Figure 1.Lifehistory ofA. sturioin the Gironde Estuarysystem.Majorpoints in thelifehistory arenumbered.ModifiedfromAnony-
mous(1995).
(Lepage &Rochard1995). In thepast, it wasfished
for its flesh(Benecke1986), mainly inthe southwest
region of thecountry(Laporte1853,Roule1922).
Sturgeon wereexploited in theGaronne and Dor-
dognerivers, in theGirondeEstuary, andadjacent
continentalshelfwaters(Letaconnoux1961).Caviar
fishingoccurredfrom1920 t o 1970(Castelnaud et al.
1991).Demand forcaviar increasedfishingpressure
on adultswhile thejuvenilescontinued to beexploit-
ed for flesh. Increasedfishingeffort, combinedwith
the impact ofdams andgravelextractionwhich limit
the reproduction bydecreasing theavailability of
spawninggrounds(Trouvery et al.1984,Rochard et
al. 1990),resulted in decline of the species.