The Story of Caerlaverock National Nature Reserve (2nd edition)
For further information about Caerlaverock National Nature Reserve please contact: Reserve manager Scottish Natural Heritage Greystone Park 55/57 Moffat Road Dumfries DG1 1NP
Tel: 01387 272440 Email: [email protected]
The Story of Caerlaverock National Nature Reserve
Foreword
Caerlaverock National Nature Reserve (NNR) stretches for 16 kilometres along the north coast of the Solway Firth in Dumfries and Galloway, south west Scotland. There are few places in Scotland like this – a dramatic landscape of mudflats, sandbanks and saltmarsh, which extend beyond the reserve, into the estuary and all the way to England.
The reserve is home for tens of thousands of wintering barnacle geese; the entire Svalbard population of barnacle geese, currently approximately 38,0001 birds, return each year to the Solway Firth. Winter also attracts staggering numbers of other wildfowl and waders, such as oystercatcher, pintail and curlew who flock here to feed on the mudflats and roost on the merse (local name for saltmarsh). Summer is quieter, but it is now that one of the reserve’s most unusual inhabitants becomes active. In the shallow pools at the northern edge of the reserve, natterjack toads thrive at their most northerly location in the UK.
The saltmarshes are also notable for their landforms, which reveal processes of coastal evolution on an emerging coastline.
Caerlaverock is one of a suite of NNRs in Scotland. Scotland’s NNRs are special places for nature, where some of the finest examples of Scotland’s wildlife are managed. Every NNR is carefully managed both for nature and for people. They are great places to experience, enjoy and learn about the best of Scotland’s nature.
‘The Story of Caerlaverock National Nature Reserve’ contains background information about the reserve, describing the wildlife interest, its land use history and management since it became a reserve. How we intend to manage the reserve in future years is outlined in the current management plan.
1Count estimate from winter 2015
The Story of Caerlaverock National Nature Reserve
Contents
Foreword ii
Maps of Caerlaverock NNR iv
1 Introduction to Caerlaverock NNR 1
3 Management of Caerlaverock before it became a NNR 8
4 Management of Caerlaverock NNR 10
5 Document properties 1
iii The Story of Caerlaverock National Nature Reserve
Maps of Caerlaverock NNR
Location map2
2 Location of other NNRs correct at December 2014
iv
Boundary of Caerlaverock NNR
The Story of Caerlaverock National Nature Reserve
1 Introduction to Caerlaverock NNR
Caerlaverock NNR lies 10 kilometres (km) south of Dumfries on the north shores of the Solway Firth on the Scottish border. Covering approximately 8,000 hectares (ha), the reserve is part of the much larger complex estuary of the Solway Firth. At high tide, only the merse and grasslands are visible fringing the surrounding arable farmland. Low tide however, paints the full picture – with huge expanses of mudflats stretching as far as the eye can see. The reserve has a tremendous diversity of wetland habitats with a natural transition from bare mud and sand to pioneer and established merse (saltmarsh), leading through to neutral grassland. There are also extensive areas of reed bed and brackish and freshwater marshes.
The reserve includes the mudflats of Blackshaw Bank and Priestside Bank and part of Carse Bay. The River Nith forms an ever shifting channel through Blackshaw Bank to the Solway Firth. The merse forms part of the largest area of continuous saltmarsh in Scotland. Like the mud and sand flats, it is also part of a dynamic system that is constantly changing shape and size due to the effects of the sea, eroding and accreting as the tides come and go. It sits on bedrock of Permian sandstone that is occasionally exposed in small areas by tidal erosion.
As with much of the west coast of Scotland, the Gulf Stream keeps Caerlaverock’s climate mild and damp. Although there has been no climatic data recorded at Caerlaverock itself, average rainfall over the last 50 years at Dumfries, only 10 km north, was approximately 1000 millimetres (mm) per year, much of it falling in the late summer, autumn and winter. The coastal location of the reserve also ensures there are fewer frosts than would be expected this far north.
View looking west from the mouth of the Lochar Water
1 The Story of Caerlaverock National Nature Reserve
It is the combination and extent of mudflats and merse, together with the milder climate, that makes Caerlaverock NNR such an attraction to wildfowl and waders migrating south for winter. Barnacle geese arrive on the Solway each autumn to escape the harsh Arctic winter. Here, they feed on the merse and roost on both Blackshaw Bank and Priestside Bank. Other birds, such as pintail, oystercatcher and knot feed on the mud and sand flats at low tide, the wading birds using the merse as a roost when the sea returns to cover their feeding grounds.
As well as birds, the reserve is also home to natterjack toads. At their most northerly location in the UK, Caerlaverock has a small population. In recent years the curious and extremely rare tadpole shrimp has also appeared in shallow pools in wet summers. The merse and associated wetlands also support a number of scarce plant species such as holy grass.
These huge populations of birds, rare amphibians and wetland habitats share the Solway Firth with farmers, fisherman and wildfowlers. From the beginning, when the Duke of Norfolk was instrumental in establishing Caerlaverock as a NNR, he was keen to ensure the needs of wildlife could exist in harmony with the interests of farming, fishing and wildfowling. This philosophy is still at the heart of Caerlaverock’s management today.
Visitors have been enjoying the reserve since it was declared in 1957. It can be accessed at Castle Corner, close to the mouth of the River Nith or further east at Hollands Farm. At both car parks there are paths that provide visitors with opportunities to gain access to the reserve. From Hollands Farm a core path links from the NNR through to the neighbouring Wildfowl and Wetlands Trust reserve at Eastpark. Caerlaverock has been designated for its wildlife interest at UK, European and world- wide level. It falls within the larger Upper Solway Flats and Marshes Site of Special Scientific Interest (SSSI), Special Protection Area (SPA) and Ramsar site; and the Solway Firth Special Area of Conservation (SAC).
The recognition as a European site of international importance (SPA and SAC) means that Caerlaverock is part of a Europe wide suite of areas referred to as Natura sites. This extremely important group of sites includes other high profile wetlands such as The Waddenzee in Holland, the Camargue in the South of France and the Ebro Delta in Spain. The inclusion of Caerlaverock in such company confirms its importance as one of the best estuarine sites in Europe.
The reserve also forms part of the Nith Estuary National Scenic Area (NSA). Further details of these designations can be found through the Scottish Natural Heritage sitelink website.
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Table 1 Designations and qualifying features at Caerlaverock NNR
Feature Protected Area Atlantic salt meadows Solway Firth SAC Upper Solway Flats and Marshes RAMSAR Bar-tailed godwit (Limosa lapponica), Upper Solway Flats and Marshes SPA non-breeding Upper Solway Flats and Marshes SSSI Breeding bird assemblage Upper Solway Flats and Marshes SSSI Coastal Geomorphology of Scotland Upper Solway Flats and Marshes SSSI Cormorant (Phalacrocorax carbo), Upper Solway Flats and Marshes SPA non-breeding Upper Solway Flats and Marshes RAMSAR Curlew (Numenius arquata), non- Upper Solway Flats and Marshes SPA breeding Upper Solway Flats and Marshes SSSI Dunlin (Calidris alpina alpina), non- Upper Solway Flats and Marshes SPA breeding Upper Solway Flats and Marshes SSSI Estuaries Solway Firth SAC Glasswort and other annuals Solway Firth SAC colonising mud and sand Golden plover (Pluvialis apricaria), Upper Solway Flats and Marshes SPA non-breeding Upper Solway Flats and Marshes SSSI Goldeneye (Bucephala clangula), Upper Solway Flats and Marshes SPA non-breeding Upper Solway Flats and Marshes SSSI Great crested grebe (Podiceps Upper Solway Flats and Marshes SPA cristatus), non-breeding Grey plover (Pluvialis squatarola), Upper Solway Flats and Marshes SPA non-breeding Upper Solway Flats and Marshes SSSI Intertidal mudflats and sandflats Solway Firth SAC Upper Solway Flats and Marshes RAMSAR Knot (Calidris canutus), non-breeding Upper Solway Flats and Marshes SPA Upper Solway Flats and Marshes SSSI Lapwing (Vanellus vanellus), non- Upper Solway Flats and Marshes SPA breeding Mallard (Anas platyrhynchos), non- Upper Solway Flats and Marshes SPA breeding Mudflats Upper Solway Flats and Marshes SSSI Natterjack toad (Epidalea calamita) Upper Solway Flats and Marshes SSSI Oystercatcher (Haematopus Upper Solway Flats and Marshes RAMSAR ostralegus), non-breeding Upper Solway Flats and Marshes SPA
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Feature Protected Area Upper Solway Flats and Marshes SSSI Pink-footed goose (Anser Upper Solway Flats and Marshes RAMSAR brachyrhynchus), non-breeding Upper Solway Flats and Marshes SPA Upper Solway Flats and Marshes RAMSAR Pintail (Anas acuta), non-breeding Upper Solway Flats and Marshes SPA Upper Solway Flats and Marshes SSSI Redshank (Tringa totanus), non- Upper Solway Flats and Marshes SPA breeding Upper Solway Flats and Marshes SSSI Ringed plover (Charadrius hiaticula), Upper Solway Flats and Marshes SPA non-breeding Upper Solway Flats and Marshes SSSI Ringed plover (Charadrius hiaticula), Upper Solway Flats and Marshes SPA passage River lamprey (Lampetra fluviatilis) Solway Firth SAC Saltmarsh Upper Solway Flats and Marshes SSSI Sand dunes Upper Solway Flats and Marshes SSSI Sanderling (Calidris alba), non- Upper Solway Flats and Marshes SSSI breeding Upper Solway Flats and Marshes RAMSAR Scaup (Aythya marila), non-breeding Upper Solway Flats and Marshes SPA Upper Solway Flats and Marshes SSSI Sea lamprey (Petromyzon marinus) Solway Firth SAC Shelduck (Tadorna tadorna), non- Upper Solway Flats and Marshes SPA breeding Upper Solway Flats and Marshes SSSI Upper Solway Flats and Marshes RAMSAR Svalbard Barnacle goose (Branta Upper Solway Flats and Marshes SPA leucopsis), non-breeding Upper Solway Flats and Marshes SSSI Vascular plant assemblage Upper Solway Flats and Marshes SSSI Waterfowl assemblage, non-breeding Upper Solway Flats and Marshes SPA Whooper swan (Cygnus cygnus), Upper Solway Flats and Marshes SPA non-breeding
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2 The Natural and Cultural Heritage of Caerlaverock NNR
Estuary, sandbanks and mudflats
Since the end of the last Ice Age, some 15,000 years ago, the coastline has altered in response to changes in sea level and the supply and movement of the sediments. At this time the sea level was relatively lower than at present. Studies of landforms and sediment layers in the lower Nith valley and estuary (Smith et al., 2003) has shown that sea level rise associated with the main glacial retreat started some 8,500 years ago and ended around 6,700 years ago. Since then, the sea level has fallen, possibly in steps, reaching present levels about 1,800 years ago.
Throughout this time the currents and tides of the Solway Estuary have been shaping the subtidal sandbanks and intertidal mudflats that now form the majority of Caerlaverock NNR. This dynamic process still continues, lifting up silt and sandy sediments from turbulent parts of the estuary and depositing them where the tidal currents are not so strong. Most of the Criffel from the Nith Estuary sediment is deposited from material carried into the Solway from the Irish Sea, with fine silt and mud deposited by rivers which discharge into the estuary.
The Solway Estuary is a large, complex estuary. It is one of the least industrialised and most natural large estuaries in Europe. One quarter of the area of estuaries in north-western Europe occur in the UK, but there are only a few examples in western Scotland.
There are 3 main sandbanks within the reserve - Blackshaw, Priestside and Carse Sands, covering an area of around 7,000 ha. At some points on the lowest tides, these sandbanks are exposed for up to 5 km into the estuary. Throughout Europe and the UK, this type of habitat is widely distributed.
At Caerlaverock, gravelly and clean sands dominate the habitat. The continually shifting muds and sands also hold significant invertebrate stocks, such as mud shrimps, snails, cockles, tellins and marine worms. Mussel beds also colonise the rocky outcrops. These provide a full and varied larder for the huge assemblages of wildfowl and waders.
1 The Story of Caerlaverock National Nature Reserve
Likewise, the inter-tidal mudflats are also heavily influenced by the dynamic estuarine system. Fine sandy sediments occur in the inner estuary, and more stable and diverse conditions in the outer reaches. Salinity ranges from fully marine to estuarine in character; these gradients in physical conditions add to the ecological diversity within the reserve. The Solway is the third largest area of continuous mudflats in the UK.
The merse
Merse (the local name for saltmarsh) has also formed as the coastline has developed and changed since the last Ice Age. Like the mudflats and sandbanks, the Solway’s fluctuating currents have a significant effect on the shape of the merse, eroding in some areas, extending in others. The present day merse at Caerlaverock is a relatively new habitat - less than 200 years old. Maps from the 1850s show the sea coming up to the boundary of Caerlaverock Castle woods. Now the merse extends to 600 ha, from Kenneth Bank to the north of the reserve for approximately 10 km south and eastwards to the Lochar Water. But this is not a static habitat; the edge is currently eroding in the west and accreting in the east. Consequently, the dynamic saltmarshes of Glasswort the Solway coast are important nationally for studies of saltmarsh landforms and processes associated with an emerging coastline.
The process of merse building begins when pioneer plant species such as, glasswort gain a foothold in the mud nearest the land. As they grow they trap sand and silt among their roots and stems and the mud begins to stabilise, allowing other salt- tolerant plants such as, common saltmarsh grass and sea spurrey to take hold.
In Europe, saltmarsh habitat is widely distributed in coastal areas. The whole of the Solway represents approximately 25% of the UK saltmarsh resource and the merse at Caerlaverock is the largest continuous area of saltmarsh in Scotland.
A key reason for the presence of Caerlaverock’s spectacular flocks of barnacle geese is the combination of undisturbed roosting grounds and an abundance of grasses and clover on the merse, on which the geese feed. At high tide the merse also provides an important roosting area for the wildfowl and wader assemblages.
Behind the merse is an area called ‘The Flooders’. This is a 32ha area of freshwater marsh and reedbeds, created in part by the construction of a seawall and flood bank in 1840. The habitat is unusual for the area and supports extensive stands of common reed, and a diverse range of wetland plants.
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Fauna and Flora
Geese
Each winter, around 38,000 barnacle geese fly approximately 2,000 miles from Svalbard, a group of Norwegian islands high in the Arctic, to the Solway Firth. A significant proportion of these, feed on the merse and roost on the mud and sandbanks of the reserve. They make up nearly 50% of the UK’s winter population of barnacle geese. The Greenland population of barnacle geese winter on the Orkney Islands, the Hebrides and western Ireland.
The geese arrive at the reserve in small groups from late September, Barnacle geese with the majority arriving in October and early November. They return to breed on Spitsbergen, the largest island in the Svalbard group, in April and early May.
Graph showing winter population estimates for Svalbard Barnacle Goose, 2003/04 – 2014/153
3 Data provided as part of The Solway Barnacle Goose Management Scheme (SNH commissioned report on “The distribution of barnacle geese around the North Solway shore” unpublished).
3 The Story of Caerlaverock National Nature Reserve
Caerlaverock is also one of the most important sites in the Solway Firth for the pink- footed goose. Numbers peak in the autumn and spring, when there can be up to 35,000 birds roosting on the Solway. This is approximately 9% of the British population of pink-footed geese. Although many geese move south from the estuary during the winter months, several thousand remain to roost on the mudflats within the reserve and to graze on the neighbouring arable fields. Winter numbers average around 16,000, around 4 % of the wintering population.
Other wildfowl and waders
The Solway Firth is an internationally important wintering ground for nearly 140,000 wildfowl and waders, many of which make Caerlaverock their winter home. It is also a key staging post for migratory wildfowl and waders on their way to and from wintering grounds elsewhere in Britain, Europe and Africa. For this reason, bird numbers peak in early spring and late autumn. Nineteen species of waders and wildfowl spend all or part of their winter on the reserve. Internationally significant numbers of pintail, oystercatchers and knot occur on the reserve. Teal, goldeneye, dunlin, grey plover and golden plover also come to the Solway in nationally important numbers, contributing to a tumultuous orchestra of different birds when fortnightly spring tides drive the flocks off the mudflats and up onto the merse.
Table showing the numbers of wintering birds on the reserve and wider Upper Solway flats and marshes.
Upper Solway flats and marshes Numbers on NNR4 Bird species No of birds % GB population Bar-tailed godwit 2367 4.5 11 Curlew 5811 1.7* 3704 Dunlin 14566 2.7 5120 Golden plover 6121 2.4 Goldeneye 190 1.1 Grey plover 1036 2.4 109 Greylag goose 95 Knot 12271 3.6* 3036 Lapwing 615 Mallard 210 Oystercatcher 34694 4* 8807 Pintail 3900 3.8* 5648 Redshank 3088 1.7 356 Ringed plover 16 Sanderling 212 0.9 Scaup 1544 0.5 5227 Shelduck 2196 3 1660 Teal 1248 0.9 Whooper swan 117 2
* % of world population
4 Figures are 5-year average of WeBS counts on NNR
4 The Story of Caerlaverock National Nature Reserve
Breeding birds
In terms of the sheer numbers of birds, the summer is a quieter time of year. Between 45 and 50 species of bird breed here, these include 11 UK Biodiversity Action Plan (UKBAP) and 6 Local Biodiversity Action Plan (LBAP) species. Shelduck and some of the waders such as, redshank, curlew and oystercatcher make Caerlaverock their summer home too, breeding in small numbers. Birds not found here during the winter also make the most of the varied habitats found on the reserve. Tree sparrow, reed bunting and linnet, all UKBAP species, breed on the reserve, feeding on seeds of grasses and saltmarsh flowers in the merse.
Skylark Caerlaverock means ‘Castle of the Lark’, and fittingly, good populations of skylark both breed and winter on the reserve. Having spent winter further south, a number of warbler species also breed on the reserve and fill the reed beds with their songs, including sedge warbler, grasshopper warbler, reed warbler, and lesser whitethroat.
Other birds
In late summer large flocks of common, black headed and herring gulls, sometimes up to 10,000, use the land at the mouth of the Lochar Water to roost, filling the air with their raucous calls. Birds of prey such as hen harrier, marsh harrier, peregrine falcon, short-eared owl and merlin quarter the reserve, keeping an eye out for unsuspecting prey. In the last few years locally breeding ospreys are regularly seen hunting over the mudflats. The reed beds are home to water rails and also provide the prefect roost for flocks of sand martins and swallows and pied wagtails in late summer and autumn and for starlings in winter.
Natterjack toad
Caerlaverock is home to a population of natterjack toads. Here at their most northerly location in the UK, they can be found in the shallow pools at the landward edge of the reserve. Despite being relatively common on the continent, natterjack toads are Britain’s rarest amphibian. The reserve and surrounding areas may support as much as 10% of the UK’s breeding population and is therefore of national importance. Natterjack toad
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The shallow pools at Caerlaverock are perfect for the toads. Drying out in the summer coupled with the occasional inundation of saltwater, helps to prevent predators such as, fish and aquatic invertebrates from colonising the pools and eating the eggs and tadpoles. During the breeding season, these pools become the courting grounds for male toads. The chorus of calling males can, on calm spring and summer evenings, be heard up to 2km away. The toads also require short grassy areas or bare soil, sand or shingle on which to feed. During the day they burrow in the sandy soils of the reserve to avoid predators. Over winter they hibernate, again burrowing deep down into the sandy soils.
Fish
Sea lamprey and river lamprey both occur in the river channels that dissect the reserve, particularly the River Nith and the main channel of the Solway Estuary. Like salmon, both species spawn in freshwater but complete their life cycle at sea. The Solway Firth provides a migratory passage for both sea and river lamprey to and from their spawning and nursery grounds.
Sea lampreys are widespread throughout coastal Europe and eastern America. They are reasonably widespread in UK rivers although their numbers have declined in some parts of its range and becoming extinct in a number of rivers. At Caerlaverock sea lamprey are almost at their northern limit of distribution. River lamprey only occurs in Western Europe, where it has a wide distribution from southern Norway to the western Mediterranean. The UK has strong populations which are considered important for the conservation of the species at an EU level.
Invertebrates
The reserve is home to a large number of flies and other invertebrates, many of which specialise in the saltmarsh habitat. At least thirty-four species of flies are known to occur on the reserve, including a small coastal, hairy-winged cranefly that can tolerate the brackish conditions in marshes and along ditches. There are also many species of beetles, spiders, bugs, wasps, moths and butterflies.
The freshwater pools of the merse support the very rare tadpole shrimp. We recorded this species on the reserve for the first time in 2004, in pools on the merse. It appeared again in 2008. Previous records for the Solway are scarce and are only from locations further west near the Southwick Water. The tadpole shrimp has a very rapid life-cycle, maturing from egg to adult in two or three weeks after wetting. This means that it can breed successfully in seasonal ponds such as those at Caerlaverock. Like the natterjack toad, it needs pools that will dry out in summer to kill potential predators, but can survive as a dormant egg stage for several years.
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Flora
We have recorded just under 250 species of flowering plants on the reserve. Many of these such as, glasswort, sea blight and thrift are specifically adapted to the salty environment that they live in.
Where the land is less frequently inundated by the tide a wide range of grasses, rushes and sedges thrive. One of the most interesting grasses to occur here is the nationally scarce Red Data Book (RDB) species, holy grass which is also a UKBAP species. One of the first grasses to flower in spring, it is Thrift intensely aromatic. In the past it was used to strew the floors of churches, hence its name. Holy grass is only found at 5 locations in Dumfries and Galloway, representing at least a third of the known locations in the UK.
Summary
Caerlaverock’s huge expanse of mudflats and merse are renowned as some of the UK’s most important habitats for wildfowl and wader assemblages, with the wintering population of barnacle geese being one of the reserve’s defining species. The reserve also boasts hidden gems, with its shallow pools providing some of the last remaining Scottish habitat for natterjack toads and the rare tadpole shrimp.
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3 Management of Caerlaverock before it became a NNR
History of Caerlaverock
>10,000 years The low-lying land, mudflats and sandbanks of Caerlaverock ago start to develop. The first castle and a harbour is built at Caerlaverock but soon 1220 abandoned, because of the instability of its foundations on the merse. The present castle was built further back from the shore. The 1270 coastline has since receded, leaving the castle some distance from the sea. The area around Saltcot Hill is believed to be the location of Medieval period medieval salt workings. After centuries of war, during which the castle was repeatedly damaged by attacks and repaired, the estate’s owners, the 1640 Maxwell family, finally conceded defeat, and the castle was partially dismantled. Landowners began reclaiming the land around what is now the NNR for agriculture, building floodbanks and digging drainage c1800 ditches. One such floodbank can be found at the north of the reserve. A wall along the west bank of the River Nith is constructed to prevent flooding of neighbouring land. This may have c1850 onwards accelerated the process of merse formation. Maps as late as 1850 show the coastline in close proximity to Castle Woods. By 1920, around 600ha of merse had accumulated. 1864 A railway viaduct linking Bowness to Annan was constructed. Caerlaverock’s mudflats and merse were used as an Army firing 1939 – 1945 range. Caerlaverock Castle passed into the care of the nation. It is now 1946 managed by Scottish Historic Environment (formerly Historic Scotland). 1957 Caerlaverock was declared a NNR.
Land use history
Fishing
The rivers, mudflats and merse around Caerlaverock have provided a living for local people for centuries. Haaf 5 net fishing has been carried out since Viking times, 1,200 years ago, and continues today on many of the rivers leading into the estuary, including the River Nith. Other historical fishing techniques include whammeling, cobble fishing and stake netting.
5 Haaf – Norse for ‘channel’
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In the 1890s, the River Nith was ‘teeming with salmon’ (Stoba, 1975) and every farm and householder had a salmon net fixed to the foreshore. These were eventually banned on the lower Nith as they started to affect the fisheries further upstream.
The mudflats also provided a bounty. At low tide, local people would take their horses and carts out onto the mudflats to harvest cockles for the local markets. Cockles are still a valuable shellfish and commercial fishing, whether by vessel or hand gatherer, is regulated. Individuals can however still gather cockles for their own use.
Wildfowling
Local people are likely to have taken wildfowl for the pot for hundreds of years. Wildfowling as a sport and a profession however, only came into its own at Caerlaverock in the first half of the 20th century. During this time, local people also went out on a regular basis to take large bags of geese, ducks and shore birds for the city markets. By the late 1940’s, numbers of barnacle geese had dropped to less Punt gun than 1,000 birds on the Solway Estuary.
Natural forces have largely dictated land use at Caerlaverock. There were some attempts at land reclamation in the early 1800s, but these were never very successful, because of the huge tidal range in the estuary. Fishing and wildfowling, rather than agriculture, has dominated the pattern of land and resource use at Caerlaverock.
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4 Management of Caerlaverock NNR
Key events in the history of Caerlaverock since it became a NNR are as follows:
1957 600 ha. of Caerlaverock is declared a NNR. 1962 The reserve is extended to include Blackshaw Bank which provides roosting and feeding habitat for wildfowl. 1970 The Wildfowl Trust (now the Wildfowl and Wetlands Trust (WWT)) open a visitor centre at Eastpark Farm, on land adjacent to the NNR. 1971 Natterjack toad population monitoring begins. 1977 The reserve is extended to include 32 ha. of the Flooders.
1981 Late summer grazing is introduced around 2 ponds on the reserve to maintain a short turf for foraging toads. A water pipe is also installed to top up the ponds in dry summers, and proves effective. 1980 The Nith Estuary is designated a National Scenic Area. 1988 Several small geological and biological SSSIs are amalgamated to form the Upper Solway Flats and Marshes SSSI. 1992 Caerlaverock is declared a Wetland of International Importance under the Ramsar Convention and also classified a Special Protection Area. 1992 The reserve is extended to include an additional 2,205 ha. of foreshore at Priestside Bank, a main barnacle goose roost area. 1995 The Barnacle Goose Management Scheme and Solway Merse Management Scheme are launched. 1998 An Integrated Management Strategy is established for the whole of the Solway Firth candidate Special Area of Conservation. 2005 Solway Firth SAC is designated.
2006 The reserve is re-declared in line with revised ownership and to accommodate new byelaws to manage wildfowling and vehicle access.
The extended reserve now covers 8,184 ha. 2013 The NNR office is closed and sold and staff are now based in the Dumfries SNH office
Management of the Natural Heritage
When Caerlaverock was first declared a NNR, the numbers of the wildfowl, particularly barnacle geese had been dramatically reduced. It was this reduction that had prompted the Duke of Norfolk to pursue NNR status. The aspiration at the time was to provide protection for the wildlife in a way that would also allow traditional land uses to continue. Our predecessors, the Nature Conservancy Council (NCC) and the Duke worked with the Crown Estate Commissioners, the Wildfowlers Association of Great Britain and Ireland (now the British Association for Shooting and Conservation, BASC), local wildfowlers and conservationists to draw up a unique plan to integrate nature conservation, wildfowling, fishing and agriculture.
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The reserve was divided and a 292 ha sanctuary for wildlife on the merse, where no shooting or public access was allowed was established. The whole of Blackshaw Bank was also made a no-shooting area and its landward edge was the focus for public access to the reserve. The Duke retained some shooting over a small area of the reserve for occasional use when guests were in residence at Lantonside House. Controlled wildfowling was permitted on an area of merse stretching from Bowhouse to Hollands and small sections of the merse at Lantonside and Bowhouse. As was the case with many NNRs in the early days, byelaws were drawn up to assist with the management of the reserve. Amongst other things, byelaws limited shooting on the foreshore, and allowed the NCC to manage the number of wildfowling permits issued and where shooting could be carried out. This situation, with some modifications in light of changes in legislation, has successfully continued until the present day, although revised byelaws are now quite specific and seen as a last resort rather than a first approach.
Habitats
The majority of Caerlaverock NNR is made up of mudflats and sandbanks, and is managed by the ever-changing currents and tides of the Solway Firth. As a result, our natural heritage management of Caerlaverock NNR concentrates on the three areas that we can have some control over. We play an active role in keeping the merse flora short enough for the geese to feed on; ensuring that there are shallow pools for the natterjack toads to breed in; and ensuring the needs of the wildlife across the whole reserve can exist in harmony with the interests of farming, fishing and wildfowling.
Goose habitat management
Barnacle geese and other wildfowl are fussy eaters – if the sward on the merse is too long they have difficulty feeding. So, we use cattle to graze the merse and control the height of sward. This is done in partnership with local farmers. In 1995, we initiated the Solway Merse Management Scheme, in recent years this has been replaced by the Scottish Rural Development Programme and most recently the Agri- Environment Climate Scheme. Under the scheme local farmers are given an annual payment to graze their cattle following a set grazing regime. Grazing levels on the reserve are controlled to give variations in sward height and diversity. Cattle are grazed on the reserve during late summer in preparation for the arrival of over-wintering wildfowl and waders.
Many farmers recognise the benefits of cattle grazing the merse, believing that the Cattle grazing the merse minerals deposited by the tides
11 The Story of Caerlaverock National Nature Reserve are good for the cattle. The scheme has been remarkably successful, now extending beyond the reserve boundary. It has a 97% uptake by farmers in eligible areas, and is proving equally successful for the plants, geese and other wintering wildfowl and waders of the reserve.
Also in 1995, the Barnacle Goose Management Scheme (BGMS) for land outside the reserve that geese use for feeding was launched. On fields habitually used by geese, farmers are offered payments towards the maintenance of disturbance-free feeding areas on their land, and towards the scaring of geese from other parts of the farm where their grazing would be detrimental to farmers’ crops. The scheme has helped to reduce the potential conflict between barnacle geese and the agricultural interests in the area. Beyond the goose scheme area, our staff help to reduce conflicts between geese and whooper swans through advice.
Natterjack toad habitat management
The cattle also play an important role in maintaining the natterjack toad habitat. After the toad’s breeding season has ended, the cattle are allowed to graze around the edges of the pools. This helps to keep the grass short, which the toads require for foraging and prevents excessive plant growth smothering the shallow pools. During the breeding season however, we need to keep the cattle away from the pools to prevent them poaching the edges and unavoidably trampling on the toads and emerging toadlets. We have erected fencing around most of the pools to keep the cattle off during this sensitive period.
The pools can also be susceptible to drying out during periods of dry weather, which can be disastrous for the toads. In the 1970’s, reserve staff laid a water pipe to Saltcot. This allows us to keep the pools topped up with water in particularly dry weather and helps prevent loss of toads during the breeding season.
Drainage pipes have also been installed so the ponds can be maintained at a depth that best suits the toads. We have created new pools in an attempt to provide more habitat for the toads. The pools need to be shallow, open and unshaded, and close to short turf Excavation of new breeding pool foraging areas and sandy soils, where the for natterjack toads toads can burrow for hibernation and refuge. Beyond the boundary of the reserve other landowners are also being encouraged to create pools for toads through grant aid, merse management schemes, agreements and practical advice. Unfortunately evidence of natterjack toads has declined in recent years. A number of factors may have contributed to this including climate change and the chytrid virus which is believed to have wiped out amphibian populations in some areas of Australia.
12 The Story of Caerlaverock National Nature Reserve
Sustainable resource management
When Caerlaverock NNR was established it was unusual in that the aim of the reserve was to continue to allow wildfowling, along with fishing, farming and conservation. This surprising combination of priorities has proved successful because of the care and thought that went into the original permit system for wildfowlers, and because it is recognised that sustainable management of wildfowling can be compatible with the aims of the reserve.
Scottish Natural Heritage manages the permit system; chairing the management group and administrating the permit system. A contract is let to Caerlaverock Estate to monitor the scheme on our behalf. They are responsible for ensuring wildfowlers are acting responsibly and within the conditions of the permit scheme. This also helps to build up good relationships with the wildfowlers, who themselves are often an excellent source of information about the movements and behaviour of the birds and other wildlife on the reserve.
Cockle picking by hand in a sustainable manner has gone on in the Solway Firth for centuries. But in 1987 commercial cockle fishing began. Using tractors and suction vessels, landings increased from nearly zero in 1986 to 4,500 tonnes in 1991. The fishery was Wildfowler and his completely unrestricted and as a result cockle stocks dog plummeted. Boat dredging was banned in 1992 and tractor dredging in 1994. Even so, gangs of hand pickers came out onto the mudflats, continuing to deplete cockle stocks, until this too was banned in 2002.
Smaller scale managed fisheries were opened under a Regulating Order in 2006 following detailed stock assessments and modelling of impacts on birds dependent on cockles, notably oystercatcher and knot. A trial Territorial Users Rights Fishery (TURF) was opened for a 3 month period in 2013. Future cockle fisheries will be dependent upon the stock totals, availability of harvestable sizes and compliance with the requirements to protect the habitats and birds for which the site is classified as a Natura site.
Biodiversity and monitoring
Species monitoring is an important part of our work at Caerlaverock. Reserve staff carry out regular counts of the barnacle geese on the reserve. We also record the numbers and species of different wader and wildfowl during the winter as part of national counts for waterfowl. Other key species such as skylark, breeding waders and natterjack toads are also monitored. The distribution and extent of holy grass on the merse is also assessed. All of these various types of monitoring allow us to assess the effectiveness of our merse management, the barnacle goose management schemes and the wildfowling permit system. Records are fed into
13 The Story of Caerlaverock National Nature Reserve national schemes such as the Wetland Bird Survey coordinated by the British Trust for Ornithology and the Beached Bird Survey collated by the International Centre for Climate Governance (IGGC).
In addition to this, we also carry out Site Condition Monitoring to ensure that the internationally and nationally important species and habitats are in favourable condition and that our management is appropriate. In most cases recent monitoring has shown that species numbers and habitats are being favourably maintained across the reserve. Some species, notably bar-tailed godwit, are in decline on a world population basis due to factors outwith the reserve.
The merse and grassland are crucial to the birds for feeding, roosting and for some species, breeding. However in spring and summer some nesting wildfowl, shelduck for example and other birds such as redshank and skylark also need cover. Areas of gorse, willow and hawthorn scrub are maintained on the reserve to provide nesting habitat and shelter for these birds.
Research
Research on Barnacle goose led by WWT Wetland Centre at East Park is still ongoing remaining one of the longest running and most extensive bird studies in the UK.
The Solway has attracted considerable interest from geomorphologists. Smith et al. (2003) have been able to establish the changes in sea level since the last Ice Age based on mapping and dating of buried sediments in the lower Nith valley and estuary. There has also been work on the effect of storm events on the accretion and erosion of the saltmarsh Barnacle goose with GPS tagger showing that on the Solway Firth, the medieval period was one of significant coastal change and that the present estuarine sediment fills are now much more extensive (Tipping, 2007). There has also been a study of saltmarsh sediments at Caerlaverock (Hansom, 2003).
Other research has included studies of the effects of tractor and suction dredging on the cockle population and the habitats and birds dependent on the inter-tidal areas (Shepherd, et al, 1994); the effects of wildfowling and disturbance on the wader and wildfowl populations (Bell & Fox, 1991) and, the effects of habitat management through grazing for wintering waterfowl, breeding waders and natterjack toads (Scott & Hodson, 1989).
Management for People
Access to the reserve is now satisfactory. When the reserve was declared, visitors were restricted to the Blackshaw Bank area of the reserve and byelaws prevented
14 The Story of Caerlaverock National Nature Reserve activities such as the use of bicycles and boats. At the time these were considered necessary to prevent disturbance to wildlife. The original reserve byelaws have now been revised and today, visitors are welcome to explore the whole of the reserve. Of course, the wildlife of the reserve can still be susceptible to disturbance, so the focus for our management now is raising awareness and ensuring that visitors access the reserve responsibly in accordance with the Scottish Outdoor Access Code (SOAC). There are however, a few activities that we consider will cause considerable disturbance to the interests of the reserve unless they are specifically controlled.
Visitors
Most visitors that come to experience Caerlaverock look over it from the WWT visitor centre and hides at Eastpark Farm, to the north east of the reserve. It is difficult to give accurate figures for visitor numbers to the reserve itself. We have visitor counters at key access points on the reserve, but these are not always reliable and do not take into consideration repeat visitors, or those visitors who only stop to look at the wildlife from their vehicles. We estimate that perhaps as many as 30,000 visitors will stop to appreciate Caerlaverock NNR in some way each year.
We carried out a baseline survey of visitors to the reserve in the past. This gave an indication of the main types of visitor to the reserve and what it is that they enjoy about Caerlaverock. The survey shows that most visitors are older people, rather than families with young children. They enjoy venturing out onto the merse to experience the sense of space and wildness at Caerlaverock. Visitors also particularly like the peace and quiet it offers, and are most likely to come in the depths of winter to see the geese and other wildlife, or in the high summer months when the merse is in full flower.
Visitor facilities
Our approach on Caerlaverock is to provide visitor facilities and opportunities which offer a “wilderness” experience on the NNR and supplement the ones provided at East Park and Caerlaverock Castle.
There are car parks for the reserve at Hollands Lane and Castle Corner and one between Castle Corner and Kenneth Bank. Public parking is also available at Powfoot, Brow Well and Carsethorn.
The track from the Castle Corner car park through Castle Woods is an easy access path. This leads to Caerlaverock estate’s shelter and information point, which although not on the reserve, offers a readily accessible opportunity to get closer to the merse and look out over the reserve. From here, the path continues on the merse across the front of the Flooders to join a circular walk around the Flooders itself. This circular path can also be accessed from the car park at Hollands Lane. A bird hide on the ‘Reedbed Ramble’ at Flooders provides a sheltered point for viewing the merse.
On the west side of the NNR you can access the reserve at Burnfoot or from the Scottish Wildlife Trust Drummains reedbed reserve, near Kirkbean.
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We have interpretation boards at both the Castle Corner and Hollands Lane car parks to help visitors find their way round and to give them information about the reserve and its wildlife. At the car parks there are also notice boards that we keep updated with news of forthcoming events.
Events and promotion
Reserve staff offer a range of events on the reserve aimed at all ages and interests, and vary with the seasons. In winter, the focus is on the geese and other wintering birds, as well as the spectacular high tides that flood the reserve. During summer the ponds, flowers, and our management work provide fascinating subjects to tempt visitors out onto the merse.
There is a reserve leaflet available at the car parks, visitor room and tourism outlets. Or it can be downloaded from Scotland’s NNRs website: www.snh.org.uk/nnr- scotland. Updates on what’s happening on the reserve appear on the NNR website and through social media.
Local community
There have always been close links between the reserve and the community at Caerlaverock through close working relationships with the fishing, wildfowling and farming communities. Some local people are now working with SNH as volunteers for the reserve providing invaluable time and support for reserve staff. Their main task is to support the staff in monitoring the reserve’s wildlife, habitats and carrying out repairs and maintenance to the access facilities and other tasks and, to keep an eye on activities on the reserve.
Property Management
SNH don’t own land on Caerlaverock but manage the NNR either through leases or nature reserve agreements with four different owners.
We lease a workshop and store near Glencaple, for reserve maintenance and equipment storage.
We are responsible for the maintenance of paths and some of the fences on the reserve. This work is either carried out by reserve staff or contracted out as necessary. We lease and maintain the car parks at Castle Corner and Hollands Lane from Caerlaverock Estate.
16 The Story of Caerlaverock National Nature Reserve
Map showing tenure at Caerlaverock NNR
Summary
Although we do not own any of the reserve, the close working relationship established between Caerlaverock Estate and the Nature Conservancy Council in 1957 built a solid foundation for the successful management of the reserve. This partnership approach continues today and the remarkable increase in the barnacle goose population since the reserve’s declaration is testimony to this achievement.
The aim for the future will be to ensure that the balance we have achieved a balance between wildlife protection and the sustainable use of Caerlaverock’s rich resources can continue.
17 The Story of Caerlaverock National Nature Reserve
5 Document properties
References
Bell, D.V. Fox, P.J.A. Wildfowl and Wetlands Trust (WWT) British Association for Shooting and Conservation (BASC) 1991. Shooting disturbance: an assessment of its impact and effects on overwintering waterfowl populations and their distribution in the United Kingdom (1991) Nature Conservancy Council (NCC). CSD Report (1242)
Hansom, J.D. 2003. Solway Firth (North Shore), Dumfries and Galloway. In: May, V.J. & Hansom, J.D., Coastal Geomorphology of Great Britain. Geological Conservation Review Series, 28. Joint Nature Conservation Committee, Peterborough, 541-548.
Musgrove, A.J., G.E. Austin, R.D. Hearn, C.A. Holt, D.A. Stroud & S.R. Wotton. 2011. Overwinter population estimates of British waterbirds. British Birds 104: 364-397.
Scott, R.Hodson, L.M.Institute of Terrestrial Ecology (ITE) 1989. Preliminary review of management practices on the saltmarshes of north-west England Nature Conservancy Council (NCC). CSD Report (935)
Shepherd, M.; Clark, N.A.; British Trust for Ornithology (BTO); Scottish Natural Heritage (SNH) 1994. The effect of commercial cockling on the numbers of wintering waterfowl on the Solway Estuary.
Smith, D.E., Haggart, B.A., Cullingford, R.A., Tipping, R.M., Wells, J.M., Mighall, T.M. & Dawson, S. 2003. Holocene relative sea-level change in the lower Nith valley and estuary. Scottish Journal of Geology, 39, 97-120.
Tipping, R. 2007. Structure, composition and significance of Medieval storm beach ridges at Caerlaverock. Dumfries and Galloway Scottish Journal of Geology, 43, 2, 115-123(9)
Photography
Photography by Nick Gedge, Alan Steel, Annelise Clebant and Lorne Gill (Scottish Natural Heritage).
Acknowledgements
The Story of Caerlaverock National Nature Reserve (1st edition) was been written by Sue Walker (Freelance contractor) and Emma Philip (Managed Sites Officer – National Nature Reserves) and approved by Chris Miles (Area Manager - Dumfries and Galloway).
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The 2nd edition has been updated by Francois Chazel (Reserve Manager) and edited by Susan Luurtsema (Operations Officer – National Nature Reserves), and approved by Jonathan Warren (Area Officer – Dumfries and Galloway).
We would like to thank the following SNH staff for their contribution and comments on the 1st edition: Jonathan Warren (Area Officer - Dumfries and Galloway), Alan Steel (Reserve Manager), Nick Gedge (Area Officer), Rachel Wignall (Policy and Advice Officer – Earth Science), John Gordon (Policy and Advice Manager - Earth Science), Nigel Smith (Policy and Advice Manager - Natura) and Susi Hodgson (Corporate Services Officer).
Links
Scottish Natural Heritage www.snh.org.uk SNH Sitelink www.snh.org.uk/snhi/
Wildfowl and Wetlands Trust www.wwt.org.uk
Historic Environment Scotland www.historic-scotland.gov.uk
Dumfries and Galloway Council www.dumgal.gov.uk
Joint Nature Conservation Committee www.jncc.gov.uk
British Association for Shooting and Conservation www.basc.org.uk
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