Plankton

 

At the bottom of the food chain of a waterbody are algae and zooplankton. They are the forage for higher levels of life such as larvae and fry (baby fish). Plankton “eat” sunlight and chemicals and become the basic stuff that feeds everything else in the water. 

 
Zooplankton: Daphnia

Zooplankton: Daphnia

 

The trophic state of the waters, how full of nutrients they are, determines what and how much grows in them. The Kezar Lake watershed has low to medium fertility as evidenced by generally clear or very clear waters and modest levels of plankton, enough to support a lively fishery and wildlife community but not enough to be a blight

 
Phytoplankton: Metaphyton, a “Cotton Candy” like algae common in the Kezar Lake Watershed. (Photo:Betsy and Dick Enright)

Phytoplankton: Metaphyton, a “Cotton Candy” like algae common in the Kezar Lake Watershed. (Photo:Betsy and Dick Enright)

 

There has been concern in many lake communities about growth of noxious algae blooms, particularly types of cyanobacteria which are some of the oldest life forms on earth. They are bacteria that photosynthesize and are largely responsible for having oxygenated earth’s atmosphere over two billion years ago. Unfortunately, some of these algae also emit toxic chemicals that, if dense enough, can be dangerous. Pets that have waded in such dense blooms have, in rare instances, died and people sickened.

A dense Cyanobacteria Gloeotrichia bloom.

A dense Cyanobacteria Gloeotrichia bloom.

These algae are very common in low concentrations. High concentrations, however, result from nutrient dense, warm waters. KLWA has a program to monitor algal blooms to determine if they are a concern. Our generally clean, clear waters do not support such blooms. But if they do happen, it is usually in small shallow areas and most blooms are benign. But they are certainly not fun to swim in. So far there has been no indication of any problem blooms in the Kezar Lake Watershed.