SITES

	Greatham, Teesside, UK
	West Site, Billingham, UK
	Grimsby, Humberside, UK
	Calais, France
Habitats on Calais Site Invertebrates Birds Biodiversity Management
	Huelva, Spain
	Scarlino, Italy
	Teluk Kalung, Malaysia
	Umbogintwini, South Africa
	Lake Charles, USA
	Burnie, Tasmania

Index by Category

Appendices

References

Calais, France

Habitats on Calais Site

A number of natural and semi-natural habitats are represented on the Calais site
(see Figure 15):

• Sand dunes and associated sea buckthorn scrub.
• Planted poplar copses, often associated with buckthorn thickets.
• Planted perimeter trees dominated by poplars.
• Created and grassed “dunes”.
• Open sandy habitats with naturally re-generating vegetation.
• Production plant and buildings.

Sand Dunes and Sea Buckthorn Scrub
In the past the sand dune system along the north coast of France was very extensive, stretching west towards the Alantic and east to the Belgium border and beyond. These once extensive dune habitats have now decreased under development or have been ecologically degraded to varying degrees by over exploitation. Large industrial complexes and port related activities have been established, especially around Boulogne, Calais and Dunkirk. The large cross-channel hovercraft port is located a few hundred metres to the north of the Tioxide site and the docking areas for numerous Channel car ferries are close by.

All of these developments have been built to some extent on former sand dune habitat, as indeed has the Tioxide production plant. In various locations along the coast some examples of the original sand dune ecosystem have been conserved as in the reserve of La Dune Machand immediately to the east of Dunkerque. The ecology of reserves such as this are good indicators of what would have been present on sites that have now been lost to development.

Sea buckthorn (Hippophae rhamnoides) is the only shrub that is especially characteristic of sand dune habitats where, in continental Europe, it often grows in association with wild privet (Ligustrum vulgare) to form dense thickets (Chapman 1964).

Although sea buckthorn is protected under EC legislation as an important component of the natural dune ecosystem it is nevertheless very invasive. Where it is not grazed e.g. by Rabbits, it can encroach into dune grassland with adverse effects on the botanical biodiversity of these areas. Also excessive stands of sea buckthorn can desiccate dune slacks resulting in a loss of marshland plants (Ranwell 1972).

Considerable areas of sea buckthorn together with associated wild privet are found on the Tioxide site, especially towards the eastern end (see Figure 15). In places the buckthorn forms virtually impenetrable thickets that are of considerable importance for birds (see Section Birds). Notwithstanding these dense growths of buckthorn there does not yet appear to be a problem. There is ample evidence of a healthy Rabbit population on the site which should keep the buckthorn in check. Nevertheless the situation needs to be monitored and appropriate management measures taken if the sea buckthorn becomes too dominant. Sea buckthorn management however, needs to be carefully planned and the process authorised by the appropriate authorities, since as previously stated the plant is a protected species. In the past Tioxide had to re-create buckthorn scrub in mitigation when some of this habitat was removed for an essential development on the site.

At the edges of the buckthorn thickets and towards the site boundaries other trees and shrubs, such as poplars (Populus spp.), elder (Sambucus nigra) and dog rose (Rosa canina) grow in association with the thorn scrub.

Planted Poplars
There are a number of areas of poplars on the site, especially in the south and south-eastern sections where mature trees occur. Some of these trees have been purposely planted and include white poplar (Populus alba), a species that is often planted on sand coasts (Mitchell 1974).

On the Tioxide site the poplar plantations are now self-generating and are growing in association with sea buckthorn, elder and dog rose. The ground flora in the copse areas is not especially diverse. Ground ivy (Glechoma hederacea) is common in some sections with stinging nettle (Urtica dioica) and white dead nettle (Lamium album) locally abundant. There are numerous patches of bramble (Rubus sp.) and some vetches (Vicia spp.) and red campion (Silene dioica).

A number of interesting insect species are found in this small woodland area
(see Section Invertebrates) and undoubtedly will be recorded when further surveys are carried out. The copses also provide nesting, feeding and roosting sites for birds (see Section Birds).

Perimeter Trees
Around most of the site a linear plantation of trees has been established. These are primarily poplars but in places there are also some sycamore (Acer pseudoplatanus), with some cypress along the western border. This linear tree screen would appear to have limited ecological interest although individual trees were used by birds such as Dunnock, Chiffchaff and Black Redstart.

Created Dunes
The main coastal highway passes the Tioxide site immediately adjacent to the northern boundary of the Huntsman property. This is an elevated roadway and much of the site is visible to passing traffic. As part of the site’s landscaping programme a number of “dunes” have been constructed. These dunes have been seeded and are quite successful in screening the site and improving the view from the highway, however, at present they have low ecological or biodiversity interest. A commercial grass mix has been use to seed the dunes that included such species as cock’sfoot (Dactylis glomerata), false oat grass (Arrhenatherum elatius) and Yorkshire fog (Holcus lanatus). Whilst some herbs such as white campion (Silene alba) and large bird’s-foot trefoil (Lotus corniculatus var. sativus) have been included the botanical diversity is low and none of the sand dune species characteristic of the Channel Coast were found during a brief visit in June 2001. By way of contrast a relict area of natural dune habitat near the eastern section of the site held the characteristic sea buckthorn thickets, areas of marram grass (Ammophila arenaria) and plants such as sea spurge (Euphorbia paralias) and common storksbill (Erodium cicutarium).

The low diversity grassland does not attract the diversity of birds associated with either the more open less vegetated parts of the site or the buckthorn dominated dunes (see Section Birds). Two birds of some European conservation concern however, do occur in this habitat. These are Skylark, that is present in low numbers, and more abundantly Meadow Pipit. The latter were watched displaying and almost certainly breed on the site.

Eventually sea buckthorn will invade these created dune areas and in some areas there is already evidence of this. In view of the rather dense grass sward however, it is doubtful if any of the more delicate and specialist sand dune species will colonise the area. Any additional dunes constructed in future could be planned to create a much more botanically diverse habitat that in turn would attract more varied and abundant animal populations (see Section Biodiversity Management).

Open Sandy Habitats
These habitats occur around the edges of the buckthorn thickets, in previously disturbed area sand on the sites of old, cleared production plant and related structures.

The vegetation in these areas is sparse with pioneering mosses and plants such as biting stonecrop (Sedum acre), common storksbill and sea spurge. Although the invertebrate populations of these sparsely vegetated habitats have not yet been studied in detail, the tiger beetle (Cicindela hybrida), a characteristic species of such habitats was found in July 2001.

Birds like White Wagtail also occur and flocks of feeding Linnets have been recorded. These open areas are also used by Crested Lark, a bird of some conservation concern in Europe (see Section Birds - Crested Lark).

Production Plant and Buildings
The man-made structures on the site obviously have very limited wildlife interest. Some common species such as Starlings and House Sparrows frequently breed in industrial structures and both of these are found in the built-up habitats on the Tioxide site. Two other birds the White Wagtail and the Black Redstart were also found in these man-made habitats. The Black Redstart is particularly associated with industrial sites (see Section Birds - Black Redstart).