Coastal Adaption and Marine Exploitation of the Island Hiiumaa, Estonia, During the Stone Age with Special Emphasis on the Kõpu I Site

Published: Landscape and Life. Studies in honour of Urve Miller. PACT 50, Rixensart 1996, 197–211

This paper presents a project carried out by archaeologists and natural scientists, based on the archaeological excavations of the Early Neolithic Kõpu I site, on the Hiiumaa island in 1994. The results presented here deal with the topographical position of the site, its size and structure, seasonality, economy and the possible origin of the coastal settlers of Hiiumaa. The Kõpu I site provides one of the oldest sets of archaeological material to have been discovered on Hiiumaa. A small island in the Litorina Sea did not offer very good living possibilities for prehistoric people. This site seems to have been used by seal hunters at certain season of the year only.

The island, Hiiumaa, is one of the archaeologically less studied areas in Estonia. The better investigated antiquities of the area are stone-cist graves from the Iron Age. Up until 1981 only some stray finds from the Stone Age were known from Hiiumaa (Lõugas and Selirand, 1989).

During the excavations of the Pre-Roman stone-cist graves at the village of Kõpu in 1981, an archaeological inventory was carried out in the surrounding area. Vello Lõugas, the leader of these excavations, found a new site in the Ristipõllu farmstead, in the village of Ülendi (V. Lõugas, 1982, 1993). Already, that year, an area of 2 x 3.5 m was excavated and one fireplace with a diameter of 1.5 m was studied. A fragment of a stone axe, a flint scraper, some quartz artefacts, quartz and flint pieces, a piece of the Baltic red-quartz-porphyry and a small number of animal bone remains were found (V. Lõugas, 1982). Charcoal from the fireplace was radiocarbon dated to 5330±90 BP : TA-1493 (V. Lõugas, 1993). The absence of Neolithic ceramics from this excavation area was the main reason for the opinion at that time, that the site was used during the Late Mesolithic period.

In 1993, the question of the necessity for further investigation of the Stone Age sites on the Kõpu Peninsula, involving interdisciplinary collaboration between archaeologists, geologists and biologists, was raised. As a result new excavations were planned within the framework of a project on the Estonian Stone Age coastal habitation, geology and fauna. This is also part of the PACT palaeoenvironmental research.

The aim of these excavations was to obtain new and exact datings for the appearance of the early inhabitants of the island, to find more evidence relevant to the history of marine vertebrates and to classify more precisely stratigraphic and topographic situation of the site.

Kõpu is the largest and most westerly peninsula of the Hiiumaa island. The peninsula is approximately 20 km long from west to east, with a width ranging between 3.5 and 7.3 km (Fig. 1). Morphologically the Kõpu Peninsula can be described as a central upland surrounded by planes on the east, south and west. This upland lies at a height of 44–46 m and rises in its south-western part to 59–62 m above the present sea level. The highest point of the peninsula — Tornimägi — at 66.2 m a.s.l. is also situated here. Other areas of high altitude are the dunes located to the east and south-west of the central upland (St. Andreas Hill, 63.0 m a.s.l.).

The upper part of the central upland of Kõpu can be described as a big glacial erratic, consisting of tills, which has been transported here by the continental ice at the time of the Palivere stadial of the Weichselian glaciation (Eltermann, 1993). Later, this part of the central upland with older till beds and limnoglacial sediments of the Pandivere stadial was covered by fluvioglacial and other glaciolacustrine deposits left behind by the retreating glacier. This resulted in a ridge-like landform running from east to west with several smaller branches. The soft erodable Quaternary deposits have been partly reshaped by the waves of the ancient stages of the Baltic Sea. Thus, there is an abundance of both accumulative (beach ridges) and erosional (bluffs) coastal formations.

The Kõpu Peninsula was the first part of Hiiumaa to emerge from the sea as a small island about 10,300 years ago. Today, the highest shorelines of this island, which are related to the Baltic Ice Lake Stage, can be found between 53 and 62 m.

Kents (1939) separated the Ancylus Lake and the Litorina Sea bluffs into 10 different series and the Ancylus Lake coastal ridge into 12 series (see also Raukas and Ratas, 1995). At the time of regression, which followed the maximum of the Ancylus transgression and especially during the catastrophical lowering at the end of the Ancylus Stage — A VI (Kessel and Raukas, 1967), the land emerged from the water step by step primarily from the south, west and east of its original point of emergence (Fig. 1). A bay, later a lagoon, was formed, at what is presently known as the Kõivasoo Bog, bordered with coastal ridges of the Ancylus Lake. At the end of the Ancylus regression the water level in the Kõpu area dropped to as low as 20 m a.s.l. (Raukas and Ratas, 1995) and thus, for some time, this bay became a lake isolated from the sea.

Evidence of the Mastogloia/Litorina transgression is found earlier in Hiiumaa than in other parts of Estonia (Kessel and Raukas, 1967). As a result of the rising water level a lagoonal lake existed once again at Kõivasoo Bog (Sarv et al., 1982). During the following regressive phases of the Litorina Sea, the island of Kõpu grew remarkably in size (Fig. 1). Kents (1939) established the Litorina beach ridges and bluffs at a height of 15–27 m a.s.l. This is supported by the 1994 field work findings of a brackish water subfossil mollusc fauna (identified by E. Tavast) Cerastoderma glaucum, Hydrobia ulvae, Littorina litorea and Scrobicularia plana (at 26 m a.s.l.) in the ridge located at the Kõpu I site as well as by findings of a typical Ancylus fresh water mollusc fauna Lymnea baltica, Ancylus fluviatilis, Lymnea palustris, Pisidium amnicum and Anisus contortus (at 30 to 32 m a.s.l.) at the village of Kõpuküla. This confirms that the maximum level of the Litorina Sea was more than 26 m above the present sea level, but not as high as 30 m a.s.l.

Around 4800 BP the Kõivasoo Lake became a fen (Sarv et al., 1982). Also, at this time, the intensive formation of dunes began.

During the last 4000 years, the time of the Limnea Sea stage, the regression of the Baltic Sea has continued. The coastal formations of this time can be found at 15 metres or less above the present sea level. At the beginning of the Limnea Sea stage (Lim I–II) a connection formed between Kõpu Island and Hiiumaa.

The first plant immigrants to the island could have been spread by seed eating birds and/or by the wind. In the beginning, shrubs probably dominated the flora of the island while the spread of trees was slower.

It seems likely that by the time hunters and fishers first appeared on the island in the Late Mesolithic and/or the Early Neolithic period the flora was already quite diverse. According to Sarv et al. (1982), alder, hazel, pine and lime were the dominant species of trees at that time.

An increase in the salinity of water during the beginning of the Litorina Stage allowed an abundence of marine fauna to develop in the Baltic and consequently an increasing interest for people to inhabitat the island. The southern coast of the ancient Kõpu Island offered more favorable conditions for prehistoric seal hunters than the steeper northern coast. Therefore, there are numerous Stone Age sites on the coastal ridges of the Ancylus regression and the Litorina transgression in that region (Fig. 2).

New excavations were carried out at Kõpu I in July/ August, 1994. A 32 m long and 1 m wide trench with one extension 1 x 2 m (Fig. 2 and 3) cut the ancient coastal ridge almost at right angles. The trench was so positioned to give maximum information of the stratigraphy of the site and the range of the cultural layer at that place.

Since the area had been used as a field for quite a long time, the uppermost layer (25–30 cm) was mixed. Under the mixed layer there was an untouched cultural layer characterized by a lightly dirty (cinder) soil with distinct black fireplaces. The cultural layer started at a height of 26.5 m a.s.l., but continued to the west of the excavated trench, i.e. more than 27 m a.s.l. (see Fig. 3).

Altogether seven fireplaces have been found. All these were surrounded with stones and deepened into the natural ground level. The strongly swollen and crumbled granite stones and the dark cinder soil indicate intensive fire making. The diameter of the fireplaces was mostly 0.6–1.3 m. Only two fireplaces were represented by an oval stone pit.

About 500 fragments of pottery have been found from the site excavated in 1994. Stone rubble dominated in the temper of ceramics, i.e. it occured in the composition of 90 % of the fragments. Most of the stone rubble has been mixed with some organic matter which was burnt out, and the only evidence of usage of the latter is the porosity and lightness of the fragments. Some potsherds seem to have an organic supplement. It is not clear, however, whether the organic matter was added to the clay body or whether the clay was taken from upper layers together with roots.

The pottery was made by the coiling technique. The coils are connected to each other by the U-principle; one of the junction edges of the clay coil is convex and the other is concave (Fig. 4 : 1, 2 and 3). The clay coils are quite narrow, about 0.7–2.3 cm (86 % of the coils are less than 2 cm).

The walls of the vessels are rather thick: about 6–13 mm. Since the ceramics have been preserved only in small pieces, a reconstruction of the shape of the vessels is impossible. We can only assume that the pots had a conical shape with a pointed or rounded bottom.

The surfaces of the vessels are mostly smoothed, but about 5 % of the fragments have been striated. The striae are narrow, 1–2 mm wide. Only one fragment has a wider striae, up to 4 mm. 2.5 % of potsherds are ornamented. Mostly there are notches of approximately one millimetre on the surface, but two fragments have a grooved ornament and one has a pit with of 4 mm diametre which nearly penetrates the vessel wall.

The ceramics from the Kõpu I site are peculiar among the Early Neolithic pottery in Estonia. Some of the technological parameters indicate Narva Type ceramics, such as the occurrence of organic matter in the clay body. More characteristic is the construction technique, i.e. the U-principle which occurs frequently around the estuary of the Narva river, in east Estonia (Gurina, 1967; Kriiska, 1994). More than 2/3 of the Narva Type ceramics from this region are made by the U-technique. An essential difference between the pottery on the Estonian mainland and at Hiiumaa is the occurrence of stone rubble in the Kõpu ceramics. A mineral supplement is also characteristic of the Early Neolithic pottery found at the Kõnnu site, Saaremaa (Jaanits, 1979).

The surface finish and the ornaments of the Kõpu ceramics are quite similar to the Narva Type pottery, but the similarity with the Kõnnu ceramics is greater. Characteristic of the latter is a scarcity of ornamentation and the presence of grooves and comb impressions. A feature typical of the ceramics of Kõpu and Kõnnu is the occurrence of small pits, which nearly penetrate the walls of the vessels (Jaanits, 1984).

4349 stone bits, stone artefacts and fragments have been gathered from the Kõpu I site. 3475 of them are quartz, rarely quartzite, fragments (Fig. 4:5) or artefacts, 687 flint stone bits or artefacts, 144 stone fragments and 43 sandstone splinters (i.e. mainly small polishstone fragments).

The majority of the finds are manufacturing remains and differed in size. About 30 quartz scrapers (Fig. 4:8) are characterized by an oval point which thickens to an opposing straight edge. There are some triangular and trapezium-shaped scrapers in the material as well. Some quartz and quartzite knives (Fig. 4:10), quartz bores (Fig. 4:9) and quartz burins (Fig. 4:11) were found. Among the latter, there are two pieces which have beak-shaped points (Fig. 4:11). Similar burins are known from the Kääpa site, south-east Estonia (Jaanits, 1968).

The flint stone was white or grey and of bad quality. The flint stone is mostly in the form of fragments. There are some scrapers (Fig. 4:6) and slivers (Fig. 4:7) in the material.

Only one chisel fragment has been found (Fig. 4:4). Originally the edge could have been about 5 cm. This find came from the mixed ploughed layer. From the same layer an elongated oval stone object with two hitting marks was extracted. It could have been used as weight.

Splinters of crystalline rock and one sliver were also found. Among these the fragments of Baltic red quartz-porphyry are the more interesting. The use of the latter was common in Saaremaa in the Stone Age.

Inventories were made at Kõpu in 1994, including the scanning of ancient shorelines between 25 and 30 m a.s.l. Seven new places were found within the distance of 1 km (Fig. 2). The cultural layer was hardly distinguishable — darker soil occurred only in the fireplaces and finds were from a slightly cindery soil. 1.5 x 2.0 m trial pits were excavated at point VIII (Fig. 2). This site contains a lot of quartz fragments and objects, flint and polishstone fragments. At site IV (Fig. 2) the cultural layer is situated beneath a dune and, after the removal of the sand, one fireplace with stones covering 1.5 x 2.0 m was found. No ceramics were found in these sites. We can only assume that points IV and VIII, which are situated at 28–30 m a.s.l., could be derived from the pre-ceramics period.

Often the archaeological finds do not allow an exact determination of the age of a site. According to the Estonian division of prehistoric periods, in which the Neolithic starts with the use of pottery (Jaanits et al. 1982), the absence of ceramics above a height of 27 m at Kõpu (Kõpu IV and VIII) suggests that these places were used in the Late Mesolithic. Alternatively, the absence of ceramics may be explained by the fact that people did not take many vessels with them to a site which they used only seasonally. They returned to their base camp with pots full of oil and no pieces of ceramic were left behind on the island. More exact determinations can only be obtained by using a combination of different dating methods. For example, ceramic finds coupled with radiocarbon dates which indicate the Neolithic, or an absence of ceramics, but older ¹⁴C ages which indicate the Mesolithic and so on.

Some new radiocarbon datings were made on charcoal from Kõpu site I in 1994. The results are shown in Table I. On the basis of these we can conclude that the Kõpu I site represents the Early Neolithic Narva culture.

All soil excavated from Kõpu site I was sieved with 1 and 2 mm hand-sieves. Altogether 3618 bone fragments were analysed or counted. Macromammal bone fragments smaller than c. 0.5 cm² are not included here. About 24 % of the bones were burnt. Of the total material there were only 549 fragments which could be successfully identified to species or as seal bone.

The results of the bone analyses show that the greater part of the animal remains come from seals, and that only the ringed seal (Pusa hispida) and the grey seal (Halichoerus grypus) were hunted (Table II). The former is represented by 54 fragments from a minimum of 6 individuals and the latter by 45 fragments from 4 individuals. Bad preservation conditions in the sandy and stony soil prevented the identification of a large number of seal bones (433).

Large numbers of seal bones are typical of Neolithic coastal sites around the Baltic Sea (Forstén and Alhonen, 1975; Ericson, 1989; Lepiksaar, 1986). Four species of seal have been found from the coastal area of Estonia in different prehistoric periods. These are the grey seal, the ringed seal, the harbour seal and the harp seal (Lepiksaar, 1940; Tsalkin, 1952; Paaver, 1965; L. Lõugas, 1992, 1993, 1994). The latter species was more common at the end of the Neolithic (Subboreal climatic period) and probably entered the Baltic seasonally during its southward migration in autumn (Lepiksaar, 1986; Lõugas, in press). The absence of harp seal remains in the material of the Kõpu I site (also the Kõnnu site on the island of Saaremaa) is not a surprise, because the oldest finds of this species in the Baltic, from the island of Gotland, Sweden, are dated by radiocarbon method to 5245±60 BP and 5020±60 BP (Lindqvist and Possnert, in press) and/or the hunting season and technique for the harp seal differed from that of the ringed seal and grey seal.

The hedgehog (Erinaceus europaeus) is a very interestig find, because this species cannot populate isolated islands by itself. The hedgehog must have carried a magic meaning for prehistoric people. These 4 mandible fragments (Table II), found from a fireplace at the site, could have been brought to the island with the skin or as part of a complete skull. The site seems to have been used only during the seal hunting season, in early spring, when the hedgehog is in hibernation. It is, therefore, doubtful that a living animal had been brought to the site.

Bird bones were very badly preserved and in the form of small fragments. The location of the ancient Kõpu Island was very favourable for birds of passage as a resting place during their south-north migrations. This island, with a lake (later a bog) in its centre (Fig. 1), offered good conditions, especially for water birds. Probably a lot of ducks and gulls nested on the island and hunters were able to use their eggs for food in the spring. The remains of eider (Somateria mollissima), ducks (Clangula hyemalis and/or Bucephala clangula), cormorant (Phalacrocorax carbo) and red-breasted merganser (Mergus serrator) provide evidence of water bird hunting. One phalanx of the white-tailed eagle (Haliaëtus albicilla) has been found, but this is not sufficient to prove the hunting of this species on the island because the leg of the bird could be used in some ritual ceremony.

Even though all the excavated soil was sieved, very few fish species were represented in the bone material: only pike (Esox lucius), cod (Gadus morhua) and turbot (Scophthalmus maximus). The finds of cod and turbot indicate the existence of Atlantic forms in Estonian waters already at that time. The small amount of fish remains could be the result of bad preservation conditions or could indicate the absence of fishing among the prehistoric settlers of Kõpu. The main reason for coming to the island was most likely seal hunting. It is also possible that the few fragments of fish bone came from the entrails of seals.

There is some evidence that the Kõpu I site (probably all the sites I–VIII) was used only at a certain season of the year — in early spring. Firstly, this time is best for hunting the grey and ringed seal. One subfossil femur of the ringed seal was the same size as the femur of a recent individual weighing about 10 kg. This specimen could be only a few days, at maximum a week, old and so must have been hunted at the end of March or beginning of April. Secondly, the possibilty of using the site throughout the year is quite doubtful, because the island was only about 5 km² in size, 80 km from the mainland and 40 km from Saaremaa, and did not offer any good food possibilities, except for fish and seal, which are usually seasonal food. The hazelnut shells and some bigger tubular bone fragments (elk and/or wild boar ?), which were recovered from the Kõpu I site, seem to have been brought to the island by people. It is possible that the hazelnuts are local, but the distribution of big terrestrial mammals to such a small, isolated island, where the relevant ecological niche is limited, is almost impossible.

One seasonal dating method is based on fish vertebrae. The annual rings allow a determination of the approximate season in which the fish died (Casteel, 1976). The annuli on the vertebral centrum of pike and turbot (both were 3 years old) from Kõpu I indicated that the fish had been caught in March or April.

The study of the Stone Age habitation of the Kõpu Peninsula is in its initial stages and so these conclusions are only preliminary. It is evident that the southernmost coastal part of the peninsula was used for quite a long time, from the Late Mesolithic to the Early Neolithic. A thin cultural layer, the monotonous nature of the find material, the scarcity of hewing equipment, an absence of middens and a lot of seal remains indicates the seasonal use of the site by seal hunters. Mesolithic and Early Neolithic finds are quite similar, both with respect to the type of material and the objects. Possibly, people came to the island from a certain region to hunt seals, and successive generations have returned to the same place for thousands of years to hunt seals in the main season.

The southernmost part of the ancient Kõpu Island was a strategically favourable place for seal hunters. A gently sloping coast offered better resting and also breeding conditions for seals in winters of pure ice formation (typical of the Atlantic period) than the north coast of the island. At the time of existence of the Kõpu I site sea level was approximately at a height of 20–22 m above the present sea level (Fig. 2 and 3). The hunters chose their stopping place on the higher (25–27 m a.s.l.) dry beach ridge.

The ceramics from Kõpu I help us to explain the cultural origin of the prehistoric settlers. In general lines the fragments of pottery belong to the same group as the Narva Type ceramics. More similarities are noticed with Kõnnu ceramics from Saaremaa. Probably the sites at Kõnnu and Kõpu represent some kind of local phenomenon of the Narva Culture. The seal hunters who stopped on the Kõpu Peninsula may have come from Saaremaa or from the West Estonian mainland, but we do not know yet of Early Neolithic sites from the latter region.

We would like to thank Professor Urve Miller of the Department of Quaternary Research, Stockholm University, for her kind support and help in interdisciplinary research involving archaeology and the natural sciences. We also thank Dr Tanel Moora, Institute of History, Estonian Academy of Sciences, for valuable discussion and help with the field work, Dr Vello Lõugas (same institution) for discussion, Jana Ratas, Art University, Tallinn, for drawing the figures, Dr Elvi Tavast, Institute of Geology, Estonian Academy of Sciences, for analysing the malacofauna, Dr Shiela Hicks, Oulu University, for linguistic revision, Dr. Christian Lindqvist, Stockholm University, for participation in the excavations and discussions, and all students of Tartu University who took part in the archaeological excavations in Kõpu in 1994.

During this investigation, all of us were researchers on a grant (No. 1022) provided by the Estonian Scientific Foundation. The Institute of History, Tallinn, partially supported these excavations in the summer of 1994 and during later studies. Lembi Lõugas also thanks the Nordic Council of Ministers for financial help during her studies in Sweden and Dr Leif Jonsson, Gothenburg, for help with the bird bone determinations.

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