ponds

• pond bottom


  there is very little oxygen or light at the bottom of the pond. Decomposers and scavengers live here where they feed on dead material, eg water worms and rat-tailed maggots.
• mid water


  fish are the main predators here. Food is found on the pond bottom or the pond surface. Animals here breathe through their skin or gills, eg stickleback fish, water fleas and dragonfly nymphs.
• pond surface


   animals here breathe through their gills, skin or lungs. There is plenty of oxygen and light here. Animals found here include ducks, water boatmen, midge larvae and tadpoles.
• pond margin


  plants provide a sheltered habitat for insects and smalls animals such as frogs. There is lots of light and oxygen so plants such as marsh marigold thrive.
• above the pond surface


  birds such as kingfishers and insects like dragonflies are common here.