30/03/2006 - The Environment
Agency is calling for designers and engineers working
on civil engineering schemes in Shropshire and elsewhere
to help prevent otters being killed on our roads.
By building ledges and mammal passes into bridges
and other river crossing structures, otters and
other small mammals can travel safely.
The future of Shropshire’s recovering
otter population may be in jeopardy because of the
increasing number being killed on local roads. Tomorrow
morning, seven otter carcasses are being taken to
a laboratory for post mortem to establish the exact
cause of death. As they were all discovered on local
roads recently, it seems most likely that they were
the victims of road accidents.
Otters are shy, nocturnal animals
that feed mainly on fish. The presence of otters
is an excellent indication of water quality. But
roads over and near watercourses form a major risk
to their nightly excursions for food and many otters
are being killed.
During the 1950’s the otter population
suffered a catastrophic decline, mainly due to two
chemicals used in agriculture, Dieldrin and Aldrin.
This decline continued throughout the 1960’s and
70’s, and by this time otters were effectively extinct
in the Midlands.
Otter populations are only now
recovering. Shropshire is one of the areas where
they are beginning to thrive, and an important area
in encouraging the spread of otters to other rivers,
such as the Trent.
Biodiversity Officer, Paul Hoban,
says: "It is such a shame to see so many of
these lovely creatures being killed or horribly
injured on our roads. At least 400 otters are killed
on Britain’s roads each year and we believe that
road accidents are now the biggest cause of otter
deaths.
"We are asking civil engineers
to help encourage otters to thrive by building in
ledges and mammal passes to structures such as bridges
and culverts so that otters and other small mammals
can travel safely through the countryside."
Otters in the Midlands
During the 1950’s the otter population
suffered a shattering decline, mainly due to two
chemicals used in agriculture, Dieldrin and Aldrin.
This decline continued throughout the 1960’s and
70’s, and by this time otters were effectively extinct
in the Midlands.
It was not until the otters were
given full legal protection in 1978 that they started
to make a steady comeback; improvements in water
quality, riverbank management and fish stocks also
aided in their return. Since the late 1970’s wild
otters have gradually repopulated most of the Severn
catchment.
Over the last 30 years, extensive
surveys for otters have been carried out. No otters
were found in the 1977-79 or 1984-86 surveys. It
was not until the 90’s that otters started to be
frequently witnessed.
Returning otters seem to cope
exceedingly well with the changes to river corridors
and footpaths, managing well in the drastically
increased urban sprawl.
Otters have been and still are
spotted in various towns and cities including Shrewsbury.
The otter is now fully protected in Britain under
the Wildlife & Countryside Act 1981. Despite
the increase of the otter in Britain they are still
classified by the IUCN as ‘vulnerable’.
A leaflet with more detailed information
is available on
http://www.environment-agency.gov.uk/commondata/acrobat/midlands_otters_816512.pdf
Otter facts and figures
Length: Average 1.2m (dogs),
1m (bitches)
Weight: Average 10.3kg (dogs), 7.4kg (bitches)
Colour: Medium to dark brown above and lighter underneath.
Diet: Mainly fish, but also birds, small mammals,
amphibians, crustaceans and molluscs.
Breeding: Only once every 2 years as the cubs remain
dependent on their mother for a year.
Gestation: 9 weeks
Offspring: 1-4 cubs
Lifespan: Average 4 years due to so many threats,
although they can live 8-12 years.
Habitat: Mainly rivers, but also canals, marshes,
small streams, ditches, ponds and lakes. They also
inhabit estuaries and coastal areas.
Home range: Depends on food supply but can be from
1 km along a rich coast to 40km along some rivers.
Resting sites: Called holts, often tree roots but
also drains, caves and holes in rockfalls. They
will also rest above ground in vegetation, sometimes
called couches.
Social structure: As otters are very territorial
they tend to live alone, except during mating and
for a period, dependent on the mother, after the
cubs are born.
Physical features: Short legs, webbed feet and claws,
long stream-lined body, small ears and a broad muzzle,
sensitive whiskers around snout to help detect prey,
2 layers of fur - a thick waterproof outer one and
a warm inner one.
Special abilities: The European otter has an acute
sense of sight, smell and hearing. The eyes are
placed high on the head so that it can see when
the rest of the body is below water.
