Old Hall Marshes is a National Nature Reserve owned and run by the RSPB, part of the part of the Blackwater Estuary RSPB reserve.
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"Old Hall Marshes comprises extensive grazing marshes with brackish water fleets, reedbeds, saltmarsh and two off-shore islands. Breeding species here include avocet, lapwing, redshank, pochard, shoveler and bearded tit. During migration, marsh harriers, wheatears, whinchats and waders can also be seen, making this the perfect spot for avid birdwatchers."
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