Pearl Fishing in Sweden: From the Middle Ages to the 20th Century

This is an English version of my post Pärlfiske i Sverige -- från medeltiden till nutiden. Please regard this as a first translation, most likely in need of revisions.

I will write more articles in the future, both translating writings from Manekis Pärlblogg and doing new texts especially for this blog. If you have any suggestions for themes, please don't hesitate to ask.

~*~

Sweden isn't especially well-known as a producer of freshwater pearls, but the fact is that pearl fishing has occured in different parts of the country during centuries. It didn't cease until the freshwater pearl mussel became protected by law in the 1990's due to a rapid decrease in population.

(The pearls in the photo above are not Swedish, they are -- as most freshwater pearls today -- cultured Chinese.)


The freshwater pearl mussel
The highly coveted pearls are formed in the freshwater pearl mussel (Margaritfera margaritifera). The scientific name, margaritifera, means pearl bearer. This mussel live across the Northern hemisphere, mainly in temperate zones, but has its main distribution in Northern Europe. Here it lived fully or partially hidden i sand, stone or gravel bottoms of unpolluted, clear and streaming waters. It is today an endangered species and larger colonies can only be found in Canada, North-western Russia and Eastern Scandinavia. In Sweden, the most famous habitat is Pärlälven (Silbbaädno) in Jokkmokk municipality in the North. Pärlälven literally means the pearl river.

The species as existed for 80 million years on Earth, but it has dramatically declined the last 100 years, partially due to overfishing in the hunt for the valuable pearls. In Sweden, it has disappeared from every third known habitat. In the agricultural areas of Southern and Mid Sweden it has more or less totally disappeared.

The mussel is one of the most persistent molluscs and it can live for over a century -- the oldest found mussel became 256 years, which could be read from the "annual rings" of the shell. How old a mussel can get depends on the environment of the habitat: natural changes in the waters mean that mussels get older in the North than in the South. Pearls only form in mussels older than 20 years. Growing a pea size pearls takes another 12-20 years.

Pearls are formed when a foreign particle, e.g. a parasite, enter the mussel while it inhales water for breathing and filtering out organic particles for nutrition. If the particle can't exit the mussel again, the mollusc protects itself by covering the irritant with layers upon layers of nacre from the mantle, a soft tissue on the inside of the shell. Nace mostly consist of crystalline calcium carbonate and an organic horn-like compound. Nacre is also known as mother-of-pearl (in Swedish pärlemor, meaning exactly the same) because of this.

It is not common for mussels to grow pearls, which makes non-cultured pearls very rare, no matter the size of the mussel or oyster population. About one in 50 mussels contains pearls (usually 1-3 in each), but only about one in every 2 000 or 3 000 contains aesthetically pleasing pearls that can be used in jewellery. Due to the long time it takes to grow a pearl, large specimens are uncommon. The largest pearl ever encountered was close to 13 mm i diametre. The shape can vary greatly while the colour is usually blueish white, but it can also have tones of pink or baby blue.

Illustration from Alfred Edmund Brehm's Tierlieben (1864-9).

The history of pearl fishing in Sweden
Already during the Middle Ages, pearls were sought after in Scandinavia. In those days Swedish pearls came from Finland, which was for centuries a part of the Swedish kingdom. It was said that Karelian peddlers fished for pearls while travelling across Österbotten. There was a lack of domestic pearl fishing so most of the demand for pearls by the court, rich magnates and the church was satisfied by imports.

But there was an interest in avoiding this import. Gustav Vasa, (Gustav I, king of Sweden 1523-1560), issued a passport and letters of recommendation for a russian citizen, Demanth Riiss, who was in Stockholm at the time. He was ordered to return to his homeland and there obtain pearl fishers with diving experience. The fishing was also stimulated by offering privileges for citizens (burghers), allowing them to trade with pearls in several Swedish and Finnish towns. In 1544, Vasa called for the bailiff (fogde, vogt) of the provinces of Ångemanland and Medelpad to buy all pearls that was found. Simon Andersson Skrivare was sent out to investigate which Northern rivers might contain pearls and to purchase the pearls on the behalf of the king. The local pearl fishers were banned from selling their catch to anyone but the royal envoy, according to the orders the bailiffs received from the king.

The interest in pearl fishing took off in the early 17th century, perhaps stimulated by a 1643 book, depicting what richness the mussels in the country could pose. The Crown began to employ "pearl and gemstone fishers" of its own and later, in 1691, the pearl fishing became a royal privilege. In Stockholm a senior inspector of pearl fishing, överpärlfiskeinspektör, was installed and there were also several local officials stationed to keep control.

The province of Västerbotten (today's Norrbottens and Västerbottens län) was absolutely dominant and in the end of the 1690's purchases from any other places in principle ceased. The fishing was as most intense during a few years in the end of the decade in Lule lappmark, were it probably came to play an important role in the Swedish colonization of Norrland, the Northern parts of Sweden. The Saami did not fish for pearls in the same degree as the settlers did.

But the fishing wasn't always very fortunate. The last years before it ceased to be a royal privilege in 1723, the pearl fishing had ended in almost the whole country, with the exception of Northern Norrland. There it would continue a few years into the Age of Liberty (1718-1772). It was only during a few initial years that the Crown had made a slight profit. The remaining time was directly unprofitable. In addition, the pressure on the mussel populations depleted them in several ares. In the early 18th century, it was reported to be the case in the Northern coastal areas. Further from the more densely populated coasts, the fishing continued during the 1720's and in 1731 the pearls once again became a royal privilege. In 1734, Karax -- an area including the afore mentioned Pärlälven, was considered to still be of a certain interest for pearl fishing.

When Carl von Linné (Linnaeus) visited the area in 1723, a decade before, he noted that the populations of freshwater pearl mussels were almost depleted by the fishing. He was told that a man could open up to 1 000 mussels to find one pearl. All this made him start experimenting with pearl farming in the Fyrisån river in Uppsala where he worked at the university. He was inspired by the pearl farms known to exist in China. The method he developed consisted of drilling a hole in the shell of the mollusc and, using a silver wire, insert a fragment of limestone to stimulate pearl growth. The experiments can be seen as part of the trends of the time, when many efforts were made to try and produce luxury goods within the country, which otherwise could only come from dependence on imports or having a large empire. Others tried, in vain, to grow saffron in Norrland, attract Russian sable by planting trees, or grown mulberry bushes for silk productions. More successful examples included cultivation of tobacco, medicinal herbs and potatoes. Linné received a reward from the government for his attempts in pearl fishing and his idea was sold on to others, but it never came to any form of practical use.

The period 1691-1723, organized pearl fishing seems to have led to a rapid and very serious depletion, and again in the 1770's the Crown gave up its monopoly on the fishing due to non-viability. But there is an indication from the 1860's, showing that the state of the mussel populations in Pärlälven was much better at that time. The then crown prince Karl could at that time buy pearls from two deep dishes, which he had made into a full set of jewelry (including tiara) for his crown princess. During the 19th and 20th century, the fishing was conducted privately and in some places it could still be a profitable business.


Pearl fishing in the 20th century
During the last century, pearl fishing was conducted in several rivers all over Sweden. But extensive fishing is mainly attested from Pärlälven and Råneåälven (Lappland), Västerdalälven (Dalarna), the waters in Jämtland, Svartån (Östergötland), Emån (Småland) and Lagan (Halland). In other words, river in both Northern and Southern Sweden. From Lagan's lower reaces, it is told, that pearls for close to 30 000 SEK was found during the summer of 1911. Close to the river lived crafter Paulus Cederholm, who made jewelry and trinkets from the mother-of-pearl discarded by the pearl fishers.

In Älvsborgs län, the pearls were an ancillary to the salmon fishing and agriculture. Fishing pearls was especially suitable as a mean of additional income as it could easily be combined with the work on a small-scale farm. When log-floating and mowing required much time and labour, the water levels were too high for gathering pearls, but at the same time of the year when the most intense work on the farm was over, the water levels receded to appropriate depths. The fishing could sometimes make a significant contribution to the family's economy, together with the agriculture, log-floating, fishing and forestry. Especially as the prices of pearls were high at the time. In the 1950's, a pearl fetched 100 SEK per millimetre in diametre in Northern Sweden. That could mean a couple of thousands during a summer, a pearl fisher told, even it it also could mean weeks and months of work just to find one prima pearl. A rich farmer family was considered to have gained its wealth through pearl fishing in Emån river. The most famous pearl fisher, Oskar Skoglund from Eksjö, found about 150 pearls during 44 years of searching, resulting in an additional income of 7-8 000 SEK.

At various scales, the pearl fishing exsisted well into the second half of the 20th century, eventhough for example the Pärlälven was protected by law in 1914. It wasn't until the freshwater pearl mussel was protected throughout Norrbottens län that the fishing actually ceased there. In Lagan, professional pearl fishing carried on in the 1930's. In 1994, the mussel was protected nationally and pearl fishing hence became illegal.


How pearl were fished
As you see, I keep referring to the act of harvesting pearls as pearl fishing, while most people have only heard of pearl diving. The common practise in Sweden was not to dive for pearls, but rather use special tongs to pull the mussels from the bottom of the rivers.

In order to fish pearls, the fisher would wade into the water -- a common method, especially in smaller streams -- or sit in a boat. Regardless which method he used, he needed two tools: pärltång (pearl tongs) and pärltub (pearl tube). Sometimes he also had a bag to collect the mussels in. The "tube" was kind of a homemade "underwater looking-glass", that could also serve as a basket to collect the mussels in. The tongs were used to pick up mussels -- as you can see in this authentic footage -- and they were usually forged by either the pearl fisher himself or by a blacksmith. The iron tongs were equipped with long wooden handles that could be extended to up to seven metres depending on the depth of the waters. Some tongs instead had a shaft and spring that was controlled by a rope.

The origin of the pearl tongs was a clamp, used since medieval times. The clamp ws made from wood or bamboo and had a forked end, which was pressed over the mussel. At low tide, mussels could also be collected by hand or by sticking a pointed stick into the opening of the mussel, making it close the shell and thus remain clamped on the stick while it was pulled from the water.

Residents by the rivers had the advantage of using boats for fishing, which meant they could reach depths were no one else had already been searching by wading. Around Pärlälven special pärlekor (pearl rowing boats) were built. They differed from other boats by having straight end in both stern and bow. The pearl tube was fastened to the bow, using a bolt so it could swivel. Usually there was two men in the boat: one man to pull out the mussels using the tongs and one man operated the boat using a pole. It is said that boys could be made to jump from the boat with a stone in the arms to pick mussels from the bottom of the river, like Asian pearl divers. In Jämtland they also used pärlhåvar (pearl nets), that were dragged by boats like bottom trawls, to gather the mussels.

At this time, some organized expeditions to Lappland and Norrbotten with divers and equipment. The divers could reach greater depths, but they were not more effective than pearl fishers using traditional methods in the end.

Pearl fishing continued also during the winter. Either a hole was cut into the ice so tongs and tubes could be inserted or men would wade into the open wells, forming in the rapids where the ice would not freeze -- places impossible to reach during summer.

When the mussels had been gathered together on the beach, the pearl fishers would sit down and open all mussels using blunt knives. A blunt edge was used so the knife would harm any pearl that might be inside. Some fishers used mussel shells instead of knives. After the mussel had been inspected, it was thrown back into the water. Opening a mussel like this kills it as the muscule is cut off. Milder methods using special pliers that didn't kill the mussel so it could be re-introduced to the waters exsisted, but they were rarely used. The practise of killing mussels when opening them was an effective way of depleting the populations.

There are many different claims as to how many mussels a fisher would pick in a day: so say 100 while others say 20 000. It could take a couple of thousand opened mussels just to find one pearls -- and it was even more rare to find large specimens. The fishers had tricks to recognize pearl-bearing mussels, called pärltecken (pearl signs). It could be damages or deformations on the mussel shell, rugged surfaces, a stripe along the shell etc. However, it is questionable how useful these signs were.

Photo by Joel Berglund (via Wikimedia Commons), used in

accordance to Creative Commons Attribution-ShareAlike 3.o.

Protection and environment
Already Linné, while travelling through Dalarna, was worried about the freshwater pearl mussel becoming extinct through the extensive fishing. In the 20th century new threats appeared, besides the overfishing. The mussel need clean and unpolluted waters and at that time, a dirty industry began to have adverse effect on nature, as did agriculture and forestry. Water pollution, the cleansing of river bottoms for log-floating, water regulations (dams), acidification, and eutrophication has made it hard for the mussel to survive. Since the fishing was banned in 1994, forestry, acidification, and eutrophication are considered the main threats to the Swedish trout, which plays an important part in the mussel reproduction. Forestry contributes to an increase of particles in the water -- leading to sludge clogging river bottoms that choke young mussels -- through drainage, cultivation and driving in or close to the waters. The trout is also threatened by the sludge and acidification as well as beening injured by the cleansings for log-floating, thus being an indirect threat to the mussels' survival.

Today the mussel is protected by law throughout the EU and in Sweden it is classified as vulnerable. Actions are being taken to prevent the extinction of the species. Pärlälven is today, at least partially, a part of a Natura2000 area called Pärlälvens fjällurskog. The purpose of this nature preserve is to preserve the character of the landscape and let the ecosystem evolve in a natural way. The river is also popular with anglers.

~*~

Sources:
Awebro, Kenneth & Thomas Öberg: Pärlproducent och miljöarkiv. In Pettersson et al (eds.): Människan och naturen. Etnobiologi i Sverige 1. Wahlström & Widstrand.
Folklivsarkivet, Lunds universitet: Pärlfiske
Landell, Nils-Erik (2001): Sveriges välstånd om det vill. In Pettersson et al (eds.): Människan och naturen. Etnobiologi i Sverige 1. Wahlström & Widstrand.
Länsstyrelsen i Norrbottens län: Välkommen till Pärlälven!
Sveriges Radio: SR Minnen -- Pärlfiske. Om pärlfiske i Jämtland. From August 27, 1940.
Wikipedia: Flodpärlmussla [Freshwater pearl mussel]
Wikipedia: Pärla [Pearl]