The relentless hunt for the so-called "Tsar fish" and its precious eggs has acquired such huge proportions in post-Soviet Russia that the prehistoric creature, which outlived the dinosaurs, is being pushed to the edge of extinction.

Russia's wild capitalism and murky reforms of the 1990s dealt a severe blow to fisheries such as the one in Zelenga, a tiny, once-flourishing town in the Volga delta, where sturgeon come to spawn after maturing in the Caspian Sea. Two hours by boat from the regional capital Astrakhan, its dusty streets dotted mainly with decrepit wood huts look almost deserted.