The Isles of Scilly. Rosemary Parslow
from the site demonstrated the arctic tundra nature of the Devensian environment. Chaffweed Anagallis minima grows along some wet cart ruts across the heathland, but is easily overlooked. Turfy Hill may have got its name from the practice of cutting turf there formerly. Now the area is dominated by bracken communities, with smaller patches of heather and gorse. Small adder’s-tongue fern also occurs in this area, and one of the large species of New Zealand flax, Phormium colensoi, is well established and spreading.
Burnt Hill is the small promontory of open land on the north of the island between Turfy Hill and Chapel Down. It consists of mainly heather-dominated maritime heath and grassland. Inland from the promontory the heathland becomes dominated by bracken communities and a large area of gorse. Many areas of gorse and bracken are being managed to encourage the re-establishment of heathland plants. Chapel Down, where the land rises up towards the daymark, is dominated by waved heathland with scattered granite boulders and exposed granite platform very prominent towards the east. Many of the rare heathland plants, including small adder’s-tongue fern, orange bird’s-foot and chaffweed, are also found here, and this is also the territory of the St Martin’s ant Formica rufibarbis (see Chapter 14). There are steep cliffs around the edge of the headland with colonies of nesting seabirds during the summer. Above the cliffs are areas of bracken communities and gorse scrub. At Coldwind Pit near the coast there are a number of unusual aquatic plants growing in and around the pool.
On the north side of St Martin’s is an unusual open area called the Plains (Fig. 47). Formerly open grassland and low heath that had developed from dune grassland, it is becoming overgrown by gorse and scrub. Formerly small adder’s-tongue
FIG 47. North coast of St Martin’s, with the Plains and Round Island lighthouse in the distance. (Rosemary Parslow)
FIG 48. Mouse-ear hawkweed is one of the unusual species found in dune grassland on the Plains, St Martin’s. (Alma Hathway)
fern was widely distributed throughout the Plains until it became submerged by taller vegetation. Rare plants such as orange bird’s-foot and a patch of mouse-ear hawkweed Hieracium pilosella at its only known station in Scilly can be found here still (Fig. 48). Above the Plains among the dense thickets of common gorse it is also possible to find the strange pink nets of the parasitic heath dodder Cuscuta epithymum, another plant apparently only found in this one place in Scilly. The headlands and slopes along the northern side of St Martin’s also have spreading, triffid-like, populations of New Zealand flax, although control measures to reduce their numbers started in 2005. It is likely similar measures will be taken against another invasive alien, Myrtus luma, a myrtle-like shrub. Nearer the coast the dune is still active and sea spurge and Portland spurge are among the plants growing on the edge. A sand bar joins St Martin’s to the small, uninhabited White Island (see Chapter 7).
ST AGNES AND GUGH
Officially counted as one island, you could be forgiven for considering them two separate islands if you only saw them at high tide, when the sea covers the sand bar that links them. Most days there is a period when the bar is uncovered and it is possible to cross from Gugh to St Agnes. When the Hick family lived on Gugh in the 1970s, if the bar was covered by the sea, their two sons would sometimes have to row across in their small dingy – the Bar Bus – or miss getting to school on St Agnes if it was too rough to row (W. Hick, in litt.).
St Agnes is 1.5km long by about 1km wide, and Gugh 1km long by about 0.5km across. The land area they cover together is 145 hectares, of which Gugh is 37 hectares. The St Agnes coastline is very convoluted, so walking around the edge can take a suprising amount of time. In the days of the St Agnes Bird Observatory the daily round of the perimeter of the island, to check what birds had arrived overnight, was said to be five miles (8km), presumably including Gugh.
St Agnes
Most of what could be called the ‘middle’ of St Agnes is cultivated, mainly as bulb or arable fields, and it includes the three ‘towns’, Higher, Middle and Lower Town. Inland, St Agnes is a made up of a nucleus of small fields, farms and houses. Many of the fields have a good arable weed flora and between hedges are glimpses of delightful gardens full of exotic plants. Some of the garden walls have some of the best collections of lanceolate spleenwort Asplenium obovatum in the islands.
Wherever you are on St Agnes you are aware of the lighthouse perched on the hill in the middle of the island. The fat white tower dominates the landscape and appears to squeeze into every photograph (Fig. 49). St Agnes lighthouse was built in 1680, making it one of the oldest in Britain. Initially the light was supplied by a cresset, a coal-burning brazier, which stood on a platform in the lantern. This was not very efficient and was replaced by copper oil lamps and revolving reflectors in 1790. The wind vane on top of the lantern is 22.5 metres above the ground, 42 metres above mean high water mark (Bowley, 1990). When the Peninnis Head lighthouse came on line in 1911 the St Agnes light was downgraded to a daymark. The lighthouse keeper’s house is now a farmhouse. Just below the lighthouse hill is the former parsonage in a grove of trees. In migration times a constant stream of birdwatchers patrol the road outside the parsonage in the hope of seeing some really unusual bird that has been attracted to the dense cover in the garden (Fig. 50). Quite often, if they are lucky enough to glimpse a Pallas’s warbler Phylloscopus proregulus or some such rarity, it will flit across the road to disappear out of sight behind the massive wall of the lighthouse garden.
The northern part of the island is flat, low-lying and sandy, with a large meadow and a few former hayfields towards the rocky headland of Browarth. From the hill near the lighthouse you can see the almost perfect circle of Big
FIG 49. St Agnes: cattle grazing beside the lighthouse, May 2005. (Rosemary Parslow)
FIG 50. Pied flycatcher near St Agnes lighthouse. The gardens of the parsonage and the lighthouse attract many passage migrants. (D. I. M. Wallace)
Pool in the meadow (Fig. 51). Both the pools here (there is also a Little Pool nearby) are surrounded by grassland on low-lying land with the sea on two sides. The sea occasionally floods the meadow area, although recent sea defences have reduced the frequency. At other times the pools flood after heavy rain and the leat connecting Big Pool to the sea has to be opened at low tide to release the water. So, although usually freshwater, Big Pool may at times be slightly brackish. Around the pools are successive rings of vegetation: sea club-rush succeeded by saltmarsh rush, marsh pennywort, then creeping bent Agrostis stolonifera. Big Pool contains a few aquatic species, usually fennel-leaved pondweed but on occasion beaked tasselweed. The pool attracts very few breeding waterfowl, but is important at migration times. There are two resident Odonata species, common darter dragonfly Sympetrum striolatum and blue-tailed damselfly Isnura elegans. Frequently there are very large common eels in the pool and occasionally a heron Ardea cinerea will be seen standing in the pool, struggling to swallow one that has wrapped itself around its neck. These drawn-out battles between fish and bird can last for many minutes before the heron manages to swallow the fish or gives up and lets it go.
The meadow is also the local cricket pitch (as well as the tennis court and occasional helipad, especially in winter), with a species list that includes a
FIG 51. Big Pool and the chamomile cricket pitch, St Agnes, February 2004. (Rosemary Parslow)
number of rare and unusual plants including autumn lady’s-tresses, chamomile and several rare clovers. Most