One of Britain’s largest estuaries, it supports abundant wildlife. Wildfowl occur in great numbers, while wading birds inhabit the mud of the foreshore and offshore.
In winter, Dunlin, Ringed and Grey Plover, Redshank, Knot and Black-tailed Godwit all feed on the mudflats at low tide. In May and August, passage waders such as Curlew, Sandpiper and Whimbrel occur.
The upper shore is clothed in saltmarsh with Cord-grass, Sea Plantain, Scurvy Grass and Sea Aster, there are also areas of common reed. Kingfishers are frequent here in winter and mixed flocks of finches may be seen feeding on the seeds of the saltmarsh plants.
These are important for wildlife and former clay pits on the Humber bank make up for some of the great wetlands of Lincolnshire lost through drainage. One such is the Far Ings nature reserve were the water is rich in microscopic life. This provides food for many invertebrates, which in turn support fish such as Eel, Roach, Rudd and Perch. Heron, Grebes and Kingfisher then prey on the fish.
Many duck – including Mallard, Pochard and Tufted Duck – nest on the islands and margins. In winter many more wildfowl live here, including Wigeon, Teal, Goldeneye and Gadwall, Goosander and occasionally Smew. Great Crested Grebe, little Grebe and Water Rail also nest.
The Humber Estuary is important for nature conservation and is designated as a Special Protection Area (SPA) under the European Birds Directive. It is also an internationally important wetland site under the Ramsar Convention.
The estuary itself has been identified as a Special Area of Conservation (SAC) under the Habitats Directive.
Sites designated under the Birds and Habitats Directives are collectively termed ‘Natura 2000’ sites. The directives, which are implemented in the UK principally through The Conservation of Habitats and Species Regulations 2010. These impose legal obligations on the UK government to protect the integrity and overall coherence of Natura 2000 sites.
Flood defence and habitat
Maintaining flood defences beside an estuary or the open coast can result in the loss of inter-tidal habitat. This can be either directly through the impact of maintenance or improvement works or indirectly due to the ‘coastal squeeze’ that will occur as sea levels rise if the defences are kept on their present alignment.
To compensate for these losses large areas of the estuary have been identified for coastal realignment. This is a process by which the flood defences are removed from their present position and the estuary is allowed to reclaim the land.