Introduction to the guidance manual
17. Assessing trends in condition
The critical distinction to be made when judging the condition
of interest features on statutory sites is between favourable and
unfavourable condition. However, the framework of condition
categories agreed as part of common standards monitoring includes
sub-categories relating to trends in feature condition. If a
feature is assessed as being in unfavourable condition, it is
important to be able to judge whether it is recovering, stable, or
declining. This is critical to informing decisions about the
management of sites.
17.1 Habitats and earth heritage features
For the 'unfavourable - recovering', 'unfavourable - no
change' and 'unfavourable - declining' categories, the basis for
assessment is the availability of evidence which demonstrates a
trend. This evidence will often be that obtained by comparing the
attribute targets with baseline information or by information
obtained on a previous monitoring occasion. However, evidence can
also be obtained by inference. For example, information on recent
and current grazing levels and their impact on the condition of
heathland vegetation may be provided by the structure of heather
and other dwarf shrubs, including the presence of distinctive
growth forms and the proportion of grazed shoots. In woodlands, the
growth of seedlings/saplings will provide an indication of grazing
levels and the potential for woodland regeneration. Evidence of
recent removal of non-native trees indicates the composition
attribute target may be improving. Wherever possible, attributes of
this type have been included in the habitat guidance, but suitable
attributes are not available for all management factors.
Finally, knowledge of the management regime and other factors
affecting the site (e.g. air pollution) can also contribute to
judgements about whether a feature is likely to be recovering or
declining. For example, if an area of degraded blanket bog (in
unfavourable condition) is being grazed heavily and regularly
burnt, it is fairly safe to assume that its condition will not be
improving. However, this approach relies on being confident that
particular management treatments will lead to certain changes in
condition, rather than directly assessing any changes.
Assessing condition in the 'recovering', 'no change' and
'declining' sub-categories at the time of the first assessment, can
be achieved using the evidence referred to above.
In subsequent six year cycles, trends in condition could be
assessed in various ways:
- changes in the number of attributes 'failing';
- trends in the number of samples 'failing';
- trends in the values of attributes;
- changes in the area of the habitat/extent of landform/rock
exposure in favourable/unfavourable condition.
Different habitats have different response times - it may be
possible to restore some grassland vegetation within a few years,
but blanket bog may take decades - and the ecology of a feature
needs to be taken into account when judging condition. The rate of
progress from unfavourable to favourable condition will also be
determined by management. For example, on upland heathland the
complete removal of livestock will probably lead to favourable
condition being attained much more rapidly than if more modest
stock reductions are put in place. The end-point will be the same,
but the rate of progress will be markedly different.
Ultimately, it is for the person carrying out the assessment
to examine the evidence and formulate a view based upon it. They
then need to record their reasons for their view. If the evidence
appears dubious or weak as regards any trend, an assessment of
no change is to be preferred.
17.2 Species
Species present particular problems, including the often
poorly understood relationships between species populations and
their habitat, and the difficulty in interpreting quantitative
population measurements given the widely fluctuating population
dynamics of many species. For many species, it may be impossible to
use population attributes to determine the sub-categories in any
meaningful way, and other evidence will have to be considered when
assessing trends for these. For example, it may be possible to
infer recovery from improvements in one or more of the habitat
attributes. Where possible, the guidance for species features will
give advice on how to evaluate trends.
17.3 Unfavourable Recovering
The generality of the foregoing remarks apply to undertaking
the assessment of feature condition in relation to the
Unfavourable Recovering category. At first assessment a
view will be formed after considering the available direct and
indirect evidence to determine whether the feature is, in fact,
recovering. Where management has been put in place to address all
the factors preventing the feature from returning to favourable
condition, and in the best judgement of the assessor such a return
will occur in due course, the feature should be assessed as falling
in the unfavourable recovering category, notwithstanding
that full recovery may take several years. However, a distinction
is made here between management leading to full recovery and that
which is limited to some improvements. For recovery, remedial
measures should have been taken to address all failing attributes;
recovery will not occur if only some of the attributes have been
addressed. While the latter will lead to improvement, it will not
lead to favourable condition being attained, and features in this
condition should be assessed as falling in the unfavourable no
change category.
17.4 Favourable recovered
As soon as the favourable condition threshold is exceeded, the
state changes from unfavourable recovering to favourable
recovered. Common Standards Monitoring should not be expected
to determine if the management is correct, merely point out if the
condition of a feature on a site is as we wish it to be. Although
it is undesirable for a feature to fluctuate between favourable and
unfavourable conditions, what this may mean is that the management
of the site/feature is failing the feature in some way.
17.5 Partially Destroyed
It is not unusual for the condition of a feature within a
protected area to vary between different parts of the site. This
might have been the case at designation or have happened
subsequently. If the condition of part of a feature is considered
to be, for whatever reason, beyond restoration, it will cease to be
a target for future management actions and is consequently not
usefully monitored from that point onwards.
The partially destroyed condition should then be
applied to that part of the feature and that part will be excluded
from future condition assessment. Such an assessment would need to
be accompanied by corresponding changes to any variables in
attributes or targets (e.g. extent) within the conservation
objectives for the remainder of the feature. The partially
destroyed category can apply to all types of features. For
habitats, it may apply because of permanent habitat loss within the
site. A species example might be permanent loss of part of a
population because of factors acting outside of the site such as
climate change. Within the Earth sciences, the category might apply
to loss of part of a mineral or fossil feature.
Use of the partially destroyed category is important
in order that destroyed parts of a feature on a site do not mask
and detract from the condition of remaining viable feature
components. Without this category one could envisage a situation
where the destruction of part of a feature resulted in permanently
unfavourable condition of that feature and, therefore, removed
incentives to manage the remainder.
There are some practical issues that need to be resolved in
handling and reporting use of this category:
- It is important that the extent of a partially
destroyed feature is reported even though it would not be
subject to monitoring. This means that partially destroyed
features will be reported as two separate elements (including when
the first assessment at which the feature is discovered to be
damaged), one a constant partially destroyed element, and the
second the condition of the remainder of the feature (which might
be any of the favourable or unfavourable states).
- It is important that partially destroyed is not
applied to unfavourable components of a feature simply to avoid
long and intensive management programmes. Where possible, guidance
for features will use attributes and targets capable of determining
the issue of whether a feature is partially destroyed.
17.6 Destroyed
The same principles apply to the use of the destroyed
condition category, except that it relates to an entire feature. If
a feature is considered to be, for whatever reason, beyond
restoration, then it should be reported as having been
destroyed. In this instance, the practical implication is
that no management will take place to restore the feature and, if
this is the sole feature on a site, the site will cease to be
monitored.
There are obvious scenarios in which a feature, or part of it,
has been destroyed beyond restoration, such as due to complete loss
of habitat from erosion, excavation or permanent covering (e.g.
roads). In such cases, not only will the feature itself change, but
the processes that are essential to support it will have been
irretrievably lost. This applies equally to habitat and species
features.
When a feature, or part of it, has been destroyed, but the
underlying processes that supported it remain viable, then it may
be possible to restore it. In this circumstance, the feature cannot
be considered truly destroyed as it is likely to re-establish and
so it should be regarded as unfavourable. Examples might include:
the loss of a plant species due to herbicide application, loss of
trees from wind-throw, loss of a bird species due to disturbance
events, loss of an amphibian due to a pollution event, etc.
However, there are limits to the kind of management that could be
undertaken to restore a feature and if a feature is unlikely to
re-establish then generally it should be considered destroyed.
Careful consideration will need to be given to which state to use
when the impact on the feature comes from beyond the site boundary.
The work necessary to enable restoration or re-establishment to
take place may be difficult or long term; this should not be an
excuse to use the destroyed categories; these should only be used
when the feature cannot be restored.
It is recommended that all cases where a feature is considered
to be either partially destroyed or destroyed
should be reviewed by the relevant advisory staff to ensure
consistency in these assessments.