CLM Spring issue 2018 - Page 37

The increasing importance of monitoring wildlife responses to habitat management
Chalk grassland, Kent
The Medway Smile Living Landscape contains several fine
examples of unimproved calcareous grassland, such as those
along the Wouldham to Detling Escarpment and Queendown
Warren SSSIs. These sites are botanically rich and support many
plant and invertebrate species of elevated conservation priority,
such as Early Spider-orchid Ophrys sphegodes and Adonis Blue
butterfly Polyommatus bellargus. The project run by the Kent
Wildlife Trust aims both to restore and to create areas of speciesrich grassland on calcareous soils, and to maintain the existing
quality of established sites. Management is through grazing with
Recent scrub removal on chalk grassland
cattle and sheep, restoration through scrub control, and creation
near Detling, Kent. Rob Fuller
on former agricultural land through reseeding and conservation
grazing of former pasture. Monitoring aims to answer the questions of (i) whether restoration by scrub removal
and creation by agricultural reversion produce species-rich grassland that can support key plant and invertebrate
species, (ii) how rapidly changes in plant and invertebrate communities occur, and (iii) how restored and created
habitats compare with established grassland. Plant communities, butterflies and ground beetles will be monitored
by means of, respectively, 2×2m quadrats, line transects, and pitfall traps and direct searching, in replicates of
core, restoration and new habitat, and of current and historical management. Established sites will be used as
benchmarks against which changes are assessed.
Grazing and turf-stripping on lowland heathland, West Sussex
The Sussex Wildlife Trust’s Iping and Stedham Commons reserve (125ha) consists of large areas of heathland,
Purple Moor-grass Molinia caerulea mire, birch–pine Betula–Pinus woodland and small areas of wet heath.
Stedham has been ‘pulse’-grazed for more than 10 years with cattle. Iping is currently not fenced and, because
of the lack of grazing, is losing key species such as the reintroduced Field Cricket Gryllus campestris. Heath Tiger
Beetles Cicindela sylvatica have been reintroduced on Iping on purpose-made ‘scrapes’ (the stripped turfs used
to create more heathland on nearby golf courses). Invertebrate-monitoring has examined the effects of grazing
in three areas similar in vegetation and aspect. These were: (i) grazed for 10 years; (ii) summer-grazed, with
temporary electric fencing used; and (iii) a control plot with no livestock grazing. All invertebrates were recorded
within a one-hour period by several observers, using a range of methods. Records were bulked over multiple
visits from April to September. Comparisons between plots were made in terms of the guild composition of the
invertebrate assemblages. On the scrapes, Heath Tiger Beetles and other invertebrates were counted by observers
walking each scrape at a steady pace per unit area. These data were used to show which scrapes produced the
most beetles and the greatest diversity of bare-ground invertebrates.
accordance with the speed with which vegetation
and other habitat conditions change in relation to the
habitat needs of the target organisms. The rapidity
of successional change tends to be far greater in
the early stages of habitat development than in
later stages. The niches for many early successional
species are available for only short periods, so that, if
sampling intervals are too wide, these may be missed.
It may be possible to adopt mixed sampling intervals,
whereby either (i) certain taxa are monitored at
shorter intervals than others or (ii) a small sample
of sites is monitored at short intervals but a much
larger sample is then monitored at longer intervals.
Rotational management, gradients and
shifting mosaics
Conservation management frequently involves
rotational cutting or mowing, this being the case in
many habitat-restoration projects. The conservation
interest may reside in the overall diversity created by
the resulting vegetation gradients, or may be more
focused on particular developmental stages (usually
the earlier stages) or the transitions between patch
types. Monitoring may be relevant when comparing
different rotational treatments or simply in assessing
whether ongoing management is providing suitable
habitat for target species. It may be necessary to
stratify the samples that are taken so that particular
stages of vegetation development or transitions are
sampled over periods of time.
Monitoring wildlife responses to rotational
management or shifting mosaics does not necessarily
involve the use of strict controls or reference plots,
because the comparisons are essentially those made
between the different stages of development. There
may, however, be instances when controls would be
desirable, especially when a comparison is needed
February 2016 British Wildlife 183
BWM27_3 07 monitoring-v2.indd 183
29/01/2016 13:49


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