WildBristol.uk - Discovering Wildlife in Bristol

Description

Areas: Avon Gorge = 155.4 Ha / 384 acre, Leigh Woods = 198.3 Ha / 490 acre (2square km), Clifton Downs = 82 Ha / 202 acre, Durdham Downs = 162 Ha / 400 acre (1.6km squared). All together the area is 6 squared km (2.45km squared) or 600 Ha / 1476 acre.

Major area of scientific interest. lots of rare flora (over 30 rare plant species) and fauna can be found here which are nationally and globally rare with many endemic species which only exist in this area and no where else in the world for example a species of tree called the Whitebeam, otherwise known as "Sorbus" the most well known is the Bristol Whitebeam. All together there has been 21 Types (9 endemic (6 species, 3 Hybrids)) of Whitebeam (17 species, (13 native, 4 non-native), 4 Hybrids (3 native, 1 half native)) found in this area. Other rare plants include the Bristol rock cress, Bristol onion, otherwise known as "round-headed leek", Western spiked speedwell, Honewort, Autumn Squill, a single plant of Lesser meadow-rue, Hutchinsia, Bloody Crane's-bill, Little Robin, Rock Stonecrop, Fingered Sedge, Pale st John's Wort, Green-flowered Helleborine, Yellow birds nest Orchid, Bee Orchid, Fly Orchid and many more.

Leigh woods is home to rare mammals such as: Hazel Doormice, Greater and Lesser Horseshoe bats (very rare nationally), rare invertebrates e.g. Lesser stag beetle, Marbled white Butterfly, Silky wave Moth rare reptiles e.g. the Adder (Britain's only venomous snake, and the most Northerly viper in the world) as well as many rare birds the Bull Finch and marsh Tit. The Avon gorge is home to Peregrine falcons which made a return in 1995 after an absence of 20 years due to a dramatic decline in population from egg shell thinning caused by pesticides. After a ban of the pesticides causing eggshell thinning in raptors they've made a steady comeback. Other birds of prey can be seen including Common Buzzards, Kestrels, Sparrow Hawks, Hobby's darting around catching dragonfly's on the wing in the summer months, Merlins, Red kites, Tawny and Barn owls.

A pair of resident Cashmere Goats in the Goat Gully. There used to be 6 all together but two died of old age and the other two were chased off the cliff by dogs (which are not allowed off the lead inside the gully) in one of the cases the dog was killed. The goats are here for a very important job to eat away all the competitive scrub and Brambles allowing the rare flora to thrive. They were selected as they're diet only consists of woody materials They are native to Asia- China, Mongolia. Leaving soft vegetation unscathed.

The whole area consists of magnesium limestone. Which is a fairly rare soil type nationally. Due to steep sided cliffs holding heat, inside the gorge is on average, 1 degrees Celsius warmer year round than its surroundings. This creates a micro climate in which some plants at they're most northerly range can thrive.

Horseshoe bend. Devonian sandstone and Carboniferous limestone, overlain by with Triassic Dolomitic conglomerate. Designation as an SSSI is the presence of a population of the True Service-tree (Sorbus domestica) growing on the cliffs. This tree is nationally rare in Britain, and this site hosts the largest known population in England. Other notable species of Sorbus here are the Round-leaved Whitebeam (Sorbus eminens) and English Whitebeam (Sorbus anglica), both of which are also nationally rare in Britain. The nationally scarce Large-leaved Lime (Tilia platyphyllos) also occurs, and herbs include Field garlic (Allium oleraceum) and Pale St. John's-wort (Hypericum montanum). The saltmarsh vegetation, which lies at the base of the cliff, is predominantly made up of Sea Aster (Aster tripolium) and English Scurvygrass (Cochlearia anglica). There are however two nationally scarce vascular plant species here as well - Slender Hare's-ear (Bupleurum tenuissimum) and Long-stalked Orache (Atriplex longipes).

The tidal reaches of the River Avon provide habitat for waterbirds, with 64 species having been recorded up to 2004, including 21 species of shorebird, and 13 species of gull.