Even so, bog water is naturally low in nutrients, and many of the animals that live in the water depend on what comes in from the outside. The surface film of the water is like a web that tangles small unwary flying insects, and a bevy of small scavengers lie in wait for these windfalls. When prey arrives, it dashes across the water to capture it. A more obvious member of this scavenging fraternity are the shiny whirligigs that scoot over the surface - they are the most accomplished swimmers in the habitat. Other creatures inhabiting the surface film of bog pools are pond skaters, water measurers and water crickets.
Dragonflies are often the top predators in bog pools, which, due to their acidity, lack fish.
Many dragonflies are able to tolerate highly acidic conditions as larvae, favouring bog pools with Sphagnum. The dull brown nymph is fiercely carnivorous. It moults 12 times over a two to three year period before emerging from the pool as a young flying adult. In the water a range of mini-beasts occur including water scorpion, water louse, water spider, water beetle, caddis fly larva, mayfly larva, damselfly larva and water boatmen. Dragonflies lay their eggs in bog pools.