Fish Conservation in the Algarve in Roman Times

Peter Kingdon Booker


Ciclo de Conferências Sobre História do Algarve


Departamento de História, Arqueologia e Património da Universidade do Algarve


The second lecture in the series presented by lecturers of the University of the Algarve at Tavira Municipal Library Álvaro de Campos took place on the evening of Wednesday 17 December. João Pedro Bernardes, the university expert on Roman archaeology and history in the Iberian peninsula, spoke on “A Indústria Conserveira no Algarve Romano”.


The basis of the lecture was the industrial production of garum or fish paste in the Algarve. Conserving was done with either salt and vinegar, or fumado – tuna and pork were treated in the same way, and smoking was an especially Latin way of conserving fish. It is thought that there were differing qualities of garum, one more liquid, like a sauce and another more like a paste.


The Phoenicians were the first to sail round the Mediterranean, and they were the first to make the conservation of fish an industry. Their processing tanks were located around Cadiz and in point of fact, conserving tanks have been found around the Sado estuary, along the Algarve coast, along the (now Spanish) Atlantic coast of Baetica, down the Atlantic coast of Morocco, and inside the Pillars of Hercules in the Mediterranean along the coast of North Africa and on the coast of what is now Southern Andalusia. In the ruins of Pompeii which was buried in volcanic ash in 79 AD some amphorae have been found marked with writing that shows that Clarus of Ossonoba´s product was loaded in Cadiz from the warehouse of M Valerius Abinnericus. We deduce from this find that Cadiz was used by the Romans as a major exporting centre for the processed product, and that it was collected there in order to make up shipments to parts of the Roman Empire. It may be that Cadiz had the same function under the Phoenicians. We deduce that this industry was developed during the Phoenician period and continued through the whole of the time of the Roman Empire, until some time around the fifth century.


Salting or conservation tanks have been found in the Algarve in at least 29 locations from Beliche in the west to Cacela in the east. We deduce nowadays that so many tanks cannot have been used solely for domestic or local consumption, and that the product must have been destined for export. Twenty years ago it was thought that the production of garum was only for home consumption.


After about 170 AD the Iberian peninsula suffered from invasions by the Mauri from North Africa and although there is evidence of continuing trade, Cadiz and its environment never regained its former prominence. The conserving industry carried on however and the tanks particularly in the western Algarve were as numerous as ever, and were probably controlled from a centre in Ossonoba.


The profusion of mosaics in the Algarve with fish motifs and marine backgrounds gives some indication of the importance of the industry in the region (there are good examples in Milreu, Portimão and Lagos). The fish which feature in these mosaics are sea bass, dories, groupers, squid and dolphin together with mussels and sea urchins. The major surviving mosaic work in Faro is that in the Archaeological Museum. The mosaic displays the head of the god Oceanus, and the marine iconography includes lobsters, crabs and dolphins in his hair. They were in the four corners of the image heads representing the four winds, and of these four two survive and are thought to represent Zephyrus and Boreas. This mosaic was donated by four prominent citizens of the town, whose names are shown in the mosaic and who are known to be from leading Algarvean families at that time. There are similarities with mosaics in North Africa in Libya, Morocco and Algeria, which in turn leads to the belief that the mosaic originated there, or at least the mosaicists were North African. The date of the mosaic is second or third century.


In antiquity, there was no reason to commemorate fish in this way. Persons of a high social caste would have wanted to commemorate important personages in the empire or provincial administration, and until late in antiquity the only sources of wealth which might have been symbolised in this manner and in a socially acceptable way were those originating in agriculture. It is conceivable that the owners of the fish mosaics were capitalising on a double motif - the fish as symbol of Christianity as well as the fish as pagan symbols of divine protection.


In Vilamoura there exist tanks for fish conserving as well as tanks for the production of ink or dye - tinta purpurea from the murex. This is the only such example known in Portugal. The precious violet liquid was bottled in small flasks known as anphoriscos, some examples of which have been recovered at this site.


The structures at Boca do Rio near Budens in the concelho of Vila do Bispo were investigated by the nineteenth century Algarvean archaeologist Estácio da Veiga who identified many cetárias; since his time many of the tanks have been lost to the sea. The relatively modern buildings on the site are those erected after the earthquake of 1755 for the Real Companhia das Pescas under the orders of the Marquês de Pombal, and they were built in the midst of the Roman remains.


It is a fact that many of these “sets” of cetárias were accompanied by bath buildings. In one case, an archaeologist from Northern Europe had posited that a hypocaust was used by the Romans for the evaporation of water in the preparation of salt; archaeologists from the Algarve dispute this deduction, since they know that in the Algarve salt production is reliant on solar power not artificial heat. Modern thinking is that the hypocausts were used for the acceleration of the fermentation of the garum with salt, herbs and vinegar as well as to warm up the water for bathing. Since there were so many different tanks and of differing sizes, it is possible that garum was made in differing qualities. In some of the tanks even now there have been recovered small particles of the original garum, and work is going forward to identify the species of fish in the tank from these remains.


At Martinhal near Sagres, as the sea erodes the cliffs, there is an area being exposed where ovens for the baking of pottery were located. Carbon 14 dating is being used to identify the last known date for the use of these ovens, and it appears that they were used in the 5th and 6th centuries. Work is being done to identify the cements used in the building of the cisterns, some of which were large, holding up to 103 000 litres of water. The water would have been used in the preparation of the clay for the making of the amphorae. Work is also being done to analyse the clays used in the area so that it will be possible to identify amphorae which originated in this area. There were of course other olarias in the Algarve, and we know of contemporary olarias (for example at Cacela and Manta Rota). At least one of these ovens would have been used for the production of building materials, tiling and rooftiles as well as for amphorae.


The lecturer was able on this occasion to offer to members of the audience copies of the recent publication “A Rota do Mosaico Romano O Sul da Hispania (Andaluzia e Algarve)” of which he was coordinating editor and which was first published in 2008.


Please note that it was announced at this lecture that the next in the series, “O Gótico em Santa Maria do Castelo”, will take place on Wednesday 21st January and not on 14thJanuary as previously advertised.