| Tayside Biodiversity - Tayside
Biodiversity Action Plan - Farmland - Wet Grassland |
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INTRODUCTION
Wet grassland is one of the most rapidly diminishing wetland types in Britain.
Our coastal grazing marshes, floodplains, wash lands, water meadows and river
valley pastures are part of a traditional farming system. Losses of wet grassland
have only been well documented since the Second World War, but in this period
there have been dramatic declines in breeding wading bird populations and the
other flora and fauna assemblages associated with this habitat.
The value of the wet grassland habitat is becoming increasingly recognised beyond
the benefits it provides over and above its conservation value. Flood alleviation,
nutrient and pollution absorption and groundwater recharge are all
additional benefits being utilised. The management of existing wet grassland
and the possibility of its restoration or creation should all aim to take advantage
of these functional values. A wider vision of the value of wetlands within floodplains
and catchments should also be developed. |
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DEFINITION
Wet Grassland is, for the purpose
of this Habitat Action Plan, defined as periodically inundated
pasture or meadow with ditches which maintain the water levels
containing standing brackish or fresh water. Almost all areas are
grazed and some areas are cut for hay. Sites may contain seasonal
water-filled hollows and permanent ponds with tall fen species
such as reeds, but not extensive areas.
This is comparable with the definitions used by the Biodiversity Steering Group
for Coastal and Floodplain Grazing Marsh and by The Wet Grassland Guide. This
definition includes the following broad wetland types:
Semi-natural floodplain grassland
This occurs where floodplains are subjected to a semi-natural hydrological regime.
Insh Marshes in Strathspey is an excellent example of this. Naturally functioning
floodplains are rare in the UK where most rivers are intensely regulated and
engineered.
Water meadows
In some areas deliberate controlled flooding was used to boost fertility, raise
hay yields and enable grazing earlier in the year.
Wet grassland with intensive water level
management on drained soils
Many wetlands on both peat and alluvial soils have been converted to productive
agricultural grassland (for example some areas of Montrose Basin). These areas
now have artificial highly regulated water regimes. The grass mixture is frequently
improved. However, some areas still
contain significant botanical interest within field areas and drainage ditches.
Lochside wet grassland
These are areas of wet grassland around the margins of lochs which may be temporarily
inundated owing to seasonal water level increases, for example Loch Kinnordy. |
Other
areas to consider for conversion or re-instatement could well
include land currently under intensive grassland or even cereal
production.
Sites/ Site Distribution
Parts of: Strathallan
Strathmore
Loch Freuchie Meadows (SSSI)
Glen Clova
Tay/Isla Valley
Montrose Basin |
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CURRENT STATUS
AND EXTENT OF HABITAT
There is an estimated 300,000 hectares
of grazing marsh in the UK which includes wet grassland and coastal
marshes. Scotland’s allocation of this total is believed
to be in the region of 40,000 ha. Only a small proportion of this
overall figure is semi-natural, supporting a high diversity of
native plant species (2,500 ha in Scotland, Ireland and Wales).
Although no full estimate for the extent of wet grassland is currently
available for Scotland, Newson estimated around 3,000 km2 as having
potential. Wet grassland (or land with the potential to be so)
in Tayside is largely distributed along
the main straths and glens, but exists in varying size of area throughout the
region. While there are some excellent examples, overall the region’s wet
grassland is greatly reduced as most potential areas are intensively farmed.
NATURE CONSERVATION IMPORTANCE
Wet grassland is important for breeding waders and wintering waterfowl. Farmland
birds, including Skylark Alauda avensis, are also important species of this habitat.
Wet grassland can provide significant hunting territory for Barn owl Tyto alba
and Short-eared owl Asio flammeus, as well as Merlin Falco columbaris and Peregrine
falcon Falco peregrinus. This habitat is typically diverse in plant species and
supports many different invertebrate species. |
KEY
SPECIES
P = UK Priority species C = UK species of conservation concern
| Mammals |
Otter |
Lutra lutra |
P |
| Water vole |
Arvicola terrestris |
P |
| Pipistrelle bat |
Pipistrelle pipistrellus |
P |
| Birds |
Redshank |
Tringa totanus |
C |
| Lapwing |
Vanellus vanellus |
C |
| Snipe |
Gallinago gallinago |
C |
| Curlew |
Numenius arquata |
C |
| Wigeon |
Anas penelope |
C |
| Teal |
Anas crecca |
C |
| Skylark |
Alauda arvensis |
C |
| Barn owl |
Tyto alba |
C |
| Short-eared owl |
Asio flammeus |
C |
| Merlin |
Falco columbaris |
C |
| Peregrine falcon |
Falco peregrinus |
C |
| Amphibians
and Reptiles |
Common Frog |
Rana temporaria |
C |
| Common Toad |
Bufo bufo |
C |
| Invertebrates |
Small pearl-bordered fritillary |
Boloria selene |
C |
| Sword Grass moth |
Xylena exsoleta |
P |
| Damselfly spp. |
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| Grasshopper spp. |
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| Hoverfly spp. |
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| Plants |
Brackish water-crowfoot |
Ranunculus baudotii |
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| Pillwort |
Pilularia globulifera |
P |
| Ragged Robin |
Lychnis flos-cuculi |
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| Selfheal |
Prunella vulgaris |
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| Yellow rattle |
Rhianthus minor |
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| Greater Birdsfoot trefoil |
Lotus uliginosis |
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| Globe flower |
Trollius europeaeus |
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| Jointed Rush |
Juncus articulatus |
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| Northern Marsh Orchid |
Dactylorhiza purpurella |
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| Fungus spp. |
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Lapwing
Over the past 25 years there has been a dramatic UK decline
in the lapwing population, but its numbers in Tayside seem
to remain optimistically constant.
The species will nest on open farmland as well as wet grassland.
They prefer to nest in large fields with good all-round visibility.
Pairs will often nest nearby to increase their protection
from predators. Although they feed on a wide range of invertebrates,
earthworms are a particularly important part of their diet. |
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NATIONAL BIODIVERSITY
CONTEXT
There is a UK Habitat Action Plan
for Lowland Wet Grassland. Its main objectives are:
Maintain existing diversity, distribution and extent. Evaluate other habitat
types fully.
Maintain and, where technically and ecologically practicable, enhance the extent
and distribution of wet grazing levels.
Re-establish nationally important assemblages of plants, invertebrates, breeding
wading birds and nationally important concentrations of wintering waterfowl.
Restore wet grassland from drier, semi-improved or improved grassland or arable
land over the next five years. |
Globe
flower
These distinctive plants with their large buttercup-like
flowers grow in wet upland pastures.
The effects of global warming are being widely researched
and it is species such as the Globe flower, which prefers
a cool northerly climate, that are under increasing scrutiny. |
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