Introduction
Authors: Chauchat Claude 
Published: March 2010

When, in 1986, the Grotte du Bourrouilla at Arancou, Pyrénées-Atlantiques, was discovered, it was also found to have been excavated clandestinely. The sediments from these workings were wet sieved to produce an abundance of faunal remains and of bone, antler and lithic tools, as well as a few decorated pieces of bone and antler, which might be attributed to the Magdalenian. An extended test excavation outside the entrance to the cave gave evidence of three sets of stratified layers containing a sequence of occupation levels : a possible Azilian, an upper Magdalenian and a possible middle Magdalenian.
Radio carbon dating on bone from the test pit confirms that these levels relate to phases of middle and upper Magdalenian occupation and the results are comparable with those previously obtained for other sites in the Pyrenean region.
The tool assemblages from both the test pit and the clandestine excavations have been identified as belonging to the middle, late and final Magdalenian. The artifacts from the excavation have been classified, initially according to raw material and by typo-technological analysis and numerous refits have been found. The tool complex recovered in the spoil from the clandestine diggings reinforces the typological data of the test pit assemblages.
The range of antler and bone tools is varied and includes bone needles, double barbed harpoons, single and double bevelled points as well as an implement with a socket which may have been used for a haft. In the layers beneath the harpoon level there were forked bone points, typical of the Magdalenian in the Pyrenees. The most characteristic object is a small knife shaped, polished blade, made on a fragment of split rib, frequently decorated on the external surface of the bone. For ornament, deer incisors and canine teeth were sawn and drilled to make beads. The fragments left over from cutting cervid bone and antler indicate that artifacts were produced using a groove and splinter technique. Reindeer antler was used in preference to that of red deer, even though their bones were proportionately less abundant amongst thefaunal remains.
Twenty two of the objects recovered from the clandestine spoil bear more or less elaborate decoration or figurative engravings, some of which are very fine. On five of the pieces there are engravings of a number of animal species from different zoological taxons depicted in association with one another. All these figures are very small, occasionally no larger than a centimetre in height and some are extremely delicately detailed, in a style which has affinities with other objects from sites in the Pyrenees, Perigord or the Aveyron valley. The techniques employed by the engraver have been studied using an electron microscope, which has made it possible to trace the sequence of tool movements and the order in which lines were produced. The rich fauna (more than 3,000 taxonomically determined bones) includes fifteen herbivorous and carnivorous species. Red deer, reindeer and horse are the most abundant, followed by roe deer, wild boar and large bovids. Carnivores are also numerous, especially red and arctic fox. Also present are wolf, felids, bear and mustelids. The faunal association indicates a relatively cold climate and a composite landscape of forest and open prairie steppe country. The consistent absence of certain skeletal elements, the vertebral column for example, suggests that
Herbivores were butchered prior to being brought to the cave. The proposition that trapping was carried on in the vicinity of the cave is borne out by the abundance of carnivorous species.
Bird bones came mainly from the clandestine spoil and supply further evidence of the trapping capabilities of the Magdalenian hunters as well as of the richness of the environment. The identified species are from marsh, woodland and grassland habitats and small passerines are represented as well as some larger species of waterfowl and game birds. The migratory species give mixed seasonal indications, with a
number of Summer visitors but also some wildfowl present during the Winter. Numerically, snowy owl bones dominate over those of all other species from the spoil, a feature which has affinities with a number of other late Magdalenian sites. Microfaunal remains are also numerous and indicate that the environment was cold but not quite periglacial.
Fishes are also present, almost exclusively in the clandestine spoil and are mainly salmonids and pike. Examination of the vertebrae shows that most were caught during the Summer, indicating the presence of man at that season. A study of thin sections taken from the molars of the Herbivores demonstrates a similar trend, although there is evidence that a minority of these died during the Winter months.
Some human fragments, found in the clandestine spoil, may belong to Neolithic burials, similar to those which occur in other caves in the region.
The results of this first phase of study in the Grotte du Bourrouilla are put into the regional context and compared to other sites in the
western Pyrenees.