Host shifts in fungi caused by climate change?

Understanding the factors that govern the occurrence and abundance of fungal species is critical to their conservation. Here, we show that the host range of a common species, Auricularia auricula-judae, has changed in the UK over the last 59 yr. Over this time, the species has shown altered phenology, with earlier appearance of fruit bodies and a longer fruiting period, consistent with a response to observed warming trends in climate. Coincidental with the change in fruiting time is an expansion of its host range. We discuss how sampling artefacts are unlikely to be responsible for these changes and instead suggest that climate change has altered the competitive balance between fungal species that inhabit dead wood. Changing temperature and rainfall regimes cause different germination rates, growth rates and combative ability of one species relative to another, and in the case of A. auricula-judae may have resulted in the ability to colonise a wider host range. Thus, fungal host range must be thought of as a dynamic concept when formulating conservation strategies.