Mudflats - Ythan Estuary

The Ythan Estuary is located at Newburgh, Aberdeenshire, and contains intertidal mudflats within the estuarine system (fig.1). The Ythan Estuary is one of the least modified in Scotland and is the most extensive in the north east of Scotland, however it is one of Britain's smallest estuaries (NatureScot, n.d., NatureScot, 1984; Green & Bojar, 2009). Despite this, it regularly supports over 20,000 individual waterbirds through the breeding season, on passage/migration, and over winter. This is particularly because of the mudflats present (fig. 2) which provide an important food source and roosting site. The Ythan Estuary supports an internationally important population of wintering eider (Somateria mollissima), around 2% of the GB population, alongside nationally important populations of redshank (Tringa totanus) and lapwing (Vanellus vanellus). It also supports around 9% of the Eastern Greenland/Iceland/UK biogeographic population of pink-footed geese (Anser brachyrhynchus) (NatureScot, 2005b; NatureScot, 2020).

Impacts on Site & Site Management:
The estuary and intertidal mudflats have been used for a multitude of purposes, for example recreational activities such as angling, watersports, and wildfowling (NatureScot, n.d.; Reid, 2024). These do not appear to have a large-scale impact upon the mudflats. 

Pollution on the estuary has also been a problem. The River Ythan is 40km in length and the surrounding river catchment is 680km2 in size, with any pollutants from agriculture, industry, and urban areas making its way down-river into the estuary. A build-up of nutrients occurs, particularly nitrates and phosphates, and this causes rapid growth of algae which blankets the mudflats. This then has an impact on mud shrimp (Corophium volutator) abundance, which subsequently impacts waterbirds on the estuary as the mud shrimp is a key food source (NatureScot, n.d.; Reid, 2024). The Ythan Catchment was declared a Nitrate Vulnerable Zone in 2000, with work subsequently carried out to tackle catchment-wide pollution issues which would then benefit the river and estuarine systems.
 

Conservation Designations:
The  Ythan Estuary is covered by, or adjacent to, a number of conservation designations. 
– Forvie GCR
– Forvie NNR 
– Sands of Forvie SSSI (NatureScot, 1984)
– Sands of Forvie SAC (NatureScot, 2005a)
– Ythan Estuary, Sands of Forvie and Meikle Loch SPA (NatureScot, 2020)
– Ythan Estuary and Meikle Loch RAMSAR (NatureScot, 2005b)

 The Sands of Forvie SSSI has been designated for the estuary amongst other features such as saltmarsh, sand dunes, breeding bird assemblage and wildfowl assemblage. Many of the other designations cover the same or similar species, habitats, and assemblages (NatureScot, 1984; 2005a; 2005b; 2020).