Crater Lake
Aquatic
Food Web
Keystone Species: Daphinia, the water flea, is vital for the success of the ecosystem. They provide 62% of the mass of food consumed by all fish (CLi). The fish in Crater Lake eat whatever they can, but the ample amounts of water fleas make them the leading food source. It feeds on most types of algae including diatom.
Role of Predation in Crater Lake:
Other Predator-Prey Relationships:
Role of Predation in Crater Lake:
- Humans- Fish; Fishing is encouraged on Crater Lake. Since both types of fish, Kokanee Salmon and Rainbow Trout, aren't native to the lake, it is important that we keep their populations from escalating to quickly. The restricted nutrients in Crater Lake also help stabilize and maintain populations that are healthy for the lake.
- Fish- Water fleas; Water fleas are known for being an r-selected group of organisms. This means that when there are good conditions for reproducing, they take advantage of it. Within a matter of weeks, the population will exponentially increase until it gets too large and the phytoplankton base can no longer support it. Both types of fish act as population managers, but Kokanee Salmon are specifically known for their zooplankton eating habits.
Other Predator-Prey Relationships:
- Rainbow Trout---Lake Snails; this interesting relationship works in 2 ways. The Rainbow trout feed on the snails, and they make up about 10% of their diet(CLI). When Rainbow trout die, the snails act as decomposers and eat the decaying fish matter.
- Midge flies in their larvae state are called Bloodworms. These bloodworms feed on many different types of zooplankton, like Daphnia.
Energy Pyramid
Most energy or biomass pyramids follow the Productivity Scale. This scale states each level retains 10% of the energy from the previous level. (Cliffs)