AFTER welcoming the speaker, Karen Shelley-Jones, the chairman, Arthur Williams, drew members’ attention to the programme of visits being planned for the Spring and Summer.
Karen, an ecologist with the Peak District National Park, gave us a whistle stop tour of the great, but threatened biodiversity of The White Peak. Environmental degradation, poor biosecurity and pressure on resources continue to be of concern.
Karen’s talk reinforced a number of ecological themes (brown trout, butterfly conservation and trees) explored at recent Club meetings.
The geographical location of the White Peak, together with the limestone rich dales means that a number of plants are present at the geographical limits of their range and Sites of Special Scientific Interest abound. Plants of the deeply cut dales are a great treasure,which provide colour throughout the seasons. Cowslips, Mouse-ear hawk weed, Common rock rose, Kidney vetch (woundwort) and Mountain pansy and the rare Jacob’s ladder were described.
In 2002, Jacob’s ladder was voted the county flower of Derbyshire. Butterflies are often associated with particular species of food plants, Bird’s-foot trefoil being the food plant of the Dingy skipper butterfly. A great habitat for wild flowers is an old hay meadow, which is now very rarely found in the White Peak.
Up to 50 species of wild flowers and grasses have been recorded in such meadows, which need careful management to ensure plants are given time to produce seeds.
Birds with fine songs are another joy of the White Peak, Sky larks, in grasslands and the Twite at the moorland edges.
Unimproved, brown-looking grasslands, which often support multi-coloured wax cap fungi, are more interesting to the ecologist than an emerald green field.
A unique habitat, the lead rakes, (lead mine spoil heaps) provide conditions where the Spring sandwort, or Leadwort thrives.
Other plants cannot live in soils contaminated with heavy metals, such as cadmium, lead and zinc. Some other heavy metals are essential for plant growth, but these are required only in minute amounts.
Leadwort is a metallophyte which has chemical and physiological means to de-detoxify the lead absorbed through the roots of the plant. The Leadwort is thought to be able to compartmentalise the lead in cell vacuoles having first combined the lead with special peptides.
This insignificant plant is a very sophisticated miniature chemical factory.
It is a great pity that our Ash trees have not yet developed internal protective mechanisms to deal with the deadly Chalara fungus, which is yet another threat to our countryside.
Rivers and streams in the White Peak are of great importance to many species. Brown trout, Brook lamprey and Dipper are all important species found in our watercourses.
Here again all is not well. Apart from invasive plants, a very invasive alien creature, the Signal crayfish is causing mayhem in our waterways.
This highly mobile predator (up to 30cm long) escaped from farms and has all but destroyed the native population of the much smaller (12 cm long) White clawed crayfish.
The Signal crayfish also carries crayfish plague, a fungal disease, to which native crayfish have no resistance.
One of our members, Mike Gadsby, a well known local water bailiff, is a trained licensed trapper of the Signal crayfish.
A useful debate on the value, or otherwise, of controlling this damaging pest by trapping ensued.
It must be emphasised that any unlicensed activity in relation to any species of crayfish is strictly illegal.
Trapping the more mature specimens may give the juveniles the opportunity to develop more rapidly than otherwise would be the case.
However, the removal of even some of these voracious feeders who prey on fish eggs, larvae, nymphs and even fishing bait, must surely be of some benefit to other aquatic species and fishermen.
In addition to their insatiable appetites, the Signal crayfish dig one-metre length tunnels which destabilise river banks.
Conservation of the native crayfish is being undertaken in ark sites well away from any human activity, where biosecurity can be maintained
The red claws of the Signal crayfish certainly signal danger, not only to native crayfish, but to other species and the wider environment.
Club members were encouraged to visit the web site of the Peak District National Park to acquaint themselves with the priorities set for protection and conservation in the White Peak during the next few years. Club members wish the Authority well in its endeavours.
The next club meeting will be on 4th March when the subject will be ‘sustainable natural medicines and cosmetics’. New members and visitors are very welcome at our meetings.