The extreme heat and lack of rain throughout Illinois are creating the right conditions for fish kills in ponds and backwater lakes.

The Illinois Department of Natural Resources says it is already responding to reports of fish kills from private pond owners.

The die-off of fish is caused by oxygen levels that decrease as a result of less rain and evaporation caused by high temperatures. Algal blooms also decrease oxygen levels.

The state agency says nearly all fish kills are the result of natural causes, not chemical contamination.

It says there is little that pond owners can do to prevent them.

But it does recommend that farmers and others handling chemicals or manure take care not to contaminate ponds and streams, especially after rain storms.