Dune slack with ponds. In these hollows between the dunes the water table lies close to the surface.
Aberlady Bay Local Nature Reserve is an important breeding site for ground-nesting birds. Visitors between late March and late June should keep to the paths. No dogs are allowed.
Definition: linear depressions close to sea level in coastal dune systems
Between the ridges of coastal dune systems lie slacks. The floors of these sheltered depressions often lie close to the water table and so, unlike almost all other habitats within the dune system, water availability is not an issue for plants. In older slacks, the vegetation cover is almost complete and soil is starting to develop. Amongst the youngest dunes, the slacks are still flooded regularly by the sea, and so the slack floors show only pioneer vegetation below the trash lines and drift wood that line the slack margins.
The slacks at Aberlady show particular plant associations, with wild strawberries, buttercup and violets with some flag iris and willow in the slacks at the rear of the main dune system. The floor of the Marl Loch and the Yellow Mires rest on an old cockle bed, giving a calcium-rich pond and a calcium-loving community of wetland plants.