resource

The presence of coarse woody debris augments habitat formation – backwaters etc. Streams that have been cleared of coarse woody debris / and or straightened / culverted will not be suitable for these species.

Species depend on the resorting of sediment during periods of high flow, whose frequency and severity usually peak in the winter away from montane areas. Sparsely vegetated, freshly deposited sediment is exploited for breeding as water levels fall in the spring. Some species can also occur on exposed coastal or lacustrine shingle or in artificially disturbed sites such as gravel pits, but only in the early stages of vegetational succession.

Also occurs on eroded sections of bank, especially in areas of slumped sand and clay. The sands are deposited in lower energy parts of the system, often at the downstream tail of gravel bars, or in backwaters.

The character, shape, size, location and sediment composition vary greatly, providing significant habitat diversity. This habitat is strongly associated with hydrological disturbance for both the formation of the sediment bars and for impeding vegetation colonisation (Bates et al. 2007). They are important habitats for many invertebrates and especially for beetles (Hammond 1998; Eyre et al. 2001) and flies (Drake et al. 2007).