Zooplankton
Under the surface of the water in the small freshwater wetlands there is an unbelievable diversity of life. There are hundreds and sometimes thousands of different species of animals and plants to be found there. Among the types of animals there, you can find insects, molluscs, worms, crustaceans, beetles and even fish – like sticklebacks, and tiny floating animals called zooplankton. Some of these animals like to live in the water column, some like to crawl about on the stems of the plants growing out of the bottom of the wetland and some others like to live their lives in the muddy substrate on the floor of the wetland.
There are many weird animals living in the wetlands, especially where there is standing water for most parts of the year. The common water flea, Daphnia pulex is a prolific inhabitant of our wetlands and lakes and its population explodes in May and June as they take advantage of warmer temperatures and the easier availability of food such as plankton and bits of organic matter floating in the water. However, and unfortunately for the poor old Daphnia, when their numbers increase sharply, other higher animals that like to eat daphnia (like carnivorous larvae, small fish, newts and small frogs) also increase in number and they keep the numbers of Daphnia in check.