The cause of a fish die-off at Lake McConaughy, Nebraska's largest reservoir, remains inconclusive.

Fisheries biologists are investigating a die-off, in which around 1,000 dead fish were found on the west half of the reservoir.

Approximately 99 percent of the dead fish were adult white bass.

Pollution does not appear to be a factor, and water quality tests fall within normal ranges.

Lake users are encouraged to contact Game and Parks if they see live or stressed fish, as testing can only be done on live specimens.

Officials will continue to investigate.