Fair Isle Bird Observatory & Guesthouse

Grassland fungi

Nick J. Riddiford, Roy Watling and Ali Murfitt

Fair Isle is extraordinarily diverse in terms of fungi. A window was opened on this world when Roy Watling and the late Bobby Tulloch made a two-day visit in September 1985 (details in FIBO Annual Reports for 1985 & 1986) in which amongst other finds, they reported two species new to Britain. Nick Riddiford continued this study and confirmed the importance particularly of Ward Hill summit with three second UK records. Riddiford continues to monitor the fungi (and general ecology) of Ward Hill but focus latterly has fallen on waxcaps and their grassland allies. Grassland fungi are in serious decline across Britain and Europe in the face of modern agricultural practices – from ploughing to intensive use of agricultural chemicals – and by consequence these fungi have been elevated to European Red List status. Loss of unimproved grassland in Western Europe over the last 75 years is estimated at 90% and grassland fungi serve as indicators for this essential but grossly under-valued wildlife habitat. On Fair Isle, grassland fungi have been the subject of experimental research at Schoolton – whose croft supports a significant diversity of waxcaps and other fungi. The study describes the (unexpected) results of withdrawal of agricultural chemical fertilisers on the croft’s grassland fungi. Over a six year period the number of grassland fungi showed annual increments to a qualifying level for a site of “international importance” as put forward by European and British authors. The implications of the findings are discussed in relation to unimproved grassland loss, the threatened status of this group and their use as indicator species, the effects of agriculture and current thinking on recovery of this group after loss. The article also focuses on grassland fungi status and conservation in Scotland; and grassland fungi’s second-class citizenship when it comes to conservation management. There was a steady increase in waxcap diversity over the six year study. By year three of the study, the Schoolton site had reached national importance according to categories applied elsewhere. Towards the end of the study it had reached international significance both in terms of numbers and for the presence of several rarely recorded taxa, two of which, Spangle Waxcap Hygrocybe insipida and Oily Waxcap Hygrocybe quieta, are European Red List species. The study also took into account other threatened grassland fungi groups, notably the pink gills Entoloma and fairy clubs Clavariaceae. These were slower to respond. Nevertheless, the number of taxa more than tripled over the six years and included a series of rarely recorded species. Further details of this study can be found here.

The grassland fungi elsewhere on the isle have not been forgotten and knowledge of the group was considerably enhanced by an intensive survey in the first week of September 2011 by Ali Murfitt, a BTCV/NTS trainee under the tutelage of Professor Watling. This confirmed the importance, in particular, of the numerous areas of short sward sheep-walk along the coastline and throughout the hill-grazing north of the isle. Most areas of cropped grassland support a considerable range of waxcaps and other grassland fungi, even along roadside verges. These habitats have been spared agricultural improvement. The main fruiting period spans August to November, though a few can be found in other months as well. The autumn birdwatching fraternity cannot fail to be aware of the colourful waxcaps and curiously shaped corals, clubs and earth tongues which proliferate in September-October. Fair Isle is certainly a rich site for waxcaps and their allies from a visual, landscape point of view, but how many are aware of their status as icons of conservation under severe threat elsewhere?

The following list comprises all taxa of the grassland fungi indicator group, including variations. The tally so far comes to 31 waxcaps Hygrophoraceae, 34 pink-gills Entolomataceae, seven coral and club fungi Clavariaceae, six earth-tongues Geoglossaceae and the BAP species Microglossum olivaceum (Helotiaceae). The term 'study site' refers to taxa recorded during the research project at Schoolton.

Download a copy of the list here.

Hygrocybe (quieta) obrussea. © Nick Riddiford
Hygrocybe ceracea. © Nick Riddiford
Hygrocybe chlorophanus. © Nick Riddiford
Hygrocybe coccinea. © Camila V. Quinteros Peñafiel