The Sabalo Disaster The extraordinary growth of Santa Cruz has put strains on fish stocks already troubled by environmental problems. Bolivia is landlocked so relies almost totally on fresh water fish from lakes and rivers. The eastern lowland region or more than half the country sits between two of South America' s great river systems, the Amazon to the north and the Plate to the south and east. Santa Cruz itself is on an Amazon tributary the River Pirai and 370 kms by air to the south is the River Pilcomayo. Fishing in the Pirai has long been a problem due to the growth of the city and urban spread of towns in Andes mountain foothills upstream. The Pilcomayo was thought to be different and had been reckoned as a bottomless source of the Sabalo, [Prochilodus lineatus] a good quality food fish. The Sabalo is migratory and every year the riverside communities waited for the Sabalo to arrive in their tens of thousands. In old times the arrival of the Sabalo meant full stomachs for the Weenhayek [syn: as Wennhayek] an indigenous people [also known as 'Mataco' in Bolivia or Wichi in Argentina]. Then as Santa Cruz grew the arrival of the Sabalo meant a good trade and refrigerated and ice- laden trucks [lorries] lined up to carry the fish to market. In 2005 the Sabalo migration failed and the catch dropped from 1440 tonnes in 1986 to under 500 tonnes. The problems had been noticed earlier and alarm bells sounded. A three year close season has been called for but the problem could be deeper than overfishing.

In the Andes Mountains The Pilcomayo rises in the Andes mountains in a mining region where arsenic effluent from the refining processes has been released into headwater streams. Added to this problem the river downstream from Bolivia forms the border between Argentina and Paraguay where bi-national river control schemes with low dams may have altered the spawning grounds. And the conundrum confused even more by the suggestion that the 1990/1995 El Nino climate phenomenon may have affected the flow of the river. With less water, its discharge across riverine flood-plains has been reduced and upset the nursery grounds for the fish. Sediments from the high mountains are also said to be reducing the flow. The story is set to continue.

The Amazon to the north is a different tale - or is it?

In the 1980's with Technical Assistance from a British [United Kingdom] Fisheries scientist, Bolivia's fish resources were evaluated and plans made for catching, distribution and selling at clean markets. One market was established in Santa Cruz in part of the old city close to the first 'ring' road then marking the edge of the main urban area. The market still operates and is well liked for its fresh fish and open air grills. Prices are higher and some fish are not always available. The land north from the city leads directly to the Amazon river system where at one time fish were abundant. Some species were noted for their size such as the giant catfish the Surubi [Pseudoplatystoma coruscans]. Large specimens could reach 1m 70cm or more perhaps, and weigh up to 50 kilos, though many of the fish caught today are smaller and found far away from the river ports. Fishermen in Trinidad close to the Beni River some 370kms NE of Santa Cruz say they have to travel longer distances to find the fish and that adds to their cost. A good Surubi provides many filets of good flesh that sell in Santa Cruz market for the equivalent of 4.30 US dollars a kilo [2005]. To put this in perspective , a local schoolteacher earns about 50 US dollars a month while selling clothes in the market earns about 37. Many people eat sabalo as it is less expensive. But more environmental problems on the way. The year 2005 rates as a record for low water levels and drought across the region. The main Amazon river at Manaus in Brasil 1600 kms north of Santa Cruz was almost 2m below its normal level in October, a low point not seen for fifty years. Many of the smaller Amazon tributaries are reported drying or stagnant with fish dying and weed rotting. During the year the Beni region north of Santa Cruz experienced serious drought with a major fire in the tropical forest across a broad front after which the all the natural habitats will take time to recover. It may seem to be avoiding the issue of who or what is to blame for the changes but the truism that 'time will tell' is perhaps the best that can be said today.

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