The glacier began to melt about 10,000 years ago and filled the holes in the land with water. Some of the water seeped away to form valleys and the rest formed the thousands of lakes that are found in the Border Country today. The lakes are an essential life support system for aquatic life and also land animals. With a lack of bacteria, algae, and plankton there is very little vegetation. This explains why the lakes are so clear.
Lakes hold an abundance of life in the water closest to shore.
This area is known as the littoral zone or the near-shore water. This area is favorable because the water is shallow and warm and contains more vegetation. In the littoral zone there are also down trees that have been left by beavers or the wind. These down trees provide protection and food for fish. The decaying trees also supply the lakes with nutrients and minerals important for the support of aquatic vegetation.