Tuesday 8 May 2012

Inspiration through Ecology


Simon Davey studying lichens in Jersey
Life on Earth is a near infinite mix of species with complex inter relationships. It is quite incredible how every group of animals and plants has evolved in a way that also gives the naturalist a perfect avenue of study and development of knowledge. Take birds, for instance. An embryo birder would have little difficulty in distinguishing a robin, a blue tit and a blackbird in the garden. As his experience develops, challenges such as leaf warblers and waders present themselves to give a puzzle equal to any Times crossword.

Lichenologists in a Dutch churchyard
Personally, one of my greatest interests is in lichens. I suppose many would be put off lichens believing them to be far too complicated to get into. However, the ecological value of lichens makes them a challenge that is so worthwhile. Anyone with experience of suburban areas, and with even the slightest observation of the natural world, cannot fail to have noticed the scrambled egg like crusts growing on asbestos garage roofs, walls, or the enriched dog-pee zone at the base of trees in urban parks.
Xanthoria parietina


This is the lichen Xanthoria parietina. With something like 1800 species in Britain, lichens present a challenge that could keep any naturalist inspired and occupied for a lifetime. As with birds, some are easily identified, while the identification procedures to name others require a series of complex processes involving chemicals, high power microscopes and the accurate measurement of structures such as spores.  Lichens are probably the fussiest group about the environment in which they can survive. The presence or absence of many allows an ecologist to make a rapid initial evaluation of the health and ecological importance of a site. It is well known that lichens cannot tolerate acid rain. It was probably lichens that caused environmentalists to take seriously the problems, to us all, of industrial air pollution more than anything else. A few groups of species, and especially lichens, beetles and hoverflies indicate by their presence or absence the ecological continuity and lack of negative disturbance in the places in which they live.



Mothing in Beckley Wood, East Sussex
Species should be the basic vocabulary of the ecologist. Without knowing the species and the relationships between them, an accurate evaluation of the importance and health of a site is impossible. The importance of the species that make up the biology of a site is not always recognised by the ecological profession. Even when species are reckoned important, many professional ecologists are specialists in one group only. Ideally, ecological evaluation, to be done properly requires a general knowledge of a range of groups. 

Some years ago I was given a contract to look at the lichens of an important nature reserve. Lichens require light as they prosper through the photosynthetic ability of the algal partner. The dense woodland in much of Britain is unsuitable for lichens, and it was only a restricted open part of the reserve that was important for lichens. Much of the reserve had a dense understorey dominated by holly and regeneration, preventing totally the development of a lichen flora. The lichen lobby successfully suggested the removal of much of this dense understorey, stating that it would be beneficial to the important lichen flora of the reserve. The fact that of at least equal importance with the lichens were bats was not taken into account. A most important and rare bat species in the reserve requires a dense understorey to maintain a supply of milk for its babies. Without this, the air in the understorey become dry, and the bat mothers cease to lactate effectively. One of the most important aspects of lichens is that many of the scarcer species do not colonise into new areas rapidly. One theory about the dispersal and colonisation of lichens is that, in some of the scarcer species, this is done in the digestive tracks of molluscs. Mollusc slime is an ideal adhesive for the spores as they develop on new tree bark. However, the rate of dispersal by this method is very slow. No self respecting slug will ever cross a motorway to deliver lichen spores to another piece of woodland. It just won’t happen. Without a very considerable passage of time, the clearance of an area of understorey would have had no effect on the lichen flora whatsoever. In fact, the bats require open woodland suitable for lichens in which to forage. Once the bat and lichen conservationists started talking to one another, a perfect solution for one aspect of the conservation of the reserve was arrived at.

Birding in Scilly
Very recently, I have been made aware of Mark Telfer’s website about pan species listing. Basically, a pan species lister is one who takes a non specialist attitude towards the species he has seen, and can identify. Initially, this activity was thought to be somewhat anorak in its approach to natural history. However, this broad approach to species study allows for a greater understanding of the latticework of a site’s biological make up. One of the dangers of it, however is that a dedicated pan lister lays himself open to the charge of being a jack of all trades, and master of none. It came as an inspirational surprise to discover that there were others who embraced a broad approach to their study of species. Over the years, I have spent hours making typed lists, and latterly I list on my computer all species I have seen, either by being shown them, or by my own identification. Amongst other things, this has given me the greatest pleasure. It is such fun to see new species. Novelty is so often a dirty word, but if we are honest with ourselves, the pursuit of novelty is basic to human pleasure, at least to some degree.

I launched myself as a freelance ecologist in 1988. One of the aspects of my new, freelance life was tour leading, and this took me to many parts of the world. My pan listing activities unlike that of most of my pan listing colleagues have been global. In this blog, I hope to be able to share not only those British species I have seen across the board, but also those from the whole world. This will be a challenge, and I hope that looking at both my British, and world lists will give amusement to some, and inspiration to others, and especially the fellow pan listers on Mark Telfer’s website. Mark Telfer estimates that there are some 80,000 species that make up the life total for Britain. The highest score of any pan listers is just over 10,000 and my British score has just topped the 6300 mark. What a lifetime challenge this fact presents. The total for the world will run into millions. One problem that the pan lister can never suffer is boredom!  By keeping alert to the world around, the opportunities for being inspired by the natural world are ever-present.

Anyone who would like to make any comment, it would be really good to have your thoughts...

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