Full lists detailing the records of all invertebrate species found during the survey are appended alphabetically.

Previous experience suggests that it is unlikely that more than 25% of the species present would be detected in one year by a single observer. It is assumed, therefore, that the total community of invertebrates is likely to be well in excess of 3,000 species. Marked in red are 36 species which either I consider to be indicator species of good woodland habitat or which are significant as being unrecorded previously in the county of Somerset (Watsonian Vice-counties 5 and 6) or in south Somerset (Vice-county 5) or are Red Data Book or Notable species. These records suggest that Nine Spnngs is an important reservoir for some species within the district and within the county. Some of the recorded species are declining nationally or are believed to be nationally scarce which also makes the site important on a national basis, if only for a few species.

Invertebrate Habitats

A more detailed examination of the site reveals the following aspects which are particularly significant to the invertebrate community.

a) The standard trees support a very high invertebrate community (much of which is not immediately obvious because of its height above ground level). It is likely that at least 500 species are supported by the living, standard trees. Some of these species are host-specific, others are present on a number of different tree species. The division of the wooded areas into woodland (with continuous canopy) and parkland (with discontinuous canopy) is particularly important since some species will be associated only with one or the other.

b) The (quite normal) dead wood associated with these trees, whether as dead patches on trunks, as dead branches or as completely dead trees, supports an important fauna. In recent years, this ‘saproxylic’ fauna has become one of the most important aspects of old woodland and parkland because of the reduction in quantity of the habitat, nationally, and the consequent fragmentation which has occurred. However, the saproxylic constituent of the fauna of Nine Springs is much poorer than had been anticipated. This results, almost certainly, from the extensive felling carried out in 1964. Documentary evidence suggests that virtually all the extensive dead wood habitat was removed at the same time. This resulted in a serious break in the continuity of the habitat at a time when it was already becoming difficult for re-colonisation to occur. Nevertheless, the survey has produced two beetles of dead wood previously unknown from Somerset in modern times (although one was present in the county in Neolithic times). In addition, several uncommon or local species of dead wood have also been identified. Standing dead wood is much more valuable in terms of saproxylic invertebrates than is lying dead wood (see below).

c) Medium vegetation with shrubs in open areas of woodland which are regularly exposed to a few hours of sun are important to many invertebrates. Four such areas are marked on the map (in green). . In addition, the two western ‘green’ areas also have sufficient grasses present to hold reasonable populations of Ringlet butterflies and all four areas attract and support butterflies on a regular basis. The two eastern ‘green’ areas contain a higher percentage of shrubs. The westernmost ‘green’ area has been grazed grassland until recent years and is still of some value as grassland habitat holding, for example, good quantities of bird’s-foot trefoil, yarrow, sorrel and speedwells. It is the only available habitat for some species of insect (such as Common Blue and Small Copper butterflies).

d) Medium vegetation in open areas with a high percentage of suitable nectar and pollen sources is both necessary for many of the woodland species and will also support many other invertebrates, both those resident within the Park and those which will visit as a result of normal itinerancy or migration. Plants which are important in this respect at Nine Springs are hogweed; great willowherb; meadowsweet; ragwort; creeping, spear and marsh thistles; figwort and angelica. The range of such plants is important because of differences in flowering periods. For example, hogweed flowers are mainly over before the meadowsweet flowers; angelica and ragwort will often flower into the autumn. Some species of invertebrates are attracted particularly to specific flowers (such as tree wasps to figwort). Areas which are presently important to invertebrates in this respect are marked on the map in red.

e) Short, flowery vegetation is also extremely useful. There is very little of this habitat at Nine Springs but there is an excellent small site on the east side of the main pond, containing dog-daisies, musk mallow, dark mullein, self-heal and other herbaceous plants which is used extensively by invertebrates and which, aesthetically, is also an attractive area.

f) Exposures of the Yeovil Sand are particularly useful for many fossorial (burrowing) insects such as species of solitary wasp and mining bee and are also a prime habitat for some species of beetle and bug. Such exposures are not frequent in the Park in open areas where the sun can reach them and some of the most important places for these are where trees have fallen, where cherry laurel has been cleared, and at the abraded edges of paths. Such exposures should be encouraged.

g) The northern ponds are of very low significance to invertebrates. The main reason for this is the very high population of large carp which have turned the environment into an eutrophic, algal soup. At least 60 of these fish were seen, together, on one occasion which suggests that there are considerably more than this in the pond. Most of these appeared to be of around four to six pound size. (I am told that the total number replaced in the pond was well over 600 and that several of these were over ten pounds in weight).The situation is compounded by the presence of a large number of waterfowl. The next pond to the south now contains perhaps 500 to 600 goldfish and related species and will, in due course, be in the same state as the main pond.

h) The areas of mud and silt in the shaded area at the south end of the main pond are of extreme importance. This area (marked in orange on the map) holds an incredibly high number of flies, many of which are common but a few of which are local to very rare. Not only is this area important to these insects but, because of their presence, it is also very important to birds, particularly Grey Wagtails and Moorhens at the pond level and many small insectivorous birds (warblers, tits, robins, etc.) in the adjacent vegetation. The main ponds are both heavily silted (the water in the subsidiary pond is only 10 to 20 cms deep over much of its area). The nationally rare fly Coenosia stigmatica which occurs in the silt area is probably a long-term resident of the Park and further investigations in this area are likely to reveal other important species.

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