Water and factors affecting the fishery. Tony Andrews

I have never seen the South Esk hold high levels of water so consistently and for such a long period in mid summer, as has happened in June and early July this year.

As I write this bulletin in the morning of Sunday 8/7, the river is fining down to a good height for night sea trout fishing, but it is likely that most of the sea trout have already taken the opportunity of good flows to migrate into the upper river and the high ground tributaries. As evidence for that bit of speculation, I note that Cortachy and Downie Park have started to catch more sea trout. Nevertheless, so far this season we have already caught 74 sea trout in FCW pools, with three over 5lbs. My impression of the 2012 sea trout numbers is that they are similar to recent years. However, the quality of individual sea trout is excellent, which tells us something about the nutritious value of prey they are finding along the coast.

I mentioned in a previous blog that my ecologist friend, Jens Christian Holst, who works at the Institute of Marine Research in Bergen, Norway, predicted that in 2012 there would be some very large MSW salmon returning to the rivers of southern Norway and the east coast of Scotland and England. There is ample evidence that his prediction is correct, with examples of an estimated 48lbs salmon from the Balmoral water, and good fish of up to 25lbs from both Esks. In fact there have been reports of big salmon from many rivers, from the Tyne to the Naver and all rivers between. Unfortunately Jens Christian also predicted yet another poor grilse run. Like all matters concerning wild creatures nothing is ever black and white, so there will be some grilse that have found good feeding in the NE Atlantic, but on the whole we can expect undernourished ‘thin’ grilse, and not that many of them. I would be pleased if his prediction concerning grilse was wrong! In the coming years, as the implications of the SALSEA project work through the system, there is likely to be better predicting of returning migrations of wild Atlantic salmon, in terms of both numbers and quality. The implications of these predictions should enable fishery managers to take informed decisions to conserve fragile populations, instead of the guesswork and delayed actions they depend on at present.

 Marcus House Pool

The photo above was taken looking downstream from the head of Marcus House Pool. The left bank is owned by Marcus Estate but is not fished by Marcus rods because of an agreement whereby FCW anglers do not fish the pool below, Breadalbane, in return for exclusive use of House Pool by Finavon rods. Marcus Estate is now on the market and the new owner may decide to retain the current agreement, or revert to the previous free-for-all, where Marcus rods virtually stood on top of the fish while fishing from the rocky north bank of House Pool, and Finavon rods waded through the best lies at the head of Breadalbane Pool.

At Finavon we have caught and released a good number of MSW salmon up to 19lbs. On Friday Alec Towns, who knows Finavon well and is an experienced and skilled fisherman, hooked a very large salmon in Beeches Pool (just above the Aqueduct on Castle Beat). When this great fish took his fly it nearly wrenched the rod out of his hands. He played the fish for half an hour or so, with strong runs down into Haughs Pool below the aqueduct, and, after coaxing it back into the quiet glide immediately upstream of the aqueduct, started to feel that the fish was tiring. By this time he had seen the fish many times at close range. It was fresh from the sea and, judging by the size of its tail and its breadth & length, was almost certainly more than 25lbs. The last moments of contact with this beautiful salmon were spent applying side strain to inch the fish back across the river (no more than 20 yards wide at that point) towards where he was standing about ten yards upstream of the aqueduct. Suddenly there was a loud “crack” as his brand new top brand rod shattered with its second section above the butt broken into two pieces. The shock of the sudden break put huge strain on the 12lbs cast and broke it at the fly. When I saw Alec afterwards he was sad and disappointed because, as he said “it was the fish of a lifetime” lost as a result of an unreliable rod. I sometimes (increasingly often!) toy with the notion of returning to the past to fish with my Sharpes impregnated, spliced cane rods!

Other large salmon have been seen. One, described by Moray as “a dolphin” showed tantalisingly in the smooth glide immediately upstream of Volcano on Milton Beat, was a very large salmon (estimated at well over 20lbs), and other fish of a similar size have been reported from Frank’s Stream and Indies Pool on Indies Beat. As I have fished in the last few days I have been aware of the possibility of catching a really big salmon. They are there, but not in big numbers. Our regular visitor and designer of the FCW website, Simon Walter, who only started salmon fishing three years ago, caught three salmon to 15lbs at Finavon, and a very pretty 8lbs fish at Stracathro on the North Esk, plus two sea trout for his week. He drove South last night, a contented and relaxed man!

In my next blog I shall report on an inspiring visit to the Rottal Burn.

TA on 8/7/2012

 

Heavy rain, lots of fish & a dirty Lemno

Monday, July 2nd, 2012

These bulletin blogs represent news about Finavon and the South Esk, and my views as a riparian owner. They are not the views of any other organisation, nor are they designed to promote the interests of any individual or organisation other than Finavon Castle Water and factors affecting the fishery. Tony Andrews

There’s been an 11 day gap since I last wrote, and much has happened. The rain just keeps coming and with it the sea trout. We caught 67 sea trout in June which is better than for 8 years. But we shouldn’t use the catch figure to claim that numbers of sea trout in the S Esk are improving because the catch at Cortachy and Downie Park has been well below par. Inshewan meanwhile is plugging away on an average return. It is however encouraging to see that the Kinnaird Beats (near the estuary) are producing good numbers of sea trout, which suggests that fresh fish continue to arrive in the river. It will be interesting to see how long the run continues. In a good year July should be as least as good a sea trout month as June. What can be said is that our 2012 sea trout are in excellent condition. Most of them are female, and healthy and hefty females produce big fat eggs, which give the new generation a great start in life.

As far as South Esk salmon are concerned, we continue to see fresh run salmon and amongst them some very large fish. Judging by the North Esk returns and reports from other rivers there has been a resurgence of MSW salmon, as predicted by Jens Christian Holst, the Norwegian marine ecologist. He argued that good feeding in some parts of the North Atlantic Ocean has ensured that some salmon achieve prime condition. Of course, because these multi sea winter fish stay longer at sea than grilse, their numbers are reduced by predation and other causes. We should therefore not expect great numbers, but we can reasonably expect the fish that do survive to be in prime condition. As an example, Moray hooked a fine salmon in Volcano, which he estimates was well over 20lbs, and that is consistent with big fish reported by CC & DP on the South Esk, and Stracathro on the North Esk, not to mention the salmon estimated at 48lbs reported from Balmoral on the Dee. As yet there are no signs of grilse, although I hear that some have been caught in the nets. With a total of 27 salmon caught at Finavon in 2012 the season so far is about average.

Intensive Agriculture and heavy rain don’t mix! Rain falling on soggy and recently ploughed fields has washed topsoil into the burns, especially the Lemno. Recent digging and straightening of the Lemno Burn above Battledykes have released huge amounts of orange coloured subsoils into the river. At first we thought that late planting of potatoes had made the soil easily lifted by the floods, but now, into July, it seems that the Lemno has become a real problem in the quantities of silt it is now regularly spewing into the river at the Red Brae. The result is that below the confluence the river is running much dirtier than normal, clogging up gravels and making fly fishing difficult for some hours after the peak of the floods. I have reported the problem to SEPA and hope that some bales of straw or similar buffers to silt movement can be placed in the bed of the Lemno channel.

As I write this on the 2nd of  July the River is purling down in full spate. By 6pm today, if there is no more rain, we can expect to be able to fish for salmon in the quieter water of Willows and the Boat Pool with a large fly and a sinking leader. If sea trout are still running it should be possible to pick them up in the tail of the Boat Pool and Willows.

Radio tagging project on the South Esk: The report from the Marine Scotland website shows that, of the 153 fish tagged to date, only 43 have been recorded. Of these, 18 have entered the South Esk and 6 dropped back below the most downstream of the receivers. On the North Esk 17 fish have entered the River and 5 dropped back. 5 fish have been recorded at Almondmouth on the Tay and 3 fish caught by nets at sea. 

Lower Boat Pool

Lower Boat Pool

The photograph above is of Lower Boat Pool in high water. This pool is the best place at Finavon to catch salmon and sea trout in spate conditions. The pool is easily waded, even in high water, from the right bank and fish lie across the full breadth of the river from Volcano ‘squeeze’ all the way down to the cauld at the tail of the pool. It is one of those places where the fish come to you!

It is important to note that these MSW salmon are among the less than 10% survivors of the outgoing smolt migration of that year class returning from the marine phase of their lives. With 110 of these 153 tagged salmon unrecorded it is inevitable that there will be some consternation at the disappearance of so many potential spawners in prime condition being ‘lost’ at the very end of their return migration. Where are they? If we think of these fish as representative of the PFA (pre-fishery abundance) of the regional return (from proven mixed stocks ie from a number of different rivers),and apply the percentages from the 2012 stage of the South Esk project to all spring fish arriving off the coast (PFA), it is a reasonable assertion that more than 70% of the PFA abundance is unaccounted for, of which some are possibly lost through predation, poaching and other causes. Real cause for concern; perhaps it is now a priority for us to get our coastal waters in order

TA on 2/7/2012