Crayfish Gastroliths

It’s the time of the year when it used to become legal to catch and sell Swedish crayfish, and so the grocery stores sell Turkish and Chinese crayfish for a few weeks. The traditional way to eat them is to boil them with dill, salt and a little sugar, and serve them with toast, strong cheese, beer and akvavit. I don’t drink but I love shellfish, so crayfish time is always a treat for me. My wife, being refreshingly unorthodox about traditional Swedish customs, and indeed about all traditional customs thanks to a Maoist childhood, served crayfish with smoked shrimp, aïoli and boiled potatoes last night.

There’s a fun detail about these animals: sometimes you find a pair of little white buttons in their heads. These are known as kräftstenar in Swedish, “crayfish stones”, and gastroliths in English. (The same word is also used for actual stones eaten by crocodiles, birds and other dinosaurs to help digest their food.) As Andrew Hosie of the Western Australian Museum explains:

… crayfish gastroliths … represent a remarkable physiological process to conserve calcium.

Much like people require calcium for strong and healthy bones, so too does a freshwater crayfish to maintain its armour. … As crayfish (indeed all crustaceans) grow bigger, they must periodically shed the exoskeleton and form a new one. To start a new exoskeleton from scratch would require large amounts of new calcium.

The hormones that drive moulting (referred to as ecdysis) trigger calcium carbonate to be removed from the exoskeleton and starts forming a pair of these gastroliths in the stomach. After the crayfish has moulted, the gastroliths are reabsorbed and used in the strengthening of the new exoskeleton. Only freshwater crustaceans form gastroliths because unlike seawater, freshwater has very little dissolved calcium salts, so in an effort to retain calcium, crayfish form these little gastroliths, or even eat the old exoskeleton.

Check out the strange story of what my friend Eddie unexpectedly caught in his crayfish trap.

Friday Mushrooms

zvampHas it really been almost four years since I blogged about mushrooms? This afternoon me and my wife repeated our September 8, 2010 expedition to the hills between Lakes Lundsjön and Trehörningen and picked almost a kilo of mushrooms in a bit more than an hour. We got:

  • King bolete, Stensopp/Karl Johan, Boletus edulis

  • Bay bolete, Brunsopp, Boletus badius
  • Orange birch bolete, Tegelsopp, Leccinum versepelle
  • Birch bolete, Björksopp, Leccinum scabrum
  • Entire russula, Mandelkremla, Russula integra
  • Two kinds of red or brown brittlegill, mild-tasting and thus non-poisonous. Scandyland has more than 130 species of brittlegill, none are deadly and luckily there’s a simple taste test for which ones are good to eat.

Another sensational "human face" naturalistic, anthropomorphic clay figurine from Jokiniemi!!!


The extensive media coverage of the Science Center  Heureka dig in Jokiniemi 2014 has brought to light  a sensational find made by an amateur geologist (with a great eye for archaeological artefacts) in Jokiniemi some 10+ years ago.

The newly reported and amazingly detailed figurine is very realistic and shows tattoos and/or face paintings very similar to those of the figurine found during the Heureka excavation in 1990. On this new figurine the tattoos below the eye sockets seem to be "net" shaped.

Picture by kind courtesy of Mr. Harri Römpötti/ edit Jan Fast

Below is another  of this figurine taken around the time the find surfaced. Some of the features have been enhanced in red. It´s been kept safe and in good hands since then by the finder. I expect to be able to meet the figurine "in person" some day very soon.

Picture by courtesy of Mr. Harri Römpötti/edit Jan Fast

Personally I take no credit whatsoever for this sensational find but would  instead like to take the opportunity to congratulate the anonymous finder on this amazing find! This is truly a happy day for responsible amateur archaeology in Finland and for archaeology in the Baltic Sea region and  beyond :)

Första veckan i Hossmo!

Denna vecka inleddes den arkeologiska undersökningen i Hossmo, på den plats där vi tidigare konstaterat spår av en forntida väg tillsammans med spridda lämningar av lite finare sort från den yngre delen av järnåldern, omkring 500-1000 e.Kr. Utgrävningen är en del av undersökningarna inför den nya E22 förbifart Rinkabyholm söder om Kalmar. Förutom i Hossmo gräver vi även i Skyttlahagen, där vi började redan förra veckan.   Förväntningarna inför undersökningen i Hossmo har varit lite blandade; vi har hela tiden vetat att vi är något mycket intressant på spåren, samtidigt verkade det utifrån förundersökningarna som att vi inom undersökningsområdet inte kommer att kunna fånga upp särskilt mycket utan nog mest befinner oss utanför händelsernas centrum. Utöver den forntida vägen hade vi hittat rester av en ugn och en del spridda lämningar i form av eldstäder och stolphål,


For the last couple of months I have been engaged in research concerning the history of two river systems in Sweden: Göta Älv and Ätran. I have tried to explore questions of river/human interaction and several interesting themes have emerged. In my research I have focused on six case studies, and this blog post concerns one of them: Åkerström.

 A map of Göta Älv with some important places marked.

For anyone interested in the history of Göta Älv – the largest river in Sweden which enters the ocean at the area surrounding Gothenburg – Åkerström is a place of significance for several reasons. The river has been used for transport for many centuries and Åkerström is intimately tied to the transport economy of Göta Älv on many levels. Furthermore, the Göta Älv valley has long been plagued by natural disasters which historical effects can be clearly seen in this area. The river should not be seen as something passive in this region, as its nature and effect upon the surrounding landscape clearly has affected the human society of the area.

  The pre-medieval history of Åkerström remains largely unknown and unexplored. The only nearby remains of Iron Age activity is an ancient hill fort on a mountain overlooking the river channel just to the northwest of the 17th century farm Slätthult. Almost no burial features can be found here, apart from a few stone settings and stone circles to the north of Åkerström. Thus it seems like the local area was pretty much uninhabited during the Iron Age.
   During the Middle Ages, the main area of settlement lay to the north of Åkerström, between present day Trollhättan and Vänersborg. This area was highly suitable for farming with soils consisting mainly of clay and silt. The vicinity to Vänern and the extensive forests surrounding this settlement area also provided the foundation for a diverse amount of secondary resource production. Cattle farming was the most important agrarian resource of this area and cattle – along with its byproducts – was highly valuable trade goods.
   It is difficult to say with any certainty to what extent this region of Göta Älv was used for transport during the medieval period. Considering the picture that emerges during later centuries it is highly likely that the whole river has been used at least sporadically for transportation during the Middle Ages. However, the falls at Lilla Edet and Trollhättan were difficult obstacles for upstream transportation, and it is perhaps more likely that Göta Älv was used for downstream transports during this period – such as timber rafting. The difficulties of these water falls are well emphasised the later development, where a road called “Edsvägen” connected the river north of Trollhättan to Åkerström. Goods where traditionally unloaded at Trollhättan and transported by land to Åkerström. From Åkerström the goods could be shipped to Lilla Edet where it had to be transshipped again – at least before the middle of the 17th century when a river lock was constructed there by King Karl the IX of Sweden. 

A georeferenced and digitised version of the 17th century map of Åkerström on top of a modern orthophoto. The original map can be seen here: Map of Åkerström (National Archives)

   Åkerström should therefore be seen as a rather liminal area up till at least the 16th century, when it first appears in the written records. When we take a look at a map of the area from 1653, the location is obviously entangled in the river economy of Göta Älv. The map mainly surveys the farms of Slätthult and Stubbered, but also shows the location of Åkerström – where some “iron huts” where located – as well as the border stream between Denmark and Sweden. In 1648 a landslide occurred in this area, which had disastrous effects on the settlements downstream. Several ships and houses were destroyed, and the earth masses blocked the entire river valley. When the water eventually broke through the dam of soil a huge “tidal wave” swept down the valley, causing severe additional damages. The location of this landslide (called “Stora Jordafallet”) is also marked on the map.

   The farms of Slätthult and Stubbered were by no means disentangled from Göta Älv, and had access to fishing waters in the river. In addition, Slätthult made “good revenues” from barges going down Göta Älv towards Gothenburg. We can only guess at the nature of these barges, but the farm obviously produced timber which would have been easily transported down the river. Timber rafting on Göta Älv was common during the 17thcentury, but most timber came from more distant places, such as Värmland and Dalsland. Here is then an example of a local entrepreneur who was engaged in the larger economic structures of Early Modern Sweden, and who used them for his/her own gains. We cannot know the historical depth of this phenomenon. According to some authors, timber rafting occurred on Göta Älv already during the Middle Ages. Even though this is indeed possible, scarce evidence exists.

   Perhaps even more interesting are the two abandoned sawmills which lay on the lands of Slätthult. It is highly likely that the timber industry of the area suffered from the landslide in 1648, which would explain the abandoned saw mills. No real trace of these sawmills can be seen today, as they seem buried beneath large amounts of rocks which have fallen from the slopes to the south-east. 

   That was a short account of the area of Åkerström during the Early Modern period. The place is highly interesting, and an investigation like this raises additional questions:

·         The water falls at Trollhättan were used for milling during the 15th century, which indicates that the vicinity was settled. Is it possible that the trading station of Åkerström was active already during the Middle Ages?

·         Was local private engagement in long-distance trade something common during the Early Modern period?

·         Was the area surrounding Åkerström politically important in some way due to its economic function?

·         If so, where are the physical traces of this importance located?

Husbyborgs historia och förhistoria

Just nu undersöker vi boplatslämningar från förhistorisk tid vid Husbyborg i Uppsala. Området ligger på västra sidan om Fyrisån, uppströms från centrum och idag blandas här jordbruksmarker och industri- och kontorslokaler. I höstas utredde Ulf Celin, Ann Lindkvist och Olle Heimer ute ett större område med anledning av att industriområdet behöver expandera. Uppe invid ett impediment hittades härdar, gropar och stolphål inom en yta som kunde begränsas ganska väl – tyvärr beroende på att nutida bebyggelsen förstört delar av den ursprungliga boplatsen.

Häradskarta från 1859-63, med det ursprungliga utredningsområdet i rött. Boplatslämningarna kom i NÖ delen, intill det impediment som kan ses på den gamla kartan. Gränserna mellan ägorna går tillbaka till storskiftet 1767. (Karta: Ann Lindkvist, från SAU Rapport 2013:20, fig 3).

Det äldsta skriftliga belägget för Husby-namnet är från 1345 då platsen benämns Husabyulleråker (SAU Rapport 2013:20, s 10). Förmodligen har det redan då ett par hundra år på nacken, för de flesta husabyar verkar bildas under 1000-1100-talet. För Uppsala-arkeologer är namnet Husbyborg framförallt förknippat med det hus som rymde de omfattande samlingarna från arkeologiska forskningsgrävningar utförda av institutionen. Inte bara från Sverige utan även Egypten, Cypern, Grekland och Turkiet. Numera ligger ansvaret för samlingarna på universitetsmuseet Gustavianum och de har precis flyttats till nya och mer ändamålsenliga lokaler i närheten av campus. En flytt som för övrigt Ulf Celin var inblandad i mot slutet som projektledare, så han har verkligen hunnit bli bekant med platsen.

Ulf Celin och Kerstin Westrin schaktar fram spåren av järnåldersbebyggelsen vid Husbyborg. Foto: Niklas Stenbäck

Boplatslämningarna som Helena Hulth, Ulf Celin och Kerstin Westrin är ute och undersöker 2014 är dock äldre än det medeltida platsnamnet, kanske mer samtida med efterleden ulleråker – ej att förväxlas med dagens Ulleråker i södra Uppsala (läs mer om den mystiske Ull i SAU Rapport 2013:5, s 9-11). De ligger framförallt samlade på de högre partierna och tunnas av ned i slänten. Tidigare undersökningar av Per Frölund i närheten gav lämningar från övergången äldre-yngre järnålder, dvs runt 200-600 e Kr (RAÄ rapport ATA dnr 6781/93). Det verkar passa ganska bra med utseendet på de anläggningar som framkommer meddelar Helena, kanske med mer övervikt på yngre järnålder. Men det kommer vi inte veta ordentligt förrän resultaten från kol14-dateringarna blir klara.

Det kommer fler inlägg om Husbyborg framöver under rapportarbetet.

Arkeologi inför Ullevileden

I förra veckan påbörjade vi en arkeologisk slutundersökning inför byggnationen av en ny ringled, Ullevileden, i Linköping. Undersökningen berör två boplatser: RAÄ 342 vid fd Aspegården och RAÄ 503 vid Åby Västergård.

Vi har startat med boplatsen vid Aspegården, i närheten av varuhuset ÖoB. Den drygt 2600 m2 stora ytan är nu framschaktad med hjälp av grävmaskin och vi har hittat ca 150 boplatslämningar i form av stolphål, gropar, härdar och kokgropar. Utöver det har vi även funnit resterna efter en förhistorisk väg. Bland stolphålen kan vi redan nu skönja ett hus men troligtvis finns det minst ett till. Dateringar från den föregående arkeologiska förundersökningen visar att de nu påträffade lämningarna troligtvis är anlagda någon gång vid århundradena runt Krist födelse, dvs äldre järnålder.

Just nu är vi i full färd med att undersöka alla anläggningar. Vi är tacksamma för att den stekheta sommarvärmen är över. Dock får vi dagligen besök av en sällan skådad mängd nyfikna getingar…

Den första september rullar vi vidare och börjar med undersökningen vid Åby Västergård.   

Återkommer snart med vidare resultat!

Fredrik Samuelsson

Fältprojekt Västra Vång 2014 avslutat

Grävplatsen i Vång 2014 fotograferad mot NNO.

Årets grävning i Vång har genomförts planenligt under den gångna sommaren. Inte minst har detta kunnat ske genom ett ivrigt deltagande av frivilliga arkeologer i alla åldrar. Även publikt har säsongen varit lyckad, med ett ständigt flöde av intresserade besökare. Samtidigt har Vångutställningen inne i Karlskrona lockat, och många har tagit chansen att bese både den och den pågående grävningen. I skrivande stund avslutas dokumentationen, grävplatsen städas och schakten läggs snart igen. Sammanlagt handgrävdes mer än 200 kvadratmeter för hand i åkermarken, vilket är den största sammanhängande yta som undersökts i Vång sedan 2005. Vi kan konstatera att resultaten utgör ett viktigt komplement till den tidigare kunskapen om den förhistoriska boplatsen.

Grävning av 1-metersrutor samt arbete vid såll och hackbord.

Förutom förväntade anläggningsspår påträffades ställvis kulturlager, vilka inte påverkats av plogen. Fyndmaterialet domineras kraftigt av keramik, men schaktet präglas i övrigt av omfattande belägg för främst textil- och metallhantverk. Tidsmässigt verkar årets lämningsspår preliminärt kunna placeras inom intervallet folkvandringstid – vikingatid. Den som är mer intresserad av årets resultat, och vill se ett urval av fynden, rekommenderas besöka Kulturcentrum i Ronneby på Arkeologidagen den 31 augusti. Då håller projektet öppet hus och svarar på frågor mellan kl. 11.00 och 15.00.

Väl mött!
Mikael Henriksson
Vång 2014 - fragment av folkvandringstida reliefspänne

Looking for co-operation in Lithuania and especially Latvia.

Especially on the subject of anthropomorphic clay figurines and contacts and  trade of amber in the neolithic in the Baltic Sea region. Please contact me asap at .

I´m planning a doctoral thesis on the subject of contacts via large dwelling sites in the typical and late comb ceramic periods in the Baltic Sea region. At the moment my main focus is on the comb ceramic finds from Gipka and Purciems regions in Latvia. All help is welcome!

Fredrik Bruno – back on Flickr Commons!

Kungsgatan street in Stockholm City, at the intersection with Sveavägen street. Photo: Fredrik Bruno, 1944.

Kungsgatan street in Stockholm City, Sweden. Photo: Fredrik Bruno, 1944.

Three years have passed since the Swedish National Heritage Board presented Fredrik Bruno and his 1940s colour photographs on Flickr Commons. Since the images have been largely appreciated, we thought it would be nice to renew the acquaintance and show some more of these photos from different towns around Sweden (and some from the countryside), taken with either Kodachrome or Agfacolor diapositive film. Being a professional town engineer, Fredrik Bruno obviously focused on urban motifs. A lot of the photos might even be from travels he made in his service.

When we first started the Fredrik Bruno collection on Flickr Commons in 2011, (read on our blog) we divided it in two albums, one with photos from Sweden, the other with photos from Norway. This time we will only upload photos from Sweden, because of a larger number to choose from.

Some of the photos we show have a link in the field of information to a recent photo in our photo database, showing exactly the same view, but in 2010-2011. These comparative photos were taken within a project at the Swedish National Heritage Board, with the purpose to illustrate changes in the urban environment over time.

It would be just great to see some of your own comparative photos posted in comments! Welcome to to enjoy the 1940s in colour, in our photostream on Flickr Commons or in the album “Fredrik Bruno – Sweden”.

View of Sundsvall town in Medelpad. Photo: Fredrik Bruno, 1944.

View of Sundsvall town in Medelpad, Sweden. Photo: Fredrik Bruno, 1944.