Macroinvertebrates, or waterbugs, are useful biological indicators for understanding waterway health as they can withstand different levels of pollution.
A huge variety live in our waterways, from dragonfly larvae (often called ‘mudeye’) to caddisfly larvae, diving beetles and waterboatman. Their habitats vary greatly, from open water to sediment and edges.
Many waterbugs depend on vegetation in a waterway for habitat. The loss of plants and erosion can threaten waterbugs and the food chains they support. Planting native vegetation on waterways and managing stormwater pollution helps to protect the waterbugs in our waterway.
Checking variety to understand a waterway
The following clip from Channel 11's science show, Scope, features Melbourne Water's Priya Crawford-Wilson at Darebin Creek, explaining the various types of waterbug and what they mean for waterway health.
Sensitivity to pollution
Because different macroinvertebrates can withstand different levels of pollution, they are useful biological indicators for understanding waterway health. A healthy waterway will have lots of different types of waterbugs.
|Pollution sensitivity||Macroinvertebrate examples||Waterway type and location examples|
|Very tolerant||Snails, flatworms, leechs, mosquito larvae||Highly disturbed streams, inner city, industrial areas|
|Tolerant||Freshwater shrimp, amphipod, dragonfly||Disturbed streams, suburban streams|
|Sensitive||Caddisfly, mayfly, diving beetle||Streams with little disturbance, well vegetated streams in farmland or low density housing|
|Very sensitive||Stonefly nymphs, dobsonfly larvae||Streams with good water quality and habitat, forested areas|