Cliffe Pools

At the brackish Black Barn pools and grasslands, breeding lapwings and redshanks gather with dabbling ducks, marshland warblers, corn and reed buntings, linnets, stonechats and skylarks. The saline lagoons have breeding avocets and common terns, and a large breeding gull colony, now including Mediterranean gulls. Migrating waders such as greenshanks and spotted redshanks often make an appearance in the pools and lagoons.

The scrub which hugs many of the paths on the reserve supports numerous warbler species, owls and is one of the best places in the UK to hear nightingales. There is also an excellent display of blooming hawthorn from Pinnacle viewpoint.

At the brackish pools and saline lagoons, a superb range of returning migrant waders - 25-30 species seen in the last four years, including flocks of up to 5000 black tailed godwits and 3000 avocets, with green, wood, common and curlew sandpipers, little stints, spotted redshanks, greenshanks plus rarities. This builds up slowly through July and peaks in August, when it is as good as any site in the country in this respect. Large post-breeding flocks of up to 800 shelducks and 100 little grebes, and up to 60 feeding little egrets can be found around the pools.

In the scrub and grasslands, insects can be found foraging on the abundant plant life, including rare bumblebees such as the shrill carder, many butterflies including marbled white, Essex skipper and the migrant clouded yellow, and a large range of grasshopper and bush crickets, including Roesel's bush cricket. There is a good display of common flower species like wild carrot, birds-foot trefoil and melilot.

Migrant waders tend to diminish on the pools and lagoons at the end of September and are replaced by wintering waders such as dunlins and grey plovers. Summer songbirds head south whilst winter thrushes - redwings and fieldfares - move in from the north. It's a good time to seawatch on the Thames with skuas and sometimes petrels seen, especially in strong north-westerly winds.

In the scrub and grasslands, the last of the year's insects can be seen: late dragonflies include ruddy darters and migrant hawkers; there are late bush crickets, especially dark bush crickets; and the last of the year's butterflies include wall browns and small tortoiseshells.

Winter wader and duck numbers build up on the pools and lagoons, with impressive high-tide roosts of up to 7,000 dunlins, 2,000 lapwings, amongst other species such as redshanks and grey plovers. Wet winters can see up to 3,000 dabbling ducks (teals, wigeons, shovelers, mallards, gadwalls and pintails) mainly on the northern pools. Coots and diving ducks, e.g. pochards and tufted ducks, build up into the low hundreds with smaller numbers of goldeneyes. The occasional scaup or red-necked, black-necked or slavonian grebe may also make an appearance.

Hunting raptors in the scrub and grassland areas include hen and marsh harriers, merlins, peregrines and barn owls. Winter thrush and finch flocks make use of the abundant hawthorns.