Indicator assessment
The indicator shows the change in status of
the 371 priority species assessed between 1999 and 2008. Every
three years, the status of each priority species has been assessed
by a range of experts across the UK. The indicator assessment is
based on the change in the status of 339 species for which a status
assessment is available in at least in one of the recording
years.
The Plan was revised in 2007 and the number of
priority species increased to 1,150, but assessments are not yet
available for this extended list.
For many species, status assessments are not
available for all recording years. To make best use of available
data, the change in status is assessed by comparing the earliest
available assessment for each species, with the most recent. The
majority of the earliest assessments (74%) are from 1999 or 2002.
The majority of the most recent assessments (85%) are from
2008.
Of the 339 species in the indicator, the
number that were assessed as either ‘stable’ or ‘increasing’ has
risen from 202 to 214. This modest improvement in the indicator is
assessed as positive, although there has been a slight fall in the
number of species actually ‘increasing’ from 48 to 45. In addition,
in 2008, 88 species were still declining and 6 were recorded as
lost from the UK since the Plan was published in 1994 (in addition
to species lost prior to the publication of the Plan).
Description of trends
Although the indicator shows a small net
increase in the number of species that are stable or increasing,
and the majority of species were reported in the same assessment
category in both 2005 and 2008, there has been some turnover of
species over the period 1999 – 2008.
In broad terms, the number of species that
have moved from the decreasing category to ‘stable’ or ‘increasing’
outweighs those moving in the other direction, but there are no
obvious patterns in these changes. Sixty six of the species that
were declining in 2008 were also declining in 2005. Six species
changed from declining in 2005 to lost in 2008. This turnover
between categories means that while the graph shows an increase in
the number of species stable or increasing, it is not necessarily
the same species which are improving. Species that have moved
from ‘decreasing’ in 2002 to either ‘increasing’ or ‘stable’ in
2008 include the shrill carder bee (Bombus syvarum), great
yellow bumblebee (Bombus distinguendus), reed bunting
(Emberiza schoeniclus) and the heath tiger beetle
(Cicindela sylvatica). Very few species have moved from
‘increasing’ to ‘declining’ although there are some examples:
Newman’s lady fern (Athyrium flexile) and fen orchid
(Liparis loeselii).
The ongoing increase in number of species
reported as lost, which came from the declining and unknown
categories in 2005 is an additional cause for concern. Table
3 (i) shows the number of species reported in each category in 2005
and in 2008.
Table 3 (i). Trend comparison between 2005 and 2008 for UK BAP
species
|
|
2005
|
2008
|
|
Declining
|
102 (28%)
|
88 (24%)
|
|
Increasing
|
41 (11%)
|
39 (11%)
|
|
Stable
|
131 (36%)
|
143
(39%)
|
|
Unknown
|
47 (13%)
|
61 (17%)
|
|
Lost
|
10 (2.7%)
|
15 (4.1%)
|
Twelve of the 47 species recorded as ‘unknown’
in 2005 (25%) were reported in as stable and one as
increasing in 2008.
There are 175 species for which there is a
status assessment available in three consecutive recording
years (2002, 2005 and 2008 – 1999 being a year with poor returns).
Figure 3 (iii) shows the change in status for these 175 species.
Although not making best use of all the available data, the figure
does show a similar trend, with a gradual increase in the number of
species recorded as either ‘stable’ or ‘increasing’ from 82 to
101.
Figure 3 (iii) Changes in the status of the UK priority
species, for 175 species that have been assessed in all recording
years 2002-2008
Relevance
The UK Biodiversity Action Plan (UK BAP) was
published in 1994 and is the UK’s national biodiversity strategy,
prepared in response to the UN Convention on Biological Diversity
(CBD). The UK BAP priority species are species of high nature
conservation value that are restricted in range or have suffered
significant population declines in the past. The plan sets out
targets for each species, reflecting the desire to maintain or
increase their range and population size. The targets are shared
goals of the UK Government, its Statutory Agencies and the
voluntary sector, but the indicator is assessed on the regular
status assessments for the species rather than on the progress
against detailed targets.
Background
The UK Biodiversity Action Plan originally
contained 391 plans (for 381 species and 10 species groups).
Species-groups are excluded from this indicator because there is
little information on their status over the period. In addition, a
number of the original priority species are now considered as
recognisable ‘varieties’ of other species rather than as separate
species in their own right. The remaining 371 species are included
in the indicator.
Status assessments for UK Biodiversity Action
Plans priority species were undertaken in 1999, 2002, 2005 and
2008. Assessments were undertaken by various conservation
organisations and agencies. The amount of data available
varies from species to species; so some assessments were based on
comprehensive survey and some on expert opinion. The indicator
takes the assessments at face value.
The first assessment (in 1999) took place very
soon after many of the plans were published and comparatively few
assessments were made. The indicator therefore compares the
earliest available status assessment (i.e. 1999 if it is available,
2002 if it is not, 2005 if neither 1999 or 2002 are available)
against the latest (2008, if available, 2005 if not and so on).
As can be seen from Figure 3 (ii), the
categories used in 2008 (and in each of the previous three
assessments) were more detailed than the four categories used in
the indicator. This is because different assessment categories were
used in the four years and they have been compiled to allow easier
comparison across years (Table 3 (ii)).
The 2009 presentation is a refinement of the
indicator published in 2007 which presents data for 189 species
from 2002 and 2005 only. A technical background paper is available
and provides a more detailed description of the method (see
attachments below).
Table 3 (ii). Consolidation of status assessment categories for
presentation in the indicator.
|
Categories used in the
indicator
|
Categories used in the original
assessments
|
|
Increasing
|
Fluctuating - probably increasing
Recovered
Signs of recovery
Increasing
|
|
Stable
|
Fluctuating - probably stable
No change
Stable
|
|
Decreasing
|
Declining (continuing/accelerating)
Declining (slowing)
Fluctuating - probably declining
Lost (pre BAP publication)
Lost (since BAP publication)
No data entered Lost pre UK BAP
Unknown (presumed extinct)
|
|
Unknown
|
Insufficient information
Fluctuating / No clear trend
No clear trend
No data entered
Unknown
|
Further development planned
The UK BAP priority species and habitats have been reviewed
and the new UK List of
priority species and habitats was published in August 2007.
Future reporting needs for the new list of species and habitats are
still to be determined.