World Habitat Day
October 4, 2016
It’s World Habitat Day on Monday 3 October. We’re celebrating the rare habitats we have here in the South Downs National Park.
Chalk grassland
Chalk grassland is one of the richest habitats in western Europe, containing a great diversity of species. You can find up to 50 species per square metre!
This habitat has developed through centuries of sheep grazing on the shallow, free draining soils that cover the chalk. Once common over the South Downs, it now only covers an estimated four per cent of the National Park.
Mill Hill Local Nature Reserve is a good place to explore quality chalk grassland and see the butterflies that thrive there. The reserve is on the south west facing slope of the Adur Valley, just north of Shoreham-by-Sea. There are 29 species of butterfly recorded on this site.
Visit in May and you’ll find a yellow carpet of horseshoe vetch with Adonis blue butterflies flitting around the turf. The chalk grassland on Mill Hill is not only good for butterflies, but reptiles too. Keep your eyes peeled for the black adders!
Chalk streams 
There are only 200 chalk streams in the world and 160 of these are in the UK with the majority in southern England.
The River Meon and River Itchen in the South Downs National Park are fine examples of these rare streams, which are important for wildlife as well as for fishing.
It’s the combination of geology and climate that give chalk streams their distinctive clear water. The good quality water together with the gravels of the river bed, provide habitat for an abundance of insects which provide food for fish.
The well vegetated banks with plants such as watercress, give fish and other wildlife places to shelter from predators and forage for food. Our chalk streams are an important habitat for riverfly, brown trout, bullhead, otter, water vole, kingfisher and water shrew.
Heathland
Lowland heath is an internationally rare habitat. Heathers are the main type of plant, but you’ll also find birch, gorse, purple moor grass and scots pine. The UK has 20 per cent of the world’s total heathland habitat, though what we have left today is less than a fifth of what was here 200 years ago.
In the South Downs National Park heathland develops on the Lower Greensand to the north of the chalk downs. The plants have adapted to survive on poor soils and dry or waterlogged conditions. Our heaths support a variety of wildlife such as nightjar, Dartford warbler, smooth snake, sand lizards, silver studded blue butterflies and heath tiger beetles.
Visit Black Down, near Haslemere to see a fine heath and superb views across the National Park. At 280m it is the highest point in the South Downs National Park.
Woodland
South Downs is the most wooded National Park in England or Wales. Wander through the dappled light of the Hangar’s beech trees or the otherworldly yews of Kingley Vale and it is easy to forget that to thrive, woodlands need to be managed. Light needs to reach plants and flowers on the forest floor to ensure they can in turn support the animals which rely on them for habitats and food.