Water: Regular tidal flushing with seawater will ensure an abundant supply of larvae (recruitment) to replenish macrobenthic populations and prevent encroachment of the tidal flats by vegetation (Jackson et al ., 2021). While some freshwater inflow can boost nutrient supply and input of organic matter (favouring biofilm formation and increasing benthic biomass), effluent discharges and sewage outfalls are best avoided, as these can promote prolific algal blooms on the flats, which reduces diversity and attractiveness of tidal flats to some shorebirds (see Estrella et al. , 2011; Besterman et al. , 2020). Wetter areas on tidal flats provide habitat for macroinvertebrates, hence feeding habitat for shorebirds, while drier areas with some vegetation provide nesting habitat for birds and drier open areas may provide roosting habitat. But requirements vary across species, for example the Spoon-billed Sandpiper Calidris pygmaea seems to have a specific requirement for sandier substrates with shallow pools (Spike Millington, pers. comm.).
Moving large quantities of sediment requires heavy machinery and skilled labour. Here, sediment is transported on a boat and is pumped through a pipeline to the target area. Location: Roggenplaat island, Oosterschelde, The Netherlands. [Credit: Edwin Paree].
Pipes can be used on land and water to bring sediment to where it is needed. Location: Roggenplaat Islands, Oosterschelde, The Netherlands. See the photo on the next page for the result. [Credit: Edwin Paree]. \
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