Aliens Newsletter - ISSG

ut that control at a larger scale was required to better
define the timescale and costs involved. This
larger scale research was carried out in the form of
regional control trials between 1999 and 2002 by
CSL (the Central Science Laboratory (CSL), now
the Food and Environment Research Agency). Further
research by CSL was carried out nationally between
2003 and 2005 in order to refine the effectiveness
of winter shooting. This confirmed that
eradication was feasible and identified the shooting
of large winter flocks from boats as the most effective
way to reduce the population rapidly. Typically,
between 700 and 900 Ruddy Ducks were culled
each year during this period (1999–2005), leading
to an apparent slight decline in the national population
(Figure 6).
Significant opposition to Ruddy Duck control was
limited to certain animal rights groups, although
there was also opposition from many birdwatchers
and some nature reserve staff, particularly volunteers.
However this opposition was counterbalanced
by support from the country’s major conservation
bodies. The support of the UK’s leading conservation
charity, the Royal Society for the Protection of
Birds (RSPB) has been particularly crucial in helping
to convince site owners, managers and many
birdwatchers that the eradication programme is the
only effective way to eliminate the risk posed by the
Ruddy Duck to the survival of the White-headed
Duck.
The eradication programme
It has long been recognised that complete eradication
of Ruddy Ducks from Europe is the only effective
way to remove the threat to the White-headed
Duck (e.g. Green & Hughes 1996, Morley 2003)
and in 2005 the Food and Environment Research
Agency (FERA, an Executive Agency of the UK
Department for Environment, Food and Rural Affairs,
Defra) successfully applied to the European
Union LIFE-Nature programme for around 50% of
the cost of a £3.3M ($US4.95M) eradication programme.
The other 50% was provided by Defra and
a small contribution was received from the Spanish
Ministry of the Environment. The aim of this
programme has been the complete eradication of
Ruddy Ducks in the UK. However at the outset it
was recognised that this might not be achievable
within the five year timescale of the programme
(2005 to 2010) and FERA agreed to model the time
and costs likely to be associated with the removal
of any Ruddy Ducks which may remain at the end
of the LIFE-Nature project. Given the small size of
the original founder population, it is imperative that
complete eradication is achieved and the importance
of this is fully recognized by Defra and FERA, even
if it involves an extension of the current work.
At the outset of the programme we had a number
of advantages which helped the work to make good
progress:
• There is a great deal of information available on
Ruddy Duck numbers and distribution in the UK
from the monthly Wetland Birds Survey and elsewhere.
• Ruddy Ducks are highly visible compared to many
other species, especially during winter, and so are
relatively easy to locate and count.
• A very large proportion of the UK population is
to be found on a small number of “traditional” sites
in mid-winter.
• After ten years of research into control methods,
we had a good knowledge of the most effective
methods of controlling Ruddy Ducks and the
birds’ behaviour and habits.
However there were also some significant problems
which we have had to overcome, including the following:
• No powers of compulsory access – entry to sites
is only possible with the agreement of the site
owner or tenant.
• Hostility from some birdwatchers and local nature
reserve staff.
• The need to minimise the disturbance to native
species and disruption to other site activities such
as fishing or sailing.
Ten full-time staff are employed on the project (eight
shooting staff, one project manager and one footpath
warden) and all are FERA employees. All are
highly trained in both control methods and waterfowl
identification.
The control strategy and Ruddy Duck behaviour
The regional control trials showed clearly that control
of the wintering flocks, which make up a large
proportion of the total population, was the key to
bringing about a rapid reduction in numbers. In the
case of breeding season control, there is evidence
that if numbers are reduced on the best breeding
sites, birds are drawn into these from suboptimal
sites (CSL 2002). The strategy therefore has been
to concentrate winter control on large wintering
flocks, while breeding season control is concentrated
on the best breeding sites.
The behaviour of the Ruddy Duck has favoured effective
control, particularly in the winter, when
shooting from boats is the most usual method. The
large concentrations found on wintering sites fly
readily when approached by boats, although individual
birds are more likely to dive in order to escape.
On most sites a number of boats form a line
20 29/2010