River critters identified and cataloged

Biologists now have a comprehensive view of the ecosystems present in the Carson, Truckee and Upper Truckee river basins.

Scientists from the U.S. Geological Survey recently released a report identifying the species and numbers of algae, invertebrate and fish populations in the rivers. Samples were taken from 20 sites between 1993 and 1996.

"We collected lots and lots of bugs in the Carson and Truckee river systems to see how populations changed downstream," noted Ralph Seiler, co-author of the report.

"It's mainly of interest to biologists. If something happened (like a hazardous materials spill) they could see how the population changed."

For those interested in numbers -- but not too many -- the survey found 514 species of algae in the rivers. Most of the invertebrates identified belonged to the mayfly, stonefly or caddisfly groups.

Samples yielded 18 fish species, of which 12 are not native to the river basins, and one endemic crayfish specie.

Those interested in details of the survey -- including lots of names, numbers and charts -- can find the report at http://pubs.water.usgs.gov/ofr02012.