Habitat Management, Principle 8: Maintain healthy natural wetlands and enhance artificial ones
Most cotton farms support a variety of natural and artificial wetlands, including streams, billabongs, floodplain swamps, storages and irrigation structures (ditches, drains, etc.). These wetlands offer a wide range of habitats for many waterbirds and other wetland fauna, and some provide essential filtration services, reducing the entry of sediment and chemicals to streams.
The key to managing wetland habitats is to ensure a variety of water depths, vegetation and edge types to optimise the diversity of birds and other fauna able to use them.
Deep water areas with little or no aquatic vegetation, no shallows and no surrounding trees for perching may support pelicans and a few species of ducks, but many other birds will avoid these wetlands. In contrast, a storage that includes deep and shallow areas, various floating and emergent aquatic plants, areas of exposed mud at low water level, and trees for perching may be inhabited by egrets, herons, spoonbills, rails, grebes, ducks, cormorants, swans and many more.
Similarly, well-vegetated storm-water drains and overflows will provide significantly better habitat for waterbirds than un-vegetated ones. Reeds, sedges and grasses in such areas also help slow down the flow of water, reducing erosion potential and trapping sediment and chemical residue.
- Maintain and improve wetland habitat quality
- Design habitat features for new artificial wetland areas
- Enhance existing artificial wetlands
- Ensure sufficient flow goes into natural wetlands to maintain vegetation and wildlife
- Protect natural swamps from grazing during critical periods (e.g. inundation, flowering, bird breeding)
- Include islands, shallowwater, mud-flats, and open water of varying depths in storages
- Leave standing and fallen dead trees in or around storages to provide perches for waterbirds (and hollows for some bush-birds to nest in)
- Leave or replace snags in billabongs and streams to provide submerged habitat for fish and other aquatic animals
- Plant or encourage the growth of aquatic vegetation, such as waterlilies, reeds and sedges, in and around the edges of storages and billabongs