This mosaic of habitats provides for numerous species from tiny insects to mammals and birds.
Osprey Lake is named after the ospreys that often visit the lake during the migration to and from Africa.
The osprey platform located on the island in the middle of the Osprey Lake is designed to encourage ospreys to stop here and possibly breed. Please note work is currently underway to get the platform back up by the spring migration.
Osprey Lake is one of the most sensitive areas of the park due to the amount of breeding and wintering birds that it supports.
In summer the surrounding reedbed is home to breeding reed warblers, sedge warblers, whitethroats and reed buntings.
The lake edges and island also provide nesting habitat for wildfowl such as great crested grebes, coots and tufted ducks.
In summer a number of birds migrate to the UK from Africa to breed – many of these can be seen in the park such as reed and sedge warblers, house martins, swallows, common terns and hobbies.
In winter a different set of birds migrate to the UK from more northerly places such as Scandinavia, Iceland and Siberia. Ducks such as shoveler, gadwall, wigeon and goldeneye all visit the park to spend the winter here.
In spring our summer migratory birds arrive such as reed warblers and swallows. They then leave in autumn. At the same time, our winter migratory birds such as wigeon and goldeneye begin to arrive and will leave the following spring.
The three lakes in the eastern end of the park (Osprey, Riverside and Kings Lakes) are all old gravel pits. Since extraction ceased they have been allowed to revert back to nature, producing the wonderful habitats we see today.
The nature reserve part of the park comprises the lakes, River Mimram and surrounding habitats.
The River Mimram is one of Hertfordshire’s best chalk streams and supports a wealth of different species. Chalk streams are a very rare habitat globally – there are only 180 in the entire world of which southern England has 90%.
Chalk streams are fed by water from underground chalk aquifers that bubbles up through springs. The water in chalk streams is therefore very pure and stays at a constant temperature of around 10°c.
Water voles, Britain’s fastest declining mammal, are known to be present in the park and otters are also likely to use the park.
Buzzards, red kites and kestrels can all be regularly seen in the park.
A number of bat species live, breed and forage within the park. These include common and soprano pipistrelle, Daubenton’s, noctule and serotine bats.
Kingfishers can be regularly seen flying along the River Mimram. Often their high pitched piping call gives them away before a flash of blue streaks past.
18 species of dragonfly and damselfly can be found in the park. Species include emperor, ruddy darter and black tailed skimmer dragonflies and common blue, banded demoiselle and blue-tailed damselflies.
The habitat to the east of Osprey Lake contains several pools dug to create further habitat for dragonflies and damselflies.
In spring Lady Hughes’ Wood is carpeted with bluebells.
The park also supports a range of butterfly species from speckled woods, brimstones and orange tips to meadow browns, red admirals and small tortoiseshells.
The rare purple emperor butterfly has also been found in the park.
Mimram - Jewel of Hertfordshires rivers
Bob Reed, a Herts and Middlesex Wildlife Trust volunteer, has produced this fantastic video which highlights many of the unique characteristics of chalk streams. Much of this was filmed on the Mimram at the chalk river section that Tarmac created at Panshanger Park as part of the quarry restoration works.
The long-term management approach of the partnership between Tarmac and Herts and Middlesex Wildlife Trust ensures the highest quality stewardship of the park's unique landscapes, heritage and natural features. Chalk streams are rarer than rainforests – there are only 185 chalk rivers in the world – so it's of the utmost importance to keep the River Mimram and the wildlife it supports in tip-top condition!