Carried out by the Office
for National Statistics (ONS) and Miller Mitchell Burley Lane
on behalf of the Office of the Deputy Prime Minsiter; Commensal
rodent element funded by Defra and analysed by CSL
The English House Condition Survey is the only dwelling-based
survey undertaken in England. Data on the infestation of dwellings
by commensal rodents were collected for the first time during the
1996 EHCS and analysed by CSL. The rodents concerned were the house
mouse (
Mus domesticus) and the common rat (
Rattus
norvegicus). House mouse infestations inside properties and
common rat infestations both inside and outside were considered. A
repeat survey was carried out in 2001.
Methods: the practical aspects of the
commensal rodent element of the overall survey were undertaken
during a 10 week period between April and July 1996. A physical
survey of dwellings was carried out by approximately 100
professional surveyors, trained in detecting signs of rodent
infestation.
Site coverage: England only. Approximately
12,000 properties surveyed.
Species coverage: house mouse and common
rat.
The analyses of the 2001 EHCS commensal rodent data are
completed and offer the first objective view of recent trends for
commensal rodent populations. The EHCS was re-organised as a
continuous survey from financial year 2002/3. In future years,
annual results will be available based on rolling combinations of
two year data sets (i.e. next results were available at
the end of 2005 based on the period 2004 and 2005). This approach
will provide a robust base for analysis and monitoring of
change.
Latest information:
BTO Garden
BirdWatch
Run by BTO; Funded by participants'
contributions
The BTO's Garden BirdWatch
scheme was expanded in 2003 to trial the collection of
information on presence-absence of a range of mammals, butterflies,
amphibians and reptiles. Since 2005, the recording of other
wildlife within gardens has become a core component of the
project.
Methods: volunteers are asked
to record the presence of birds, mammals and other species in their
garden on a weekly basis throughout the year. Although the amount
of time spent recording may vary between volunteers, the volunteers
themselves are consistent in their efforts from one week to the
next.
Site coverage: UK. In the
pilot survey of 2003 over 8,000 survey forms were returned. In 2004
over 4,000 were returned by post and over 2,000 were recorded
online. Records are received from roughly 10,000 gardens in any
given week, with most observers choosing to record other wildlife
species they encounter.
Species coverage: The pilot
work suggested that 19 mammal species were sufficiently common in
gardens to allow the collection of information for monitoring
purposes. These include hedgehog, mole, common shrew, pygmy shrew,
rabbit, brown hare, red squirrel, grey squirrel, bank vole, field
vole, wood mouse, yellow-necked mouse, house mouse, common rat,
fox, badger, roe deer, muntjac and feral cat. There was some
variation in the confidence of observers to identify different
species. Observers felt most confident to identify hedgehog, mole,
rabbit, brown hare, red squirrel, grey squirrel, common rat, fox,
badger and cat. They were least confident in identifying common and
pygmy shrew, bank and field vole and yellow-necked mouse.
Therefore, while this survey has the potential to provide
information on small mammals, the ability of observers to correctly
identify individual small mammal species may affect the
results.
Survey power: GBW has
adequate power to detect a decline in presence of 5-40% at a
national level for 9 of the 23 target mammal species (hedgehog,
mole, rabbit, grey squirrel, wood mouse, house mouse, common rat,
fox and cat). There were just four mammal species (otter, pine
marten, water shrew and fat dormouse) for which there was not
adequate power to detect a 'useful' decline in presence at the
national level (defined here to be a decline of 50% or more).
Examining power at a regional/country level, suggests that it
should be possible to detect a 'useful' level of decline in
presence for a large proportion of the species that can be
monitored at the national level. The results from the 'matched'
analysis are very similar to the 'unmatched' design at the national
level.
Latest information: detailed information on
species counts can be obtained on the
BTO website
Living with Mammals
Run by PTES/ MTUK with scientific input from RHUL;
Funded by MTUK
Living with Mammals
is a pilot scheme, launched in 2003, aimed at producing
indices of mammal abundance near built land (not only in gardens),
mainly in towns but also in the countryside.
Methods: volunteer surveyors were asked to
record the maximum number of each mammal species seen together at a
site each week between April and June. Volunteers were provided
with a small booklet of information on UK mammals to aid
identification.
Site coverage: Great Britain. In 2003, data
from 808 survey forms were analysed. Of these, 792 (98%) recorded
the presence of at least one wild mammal species.
Species coverage: 24 species or groups of
species (e.g. bats) were recorded, including a number of
protected species and some of high conservation concern such as
water vole. Results suggest that population trend information could
be obtained for at least eight species including: hedgehog, mole,
rabbit, grey squirrel, common rat, feral cat, fox and badger.
Survey power: the power of the survey to
deliver population trend information has not been fully assessed
and will require several more years of data.
Latest information: