Highlights: Saltmarsh remnants and largest area of transitional habitats on the island
Access: View from the road
Perrys Guide: 2 B5,C5 & 20 B1,C1
View over the saltmarsh
Aerial Photo
Aerial view
Nature Reserves

Colin Best Nature Reserve

Leased to La Société Guernesiaise by the Best family in 2002, this is one of the largest nature reserves in Guernsey. It adjoins the La Claire Mare to the northeast and together they form the largest extent of salt-freshwater transitional habitats in the island.

The site is probably best known as the Old Aerodrome which was active between 1934 and 1939.

There are several different habitats on the site, which means the diversity of fauna and flora is high. The main habitats are:
  1. Saltmarsh
  2. Reedbed
  3. Coastal and semi-improved grassland
  4. Fresh-water temporary ponds
  5. Gorse scrub on the small hougue (hill)
  6. Brackish douits (ditches)

This is the rarest and the smallest habitat. It has been encouraged by keeping the drainage sluices partially open, thus allowing seawater to enter under the shingle bank to the north at high tides, flooding the lowest areas of land. The salt-marsh conditions have been colonised by rare plants, including glassworts, Annual Sea-Blite, Sea Spurrey and various rare insects. The area is visited by many different waterbirds, including Shelduck, Little Ringed Plover, Greenshank and occasional scarece migrants / rarities such as Pectoral Sandpiper and Buff-breasted Sandpiper.

The Saltmarsh
The saltmarsh
Purple Glasswort, Salicornia ramosissima
Annual Sea-Blite, Suaeda maritima
Greenshank, Tringa nebularia

There is a sizeable reedbed in the northeastern part of the reserve, which is contiguous with another area at La Claire Mare. It is an important breeding habitat for birds such as Reed Warblers, and for other passage migrants in spring and autumn. Many insects and other invertebrates are also found within the reeds, providing food for birds. There is also a patch of the very rare Adder's Tongue, known at only two other sites in the island.

Ophioglossum Reed Warbler
Adder's Tongue, Ophioglossum vulgatum Reed Warbler, Acrocephalus scirpaceus, about to be ringed on the Colin Best Nature Reserve
The majority of the reserve is covered in grassland. Coastal grassland, characteristic of peaty soil on the coast of Guernsey, occurs in the areas nearest the sea and as you move inland the species present are characteristic of semi-improved grassland. Much of the grassland is grazed and used for hay by a local farmer and no artificial chemicals have been used since La Société took over management of the site. This has meant that already the diversity of flowering plants has increased, and more Loose-flowered Orchids are seen each year, as well as other plants including Yellow Bartsia, Chamomile, Ragged Robin and Meadow Buttercup, which are sensitive to intensive agricultural methods. In the autumn, several species of brightly coloured Waxcap fungi can be found in some of the short turf. In August the inland grassland is the site for the West Show, one of Guernsey's Agricultural Shows.

Yellow Bartsia Chamomile
Yellow Bartsia, Parentucellia viscosa, in the semi-improved grassland Chamomile, Chamaemelium nobile, in the coastal grassland
wax cup fungus  
The wax cap fungus Hygrocybe conica, in the coastal grassland  
Fresh-water temporary ponds
Much of the reserve is very low lying and in winter temporary ponds form in several places. These are very attractive to birds. Two of these ponds have been slightly deepened so that the water last longer into the summer. It is hoped to put a bird hide next to one of these in 2007.

Gorse Scrub

This is increasing on the hougue. In the past this was grazed by sheep and was a fairly open habitat with dotted Gorse bushes. Now the hill is almost completely closed over. We hope to keep open a path across the centre. Scrub has its own value as a shelter for bird and small mammals, and the invertebrates that feed them. This patch is limited to the east by a track, but it would be undesirable for it to spread to the grassland in other directions.

Brackish Douits

A rare and unusual habitat. Most of these dry out in the summer, but when wet provide a home for many insects and invertebrates. Large leeches may sometimes be found. Green algae, related to the seaweed called Gutweed on the upper shore, grow in some stretches.


The Reserve is not generally open to the public but most of it can be observed from the roads around it or from the track that enters from the coast road in the north and goes past the Hougue. If you wish to enter the reserve please contact La Société Guernesiaise.

The Geese you will see are feral geese from a pair originally dumped here in the past. The large colony is now a threat to habitats, native plant and bird species, so steps are being taken to remove them from the reserve.

  Copyright © La Société Guernesiaise 2011. All rights reserved.
Candie Gardens, St Peter Port, Guernsey GY1 1UG, Channel Islands.