Potential impact of ash dieback on UK wildlife

3rd Feb 2014

A scientific report published today has explored what might happen if Chalara infection and associated ash dieback led to widespread death of nearly all ash trees within the UK. It reports that it is likely that there would be a high negative impact on some populations of plant and animal species that use ash trees for feeding/breeding or as a habitat.

The study, commissioned by the Joint Nature Conservation Committee (JNCC), has discovered that 1,058 species have an association with ash: 12 birds, 55 mammals, 78 vascular plants, 58 bryophytes (mosses, liverworts and hornworts), 68 fungi, 239 invertebrates, and 548 lichens. Of these, 44 (29 invertebrates, 11 fungi and 4 lichens) were found to only occur on ash trees, while a further 62 were described as ‘highly associated’ with ash and rarely found on other tree species.

Besides identifying at-risk species, the report gives a preliminary assessment of tree species that could provide an alternative host for plant and animal species associated with ash. Although none provide a close match, a number of native trees could provide a partial substitute, such as oak, alder and aspen. The study also looked at what tree species might be expected to replace lost ash, and the nature, scope and impact of resulting changes to ash woodlands. It gives a brief account of the effects of several possible management scenarios as examples of how woodland management could be used to help support biodiversity and ecosystem function.

Lead author Dr Ruth Mitchell, plant and soil ecologist at the James Hutton Institute, said: “The loss of ash trees would have significant consequences for those species that are highly dependent on ash.

“Ash trees have a unique set of characteristics, such as producing nutrient-rich highly degradable litter that does not form a deep litter layer and which maintains a high soil pH. The trees also cast a light shade. The nutrient cycling characteristics of ash and light penetration of the ash canopy contribute to the diversity of the associated ground flora.

“Our results show that some other tree species have characteristics similar to ash, but none match it entirely. If ash dieback-related mortality is high, the tree species that replace ash may not preserve these ecosystem characteristics.”

Report: The potential ecological impact of ash dieback in the UK. 2014. Mitchell, R.J., Bailey, S., Beaton, J.K., Bellamy, P.E., Brooker, R.W., Broome, A., Chetcuti, J., Eaton, S., Ellis, C.J., Farren, J., Gimona, A., Goldberg, E., Hall, J., Harmer, R., Hester, A.J., Hewison, R.L., Hodgetts, N.G., Hooper, R.J., Howe, L., Iason, G.R., Kerr, G., Littlewood, N.A., Morgan, V., Newey, S., Potts, J.M., Pozsgai, G., Ray, D., Sim, D.A., Stockan, J.A., Taylor, A.F.S. and Woodward, S.


Back to List »
Share |