Dordogne River Research Articles

Aurignacian Settlement Patterns in the Vézère Valley

Aurignacian Settlement Patterns in the Vézère Valley

Use of Radiotracking in France for Recent Studies Concerning the E.D.F. Fishways Program

Radiotracking studies have been carried out since 1985 on three species of migratory fish - Atlantic salmon (Salmo salar , sea trout (Salmo trutta trutta) , shad (Alosa alosa) - in relation to surveys carried out before and after the construction of fishways on Electricite de France dams. Three sites were investigated: — Poutes-Monistrol hydropower project on the Allier river: determination of the possibility for Salmon to reach the new fishlift entry located at the Poutes dam; the effect of Monistrol powerhouse discharge on migration was particularly analysed, — st-Laurent-des-eaux weir on the Loire river: determination of the projected fishway's characteristics for shad, — Mauzac.dam on the Dordogne river: determination of the attractivity, for shad and sea trout, of a new fishway located close to the powerhouse. American radiotracking equipment was used (Advanced Telemetry System and Smith Root) with frequency ranges 40-41 MHz and 48-49 MHz. Fishes were tagged with transmitters of various sizes implanted in the stomach. A total of 28 shad, 43 salmon and 18 sea trout were tagged. Various techniques of tracking have been employed according to each site and fish species: — for manual tracking (by foot, car, boat or plane), we employed various antennas: loop, adcock, whip or underwater. Precise location was made by biangulation or trian-gulation with receivers or by use of underwater antennas; — automatic tracking with graphic recorders was used for continuous observations.Transports upstream by truck have been tested. They give good results only under specifc conditions. The duration of studies varied from 2 months to 8 months. The accuracy of results is directly dependent on the number of personnel assigned to the study. Use of radiotracking to survey or to design fishways appears to be a lumbersome but irreplaceable technique for the obtention of results concerning fish behaviour.

Remarques sur la biologie et l'écologie de Stenasellus virei Dollfus (Crustacea Isopoda Asellota des eaux souterraines)

Recent observations indicate that a laying season seems to exist, in karstic as well as in phreatic populations. Nevertheless, a single female cannot lay each year, because the reproductive intermolt averages 15-16 months and is always followed by one (9-10 months) or several non-reproductive intermolts. So, the minimum laying rhythm of female St. virei is biennial. The cavernicolous population (St. v. virei) of the Padirac swallow-hole is not a relict, but a colony separated from the main settlement of the alluvial waters of the Dordogne river. On the contrary, it is possible to find, close to each other, karstic and phreatic populations which belong to different subspecies (St. v. hussoni and St. v. boui) and live independently.

Origine des sables de deux coupes de plages des environs de la pointe de La Coubre (Charente-Maritime) et leurs variations mineralogiques en fonction des conditions meteorologiques

Abstract Although qualitatively the sands from two sections on the beach in the vicinity of Coubre point on the west coast of France showed a homogeneous mineralogic composition, quantitatively there was considerable variation, which is considered a function of the action of the sea and meteorologic conditions (wind direction and velocity). The sands are composed of material supplied by the Garonne and Dordogne rivers.

A Human Fossil from the Dordogne Valley. 1

THE curtain which conceals the early history of our race is being in these last years lifted at frequent intervals to afford us glimpses into the distant past. Among the latest revelations are those by the Swiss explorer, M. Hauser, of a nearly complete human skeleton—not yet fully described—from a rock-shelter in the Vézère Valley, chinless, with the great orbits and retreating forehead characteristic of the Neanderthal type; and, those still more recently made by the well-known prehistorians the Abb's J. and A. Bouyssonie and M. L. Bardon during their excavation of a cave opening in the vale of a small tributary of the Dordogne river, in the commune of La Chapelle-aux-Saints, in the Correze. Their careful and scientifically conducted excavations had previously, in 1905, been rewarded by the discovery of numerous quartz and jasperoid flint implements, scrapers (racloirs) and lance-heads (pointes), with others rather better finished and suggestive of the Aurig-nacian, which, taken with the entire absence of ruder amygdaloid implements (coups de poing) and of all worked bone, fixes with precision the archæological horizon as Late Mousterian. The fauna associated with these industrial relics includes reindeer, horse (rare), badger, woolly rhinoceros, marmot, wolf, fox, sheep or goat, a large bovine, and birds, and is characteristic of the cold climate of that epoch, which corresponds, in geological terms, to the Middle Pleistocene.