7. Invertebrates (other than insects)
With some notable exceptions, few members of this group have been studied in any detail on Portland. However, all the groups listed below will occur in Independent Quarry in time, indeed many probably already do.
The coverage of all invertebrate groups is summarised in Table 24 below.
7a. Flatworms
One species, Polycelis felina, is particularly abundant in several ponds on the island and will most likely colonies any permanent freshwater areas in the quarry.
7b. Snails
Calcareous grassland provides an abundance of the green material and minerals required by snails to build their shells and soft tissue. Disused quarries also provide abundant cover and damp areas that snails also require. It is not surprising then that Portland has an abundant and relatively well-studied population of slugs and snails. Ponds, streams and ditches also provide important habitats for snails and if successfully established in Independent Quarry could well add to the island list.
click here to view the list of Snail species that could colonize Independent Quarry in a new window
7c. Crustaceans
Away from the shore, the only crustaceans that live out of water in the UK are woodlice. Limestone quarry habitats, with their abundance of flat stones, provide many suitable areas for woodlice to live. Other types of crustaceans may also be able to colonize the pond. Most will be microscopic animals such as water fleas, for which I have been able to find no information about distribution on Portland. Consequently the table below deals with woodlice and one species of freshwater shrimp.
click here to view the list of Crustaceans that could colonize Independent Quarry in a new window
7d. Spiders
As with the previous group, limestone quarries provide spiders with many suitable hiding places. In addition, grassy areas are also home to many spiders This group is an important food source for larger organisms, particularly birds.
click here to view the list of Spiders that could colonize Independent Quarry in a new window
References for Section 7.
15. Green, G. (1978) A study of aquatic invertebrates from Culverwell and the Reedy Ditch, in Portland Bird Observatory Report for 1978.
17. Fleming, J. M. (2001) Land Snails at Portland in 2001, in Portland Bird Observatory Report for 2001.
18. Fleming, J. M. (2001) Woodlice at Portland in 2001, in Portland Bird Observatory Report for 2001.
19. Pembroke, I.P. (2003) Spiders on Portland, in Portland Bird Observatory Report for 2003.