Raet Protected Landscape kommune, Aust- Raet Protected Landscape There are three main criteria that form the Five methods for the protection of the area: basis for the protection of Raet Protected Raet (1) Protected Landscape, including Landscape. the flora and fauna, was protected by Royal Decree on 15 December 2000. The pro- These are: tected area stretches from, and includes, • sediments Jerkholmen in the west to Tromlingene in • geomorphology the east – a distance of about 15 kms. The • fresh water dammed up by the moraine protected area covers about 5,400 acres, of which about 4,600 acres is sea. The many bare outcrops of rock shaped by glacial erosion that we find in the area are The aim of the protection is «to preserve the examples of geomorphological shapes. specific character of the natural landscape These are bedrock bumps that have been and the cultivated land with geological ground smooth and fine on the stoss faces occurrences from the Quaternary period towards the ice and torn up on the lee faces. and distinctive animal and plant life linked with Raet in the coastal area of Aust-Agder».

Front page photo from Bjellandsskjær, Tromøy. Photo: Ove Hetland

Tromlingene

Tromøysund Alvekilen

Arendal Tromøya Bjelland

Galtesund

Spornes

Hisøya Hove Gjesøya

Merdø Havsøya

Gjervolds Ærøya øya Lille Torungen

Halvors holmene Store Torungen Jerkholmen

2 Within the area there are three (2) nature final spasms of the Ice Age. Probably the reserves which is a «stricter» form of pro- glacial front of the inland ice towered like a tection than protected landscapes. These steep wall in the sea, with proportions that are not included in the protected landscape are similar to those we find along the coasts but act as «islands» in the protected lands- of Antarctica and Greenland today. The ra cape area. These three nature reserves are, moraine stretches from Finland, through from west to east, Indre Halvorsholmen, Sweden, Østfold county in and Store Torungen and the western part of crosses the Oslofjord at Moss. In Tromlingene. The first two are intended to county it comes to the surface at and take care of nesting seabirds and therefore provides the fertile soil for the country’s no one is permitted to go ashore from 15 largest beech forest Fagus sylvatica at April to 15 July. The western part of , amongst other things. After that it Tromlingene is protected to preserve the disappears into the sea again at Mølen, but wetlands. The eastern part of Tromlingene appears here and there as islands like has so-called bird-life protection as a part of Stråholmen and Jomfruland in the county the protection regulations in Raet protected of . In Aust-Agder county we first landscape. notice it in the east, just off Flosta, where the cobblestone island of Målen appears. After On the outer edge of Tromøya the (3) forest that we see the islands called Tromlingene, was protected by a Forest Act as early as and it is here that Raet Protected 1914, the purpose of this was to create Landscape begins. We can clearly see the shelter for the areas within. The forest is still large amounts of boulders and cobbles- protected, but it no longer has the same tones that the sea has washed out from function as it had previously since large the moraine material at Spornes outside parts of Tromøya now have considerably Tromøy, on the outer side of Merdø and more vegetation. further west in the protected area on Jerkholmen, and on Målen. From here it Within Raet Protected Landscape the appears on land at Hasseltangen, where following areas have been set aside for (4) again it is covered in beech forest, and can outdoor recreational activities: from west then be traced up to Feviktoppen, , to east – Jerkholmen, Skjelbergholmen, Birkenes and then onwards in a westerly Flatskjær, Tvisteinen, Ærøya, parts of direction. Raet, and similar end moraines in Havsøya, parts of Merdø, Hove and neighbouring countries, clearly illustrate the Spornes. Areas set aside for outdoor distribution of the inland ice at an important recreational activities are either owned by period when the ice surface was melting the government, the municipality or there during the last Ice Age. are agreements between the government and private landowners, such as the (5) The moraine in the protected landscape was Coastal Park («Skjærgårdsparken»). deposited entirely underwater. After the ice withdrew, the sea swamped low-lying land areas. Following that the glacio-isostatic End moraine Raet uplift of the land gradually took place. The Raet – which is the name of the largest highest level of the sea after the last Ice Age continuous end moraine in Scandinavia – is known as the marine border and in the is an end moraine after the last Ice Age, and Arendal area it reaches up to 65-70 metres is one of the criteria for the protection of the above the present sea level. Tromlingene area. Raet moraine is an enormous gravel islands were raised above sea level 3-4,000 ridge that was deposited by advancing years ago, and Jerkholmen somewhat later. inland ice 10-11,000 years ago in one of the

3 Topography, Geology and Sediments The visible topography in the protected landscape area is relatively flat. Islands like Tromlingene (14 m above sea level), Jerkholmen (9 m above sea level) and The Allerød period 11-12,000 years ago. The inland ice Målen (about 2 m above sea level) consist has receded and the border of the ice lies further in than the present-day coastline. The glacier has deposited mainly of sediments. However, if we dip scattered moraine deposits on the sea bottom, and in down beneath the surface of the sea, the this period silt and clay from the sea are also deposited. picture is rather different. There we see the Sand and stones are dropped from passing icebergs. highest ”mountains” of underwater reefs, sunken rocks and islands, whilst the largest ”valleys” form dark depths. Between Jerkholmen and Store Torungen we find some depths of 157 metres. Between Havsøya and Merdø there is also a distinct deep ”valley” that continues in Galtesund. In the Younger Dryas period between 11-10,600 before the present time, the front of the glacier advances to the Raet Protected Landscape consists pre- Ra-line. Sediments on the sea bottom are pushed together and deposited, together with moraine materials dominantly of bedrock although there are that the ice carries with it, as an end moraine (Ra-mor- local occurrences of diabase dikes. enen). The sea level is about 61 metres higher than today. Large amounts of sediments have been deposited. On the side facing the sea, waves have washed out the small particles over a very long period and therefore we find the coarsest material like cobblestone and large stone boulders on the surface. The advance and retreat of the front of the glacier has Under the upper ”erosion skin” we find fine created smaller ridges parallell to the Ra-line. In post- particles like sand, silt and clay that are only glacial time, following the glacio-isostatic uplift of the a metre or two beneath the surface. Also in land, the moraine was subject to erosion by the waves. the surf zones you can see a number of Surface material is sorted and moved around. Stones and blocks are washed out and cobblestone areas are well-developed beach ridges of gravel and formed. stone that today cover large areas of the moraine in this area. After several thousand years of vegetation that has deposited leaves, needles etc, a thin layer of humous has formed on the surface. In the lower-lying parts, damp and swampy areas have been formed. In addition to Botnetjern on Tromøy, we can find smaller occurrences of open Today, the Ra moraine, which largely consists of silt and moraine material containing clay (moraine clay), has a freshwater on several of the smaller islands. layer of beach-washed material, partly with large blocks and cobblestones on the surface. Sandy marine beach deposits have settled over the fine grained sea deposits on both sides of the Ra. The characteristic glacially- Climate and vegetation shaped smooth whale-back rocks on the outside of the Raet Protected Landscape lies far south in Ra form an effective barrier against continued erosion of Norway and entirely in the beach area, part- the sediments. ly under the sea and partly on land. The climate is typically governed by the ocean. Formation of the Ra. Illustr.: Ivar Johan Jansen Throughout the protected landscape area

4 seaspray is driven in by the strong wind. achieved by having a certain amount of The proximity to the sea and the area’s weight placed in the bottom of the boat as relatively flat topography mean that it is oft- ballast. Earth and other deposits were used en windy. There is seldom much snow in the for this purpose and in this way foreign area. The sea modifies the temperature plants and seeds were imported – known throughout the year so that the winters are as ballast plants. Raet Protected Landscape relatively mild and summers are cool, even has several species that have been though Sørlandet is the district in Norway imported like this. that has the most sunny days during the year. Of the many botanical curiosities to be found we would mention the following: On Because Raet Protected Landscape lies so Merdø there is a large holly tree Ilex aqui- far south, you can find species that normally folium growing in the thicket. This is further belong to more southerly latitudes, and that east than we usually find this species. On therefore have their northernmost boundary Tromlingene there is a large, round yew on the coast of Sørlandet. bush Taxus baccata. It stands in the midst of the cobblestones and neither looks like a When sailing ships previously travelled yew nor grows at a place you would expect between the coast of Sørlandet and the to find this plant. Also on Tromlingene continent they needed to maintain stability interesting species like moschatel Adoxa when returning without cargo, and this was moschatellina, greater tussock-sedge Carex

Jerkholmen, or Jerken as it is known locally, is the only one of the islands in Raet Protected Landscape that exclusively consists of sediments. One can clearly see two large and several smaller burial mounds on the island, as well as two large hawthorn trees Crataegus monogyna. Photo: Ivar Johan Jansen

5 Harebells Campanula rotundifolia can be found on islands like Jerkholmen and Tromlingene, but are also present on large areas of the Protected Landscape. Photo: Ove Hetland paniculata, common meadow-rue Thalictrum was recently found on Sven Johnsen’s islets, flavum and brooklime Veronica beccabunga just east of Jerkholmen. can be found. One strange thing is the fantastic spring blossoming of thrift Armeria On Tromlingene islands there are several maritima on Tromlingene. Both on Lille plants that attract special species of butter- Torungen and at Merdø one can see flies, and there are several southerly species masses of beautiful, yellow, wild tulips that otherwise do not often occur in Norway. Tulipa sylvestris flowering in the early It is particularly amongst the small butterfly spring. On Jerkholmen there are two monu- species that we find the rarest types. On mental hawthorn trees Crataegus monogyna Jerkholmen and the nearby islets many old that are very noticeable. It is rare for world swallowtail butterflies Papilio machaon hawthorn to grow into such large trees can be seen. These butterflies are probably as we find here. the largest and most beautiful butterflies we have here.

Animal life Amphibians and Reptiles Insects On the outer edges of the islands Merdø This far south in Norway with its special and Tromøya we have two locations with flora, one can also expect to find exciting smooth newts Triturus vulgaris right on the insects. A species of beetle new to Norway edge of the beach. In stormy weather they

6 are exposed to a great deal of salt water, Birds which would normally be intolerable for Tromlingene islands and Jerkholmen are the these sensitive amphibians. We also find two most important localities in the pro- the same situation at Bjelland on Tromøya tected landscape area for migratory birds. where there are several localities with OnTromlingene there are long muddy smooth newts. beaches that at low water constitute large areas, and these make Tromlingene Aust- It is not known to what extent other amphi- Agder’s best migratory bird locality for wad- bians such as frogs and toads have been ing birds – but they are also important for observed in the protected landscape. When many other species. A number of rare speci- it comes to reptiles, one can expect to find es have been observed here, like: shovelers species such as vipers Vipera berus, Anas clypeata, garganey Anas blindworm Anguis fragilis and grass snake querquedula, black-tailed godwits Limosa Natrix natrix. Also the smooth snake limosa, avocets Recurvirostra avosetta, Coronella austriaca can probably be spotted redshank Tringa erythropus, found in the area. Sandwich terns Sterna sandvicensis and even Greater flamingo Phoenicopterus ruber.

The geological occurrences from the Quaternary period are of great natural science and pedagogical value. The well- developed beach ridges and areas consisting of boulders and pebbles worn smooth by the action of the waves are particularly valuable. In the last-mentioned areas one finds rocks from almost everywhere in . The photo shows Jerkholmen. Photo: Ove Hetland

7 There are several places on Merdø and on the outer Havsøya is a holiday paradise with its small houses edge of Tromøya where smooth newts Triturus vulgaris characteristic of the south coast of Norway. can be found. Photo: Arild Pfaff Photo: Ove Hetland

Jerkholmen is situated furthest out in It is obvious that Jerkholmen is the county’s Sømskilen. Particularly in bad weather, most certain locality to see short-eared owl Sømskilen is a resting place for large Asio flammeus on autumn and spring migra- numbers of ducks, and many nest here. It tion. Merdø is also an interesting island also serves the function of a port of refuge when it comes to birds. Many uncommon for many species. Jerkholmen is the next small bird species have been observed here best locality for migratory birds in the area. and every year there are several nightin- Jerkholmen and Tromlingene islands are gales Luscinia luscinia singing at Merdø. very similar, but Jerkholmen is smaller and does not have the same qualities when it Within the protected landscape area comes to muddy beaches. Species that are there are two seabird reserves: inner typical for Jerkholmen are: linnets Carduelis Halvorsholmen and the western part of cannabina, skylarks Alauda arvensis, com- Store Torungen with the adjacent islets and mon gulls Larus canus, pipits Anthus, and skerries. Store Torungen is one of the coun- during the late summer and autumn, large ty’s best seabird reserves with big colonies flocks of young starlings Sturnus vulgaris. of the larger gulls: herring gulls Larus argentatus, great black-backs Larus marinus and lesser black-backs Larus fuscus. Also common terns Sterna hirundo have had a colony here for a number of years, and the islands are also a refuge for many eider ducks Somateria mollissima.

Inner Halvorsholmen has nowhere near so many nesting birds as Store Torungen, but also here we find the large gulls nesting. Probably this was the first nesting area for greylag geese Anser anser in recent times in Aust Agder. In 1994 they were observed The round yew tree Taxus baccata on Tromlingene here with young. Previously there was a big appears to grow right out of the cobblestones. There is probably boulder clay just beneath the rocks. colony of common terns. Photo: Ove Hetland

8 The well-known local author, Gabriel Scott, used words like "eerie, shadowy twilight, cloaked in mist, ghostly foot- steps" to describe the evening mood on Tromlingene. Photo: Arvid Johnsen

Mammals Whale and seal are two types of marine 85% of Raet Protected Landscape consists mammals that sometimes visit the area but of ocean and this limits the amount of land- no permanent occurrences are known. It is based mammals. Roe deer Capreolus primarily the common seal Phoca vitalina capreolus, hare Lepus europeaus, badgers that is the principal seal type in this area – Meles meles and mink Mustela vison are not least at Jerkholmen in Sømskilen. Pilot amongst the most common of the larger whales Globiocephala melaena are occas- species. In addition we also find varying ionally sighted, but more frequently porpois- numbers and types of small rodents on the es Phocaena communis, the small whale large, grassy islands like Tromlingene and species, are registered in the area. Jerkholmen. Bats Chiroptera can also be seen in the area and presumably there are several different species. Previously hedge- Traditional use of Raet Protected hogs Erinaceous europaeus and red foxes Landscape Canus vulpes were also seen in the district, but it is uncertain whether these species are Historical sites still here. On Jerkholmen and Tromlingene There are more than 135 occurrences sheep graze, and this contributes to limiting of historical sites, stone burial mounds, the vegetation so that the landscape is more pavements, parapets, foundations and open. excavations registered in the landscape area. These are from 1800 BC up to AD

9 on Merdø and Haysøya are particularly important. They include characteristic house types. It is worth mentioning that there are also remains of buildings and other constructions from the Second World War.

Cultural landscape The countryside along Raet Protected Landscape has been marked by human activity in the area for generations. Descriptions from Hove farm in the 1770s give us a picture of what the area looked like then. The landscape has become increasingly overgrown compared with the A few pairs of Shelduck Tadorna tadorna are to be found grazing pastures at that time. In about 1790, in the Protected Landscape. Photo: Ove Hetland Merdø was an open landscape clearly marked by human activity. The yew tree on Tromlingene, the holly on Merdø and the 1000. Of these there are 49 certain historical hawthorn on Jerkholmen tell us about a sites, and those on Jerkholmen and period when the cultivated countryside Tromlingene islands are of high priority in was used differently than it is today. a national perspective.

In the olden days it was common to bury the dead in monumental stone burial mounds at the highest point in the landscape. The dead should be positioned so they could both see and be seen, and therefore a view over the ocean was decisive when selecting the spot. It was the district’s most powerful persons who were honoured with burial in such mounds. The bodies were dressed in their finest clothes including jewellery and other possessions. Frequently the burial gifts were later stolen by grave robbers. The Honeysuckle Lonicera periclymenum is the flower for burial cists were placed directly on the rock the County of Aust-Agder. Photo: Ove Hetland in the middle of the burial mound and these were often built of flat slabs of stone. In addition to the large and easily seen burial Outdoor recreational activities mounds on Jerkholmen and Tromlingene, Ever since the early 1900s outdoor there are a number of smaller and less recreational activities have been popular in conspicuous burial mounds and barrows the Hove area. Today the entire coastal area in the protected landscape area. of Sørlandet is very popular throughout the summer months, and islands like Jerk- holmen, Tjuvholmen, Ærøya, Havsøya, Cultural heritage Merdø, Gjessøya and Tromlingene are The clusters of buildings at Brekka, Lia and particularly attractive and visited by many Bjelland on Tromøy, as well as those we find people. Seabird hunting, fishing and the

10 placement of fish traps and crab and lobster • There are several large, impressive pots are activities that increase during the cultural memorials consisting of stone autumn and early winter. Areas like Hove burial mounds in the area. These tell us and Spornes on the outside of Tromøy are about the culture and religion of our popular walking areas also during autumn ancestors. We emphasize that historical and winter. When the worst autumn storms sites and cultural memorials formed prior are raging, the view is spectacular on these to 1537 are automatically protected by extremely exposed cobblestone beaches. law. We request that these stones remain Pollen tests that have been carried out on where they are. the islands of Tromlingene indicate that grazing has pretty well taken place during • Take care not to place discardable bar the entire period there has been vegetation becues on the bare rock or grass as this on the islands. can cause permanent damage, and please remember to take discardable bar becues with you after use! Bonfires also Take care of Raet Protected Landscape cause permanent damage to the bare • Disturbance or removal of any boulders, rock or grass and must therefore be rocks or shingle from the area is pro placed in suitable areas, for example on hibited. These must not be moved for any sand, gravel or pebbles or sites that have purpose, since they are a part of Raet previously been used. Protected Landscape. They must not be moved around to create sun traps, wind • If you find birds’ nests or animals’ dens, shields, sculptures or anything else. do not pause for too long to observe these. It is best to look whilst keeping on

The entire coast of southern Norway is much used for boating activities, particularly in the summer. Raet Protected Landscape has many south coast idylls which encourage outdoor recreation. Photo: Arild Pfaff

11 the move. Lengthy stops disturb the birds The area is protected against encroach- and animals. In addition the watchful eyes ment and activities which may alter the of species that eat eggs and young birds natural conditions of the landscape. 0002 and animals – for example crows Corvus • corone, magpies Pica pica and mink - Motorized traffic in isolated areas is for- often watch our movements and inspect bidden, as is the parking of caravans. the places where we have stopped. If the

nervous behaviour of adult birds or Plant communities in the shore area, Denne informasjonen er utarbeidet i 2001 av: Arild Pfaff Biologiske Undersøkelser. animals causes you to suspect that you including the seashore and meadows, have stopped near nests or young are protected against all forms of animals, you must move on to another site. damage and destruction.

• Never throw litter in the countryside, but In the eastern part of Tromlingene the please take home with you any rubbish birds and their nests, eggs and young you might find in Raet ProtectedLandscape! are protected against all forms of destruction and unnecessary disturbance. • As a rule of thumb: Leave the area in the Hunting, trapping and the use of firearms is same condition as you found it – or better! for- bidden. Dogs must be kept on a leash.

Generally, hunting and fishing Rules for behaviour and is permitted in the Protected Landscape in accordance with management prevailing regulations.

You are welcome to visit Raet Protected The County Governor in Aust-Agder is Landscape, but bear in mind the following responsible for the management of Raet regulations, which are an extract from the Protected Landscape. protection regulations: There is frequent supervision in Raet Protected Landscape.

Fylkesmannen i Aust-Agder would like to thank Margaret Gulbrandsen for translating the brochure into English.

Additional information concerning the Fylkesmannen i Aust-Agder protected areas and the protection miljøvernavdelingen regulations can be obtained from: Serviceboks 606 NO-4809 ARENDAL Telephone: +4737 01 75 53