Illustrated talk by Lindsey Rendle, Planning Ecologist, Carmarthenshire County Council.

The talk by Lindsay Rendle, Planning Ecologist with CCC, revealed how difficult it is sometimes to reconcile the needs of wildlife (especially where there is a population or species of international importance or concern), with our desire for development. Her talk led to a lively response with many questions.

Lindsay referred in her title to the “butterfly effect” whereby, according to ‘Chaos Theory’, a minute change in the initial condition of a complex system can lead to a radically different and unexpected outcome. Researcher Edward Lorenz was using a computer model to predict weather found that one input value expressed to six decimal points gave a completely different result when corrected to three decimal places. In the light of such sensitivity a colleague posed the question “does the flap of a butterfly’s wing in Brazil set off a tornado in Texas?”

What we loosely refer to as “planning” is more correctly a land‐use planning system. It is a reminder that land supply is finite and should be shared equitably both between man and with other forms of life: we ask it to accommodate agriculture, industry, construction, transport and leisure activities, to yield fuel and raw materials and provide water storage and purification. It is also expected to deliver less tangible qualities such as aesthetic appeal, tranquility and inspiration while giving communities a sense of place.

It is a tall order to deal all the cards fairly but, hopefully, with a concerned and knowledgeable public as advocates and impartial ecologists on board, the planning system should ensure that wildlife is not always the loser when development takes place. Lindsey showed proposals for designating a Marsh Fritillary Landscape Conservation Area in the Mynydd Mawr area.

Now, returning to Chaos Theory and butterflies, it is difficult not to comment on the past year’s weather. After an exceptionally cold December we had a promising spring with early butterflies on the wing in good numbers and during the walk at Capel Dewi, the owners said they had observed 40? Marsh Fritillaries. Later it was wet and butterflies (including, mercifully, Cabbage Whites) nowhere to be seen. Autumn weather improved and was unseasonably mild: we took our hay crop late in September, there was a flush of dragonflies in October and we had Cowslips flowering at the beginning of November which were still in flower in February. Could the cause just have been the flap of a marsh fritillary’s wing in Cross Hands?

Notes and reflections by Andrew Stevens