Winterton Dunes - A Lichen Hotspot, but for how long?

 A 'Pathy' Problem - Lachlan Royle

Winterton Dunes 

Winterton dunes, pictured left is a site in East Norfolk that is recognised as a national nature reserve with over 100 hectares of land encapsulated within. It is a stunning place visually with rolling dunes speckled with dense patches of lichen and other plants and small pools that provide an ideal habitat for the rare natterjack toad. The dunes are also a valuable breeding site for the little tern in the summer months when it visits, with a 24 hour warden watch when the agile little birds arrive to breed at the largest colony in the UK. The dunes are rare as they are able to support acidic plants; such as lichens, whereas most of the rest of the Norfolk coastline is unable to, being far more calcareous. However as with many things at the moment the dunes are at risk due to human activity, despite clear signage asking visitors to stick firmly to the paths provided at Winterton dunes many visitors instead cut across the great expanse of dunes creating 'desire paths', these are negatively affecting the ability of many species to grow, for example Cladonia arbuscula and Cladonia portentosa. With summer now firmly on the horizon as well the dunes will be at risk of wildfires, much of the dunes is made up of dry xerophytic plants that would easily spread fire if one were not put out properly. Between 2020 and 2023 there have been 3 noticeable instances of wildfires on the dunes with one such instance in 2023 requiring 9 fire crews to respond.

Cladonia arbuscula 

Cladonia arbuscula is one of the two most commonly occurring species of lichen at Winterton dunes alongside cladonia portentosa. It is very important in Norfolk as the habitat that it thrives in; acidic heaths and moors, are so very rare here. Worldwide it is a species in decline as they are associated with high quality environments. Being a lichen it plays a very important role in the ecosystem by being a source of nitrogen fixation and helping with soil formation on top of being a useful habitat for other organisms. Unfortunately with the increased treading of paths at Winterton dunes there is a chance this is affecting the Cladonia population here, on our field trip we conducted a survey in order to attempt to measure the effect of the paths on lichen coverage. Our method involved walking down a length of path and every 10 paces stopping and distributing a quadrat randomly 3 times on either side of the path, at distances of 0.5,1 and 1.5 metres respectively. Then counting the coverage of quadrat squares that were filled by Lichen species. We did this at twenty sites on a path running from North to South close to the sea line and then again on a path roughly 400 metres further inland to compare if their was any great difference perhaps caused by acidity of soil on top of wear from walkers. Further the idea of measuring on the left and right side of the paths, or rather the East and West sides was to see whether wind direction had any say on results. Whilst neither of these showed any particular trends their were obvious trends indicated in Lichen coverage and distance from the paths, at almost every site; 68/80 observed in fact, their was a greater Lichen coverage at the 1.5m distance than the 0.5m distance. Suggesting there is a correlation between footfall and a decrease in Lichen abundance.