The recent heat wave is being blamed for killing thousands of fish in several southern Minnesota lakes. Most of the lakes are shallow, and thus more susceptible to summer fish kills, and most of the fish were northern pike, which prefer cold water. Affected waters include a pair of lakes near Albert Lea where several thousand northerns have died in recent days. DNR officials in New Ulm report upwards of 15 affected lakes, but believe the fish populations will recover. Some waters around the Alexandria area have also seen recent fish kills.