European Red List of Vascular Plants - European Commission

more than 16% of threatened species), an increase
in fire frequency or intensity (or sometimes also fire
suppression), severe weather events, such as drought and
flooding, and intensive forestry (including pollutants
from forestry activities).
Although Figure 17 shows intensified livestock farming
as the most widespread threat to CWR species, if the
proportion of threatened to non-threatened species is
considered, only 29% of CWR impacted by livestock
farming are assessed as threatened. The opposite is the case
for the impact of alien invasive species on CWR, where
66% of species impacted are threatened. This may lead to
the conclusion that in Europe alien invasive species are
a more pernicious threat to CWR species than livestock
farming; however, this result has to be interpreted with
care. Firstly, overall more threatened and Near Threatened
species are affected by intensified livestock farming (32
species) than by invasive species (21 species). Secondly,
many species are affected by more than one threat and it
might be a certain combination of threats that increases
the species’ risk of extinction. These potential cumulative
effects have not been analysed. Further, the Red List
assessments are only a measure of the threatened status of
species as entities (i.e., taxonomic diversity), not of intraspecific
diversity. Livestock farming and indeed many
of the other threats impacting CWR could be causing
significant levels of genetic erosion; however, without
regular and long-term monitoring of genetic diversity
within and between a broad range of CWR species, we
cannot make any supported assumptions.
Climate change is also a significant threatening factor
for CWR species. It is predicted to increase average
temperatures by 2–4°C over the next 50 years and cause
considerable changes in regional and seasonal patterns of
precipitation (IPCC 2007). Within Europe, Thuiller et
al. (2005) predict that by 2080 climate change will result
in a 27–42% loss of species, with potential extremes
ranging from 2.5–86% loss of current floristic diversity.
There have been few studies of the likely impact on
CWR diversity; however, Jarvis et al. (2008) undertook
a comparative study of three crop gene pools – Arachis,
Solanum and Vigna – and compared current distribution
Beta patula is a primary wild relative of cultivated beets and is an important gene source for enhancing drought and virus resistance. It is endemic to two small, uninhabited islets in
the Madeira archipelago – Ilhéu do Desembarcadouro and Ilhéu Chão – where it grows in dry, rocky places by the sea. It is threatened by invasive alien species, rabbit grazing and an
increase in the seagull population, and is globally assessed as Critically Endangered. B. patula is listed in Annex II of the EU Habitats Directive and the islands on which it occurs are
part of the Parque Natural da Madeira which is designated as a Special Area of Conservation (SAC) and Special Protected Area (SPA); however, special management measures are needed
to ensure the survival of this species. Photograph © Brian Ford-Lloyd.
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