DaveN
Derwent Valley Birder
Whatever your views on the cull of Ruddy Ducks I received an interesting letter the other day on the progress of their eradication.
UK RUDDY DUCK ERADICATION PROGRAMME
PROJECT BULLETIN, APRIL 2008 TO MARCH 2009
Summary
● Between April and August 2008, 219 ruddy ducks were culled.
● During the period September 2008 to March 2009 a total of 1,065 ruddy ducks were culled.
● Control was carried out on 60 sites from Easter Ross in the north of Scotland to Devon, Surrey
and Kent in the south of England.
● An independent count of 103 sites across Great Britain by Wildfowl and Wetlands Trust in
January 2009 found a total of 687 ruddy ducks. Since that date 424 have been culled.
Background
The ruddy duck Oxyura jamaicensis is a North American bird introduced to the UK over 50 years ago.
A small number escaped from captivity and formed a feral population which numbered around 6,000
by January 2000. Since the early 1990s ruddy ducks, almost certainly originating from the UK, have
appeared in Spain where they hybridise with the native white-headed duck Oxyura leucocephala. In
the long-term hybridisation could lead to the extinction of the white-headed duck.
Following several years of research into the most effective control methods, the eradication
programme began in September 2005. It is due to run until August 2010 and is financed by the EU
LIFE-Nature Programme and the Department for Environment, Food and Rural Affairs (Defra). The
Spanish Ministry of the Environment is a partner in the project. It was estimated that at the beginning
of the Eradication Programme the UK population was around 4,400 birds, and since that time 6,159
birds have been culled. The difference in the figures is largely accounted for by recruitment of some
juveniles into the population in each breeding season
Progress in the UK since April 2008
A total of 1,284 ruddy ducks were shot on 60 sites between 1 April 2008 and 31 March 2009. Adult
males made up 36% of the total number shot, adult females 27% and immature birds 37%. The
proportion of immature birds was slightly higher than in previous years and probably reflects slightly
better breeding success now that reduced numbers have allowed a larger proportion of the UK
population on to the best breeding sites. However, as the population has fallen the birds are to be
found on fewer sites. The Food and Environment Research Agency (formerly Central Science
Laboratory) is now targeting breeding and wintering sites which have not previously been visited.
Control took place on 20 sites for the first time in the year to 31 March 2009.
Independent monitoring of ruddy duck numbers
Since the start of the eradication programme, the Wildfowl & Wetlands Trust (WWT) has carried out
independent surveys of key ruddy duck wintering sites in the UK. As the eradication has progressed
and numbers on the principal wintering sites have fallen, more sites have been surveyed to ensure
better coverage and accuracy. Two co-ordinated counts were carried out by WWT in Great Britain in
December 2008 and January 2009. During the December count 104 sites were visited and 787 ruddy
ducks were recorded. During the January count 103 sites were visited and 687 birds were recorded.
Since the January 2009 count of 687 birds, Fera has culled 424 ruddy ducks. Although there has been
a large decline in the number of ruddy ducks over the four most recent winters, the population has
remained concentrated on relatively few sites. In January 2009 the top 20 sites held 90% of the total
number counted. This suggests that ruddy ducks are not becoming more widely dispersed as a result of
the eradication programme. Three separate counts in Northern Ireland, carried out in October 2007,
January 2008 and March 2008 found a peak count of only 27 ruddy ducks. All but six of these were
confirmed as male birds, suggesting that productivity in Northern Ireland will be very low in 2009.
Progress in Europe
A second European workshop was held in Nantes in north-western France in November 2008. This
was attended by representatives from France, the Netherlands, Spain and the UK. Information on
ruddy duck numbers in Belgium and Germany was also made available to the workshop. It appears
that the UK, France and the Netherlands are the only countries with self-sustaining populations. Ruddy
ducks remain rare in Belgium, Germany and Ireland, and numbers in these countries are probably less
than three breeding pairs in each.
Ruddy duck numbers in France have been slowly increasing, and in winter 2007/08 the population was
estimated to be around 350 birds. It is thought that there are between 40 and 60 breeding pairs. The
French authorities have been carrying out control for several years but now recognise that the
effectiveness of their control programme must be increased if eradication is to be achieved. To date
there has been no control of ruddy ducks in the Netherlands, although peak numbers there have
declined in two of the last three winters, from 97 in winter 2005/06 to 60 in winter 2008/09. This could
suggest possible movement of birds between the Netherlands and the UK. However, the breeding
population in the Netherlands has increased in recent years, and was estimated at 22 pairs in 2008. The
Dutch Government has recognised the need to eradicate ruddy ducks in the Netherlands and is
currently making the necessary administrative changes which will allow control.
In Spain the control programme is ongoing and six ruddy ducks were seen in Spain in 2008, all of
which were culled. No hybrids were reported in Spain in 2008.
Further general information on the project can be found www.nonnativespecies.org
UK RUDDY DUCK ERADICATION PROGRAMME
PROJECT BULLETIN, APRIL 2008 TO MARCH 2009
Summary
● Between April and August 2008, 219 ruddy ducks were culled.
● During the period September 2008 to March 2009 a total of 1,065 ruddy ducks were culled.
● Control was carried out on 60 sites from Easter Ross in the north of Scotland to Devon, Surrey
and Kent in the south of England.
● An independent count of 103 sites across Great Britain by Wildfowl and Wetlands Trust in
January 2009 found a total of 687 ruddy ducks. Since that date 424 have been culled.
Background
The ruddy duck Oxyura jamaicensis is a North American bird introduced to the UK over 50 years ago.
A small number escaped from captivity and formed a feral population which numbered around 6,000
by January 2000. Since the early 1990s ruddy ducks, almost certainly originating from the UK, have
appeared in Spain where they hybridise with the native white-headed duck Oxyura leucocephala. In
the long-term hybridisation could lead to the extinction of the white-headed duck.
Following several years of research into the most effective control methods, the eradication
programme began in September 2005. It is due to run until August 2010 and is financed by the EU
LIFE-Nature Programme and the Department for Environment, Food and Rural Affairs (Defra). The
Spanish Ministry of the Environment is a partner in the project. It was estimated that at the beginning
of the Eradication Programme the UK population was around 4,400 birds, and since that time 6,159
birds have been culled. The difference in the figures is largely accounted for by recruitment of some
juveniles into the population in each breeding season
Progress in the UK since April 2008
A total of 1,284 ruddy ducks were shot on 60 sites between 1 April 2008 and 31 March 2009. Adult
males made up 36% of the total number shot, adult females 27% and immature birds 37%. The
proportion of immature birds was slightly higher than in previous years and probably reflects slightly
better breeding success now that reduced numbers have allowed a larger proportion of the UK
population on to the best breeding sites. However, as the population has fallen the birds are to be
found on fewer sites. The Food and Environment Research Agency (formerly Central Science
Laboratory) is now targeting breeding and wintering sites which have not previously been visited.
Control took place on 20 sites for the first time in the year to 31 March 2009.
Independent monitoring of ruddy duck numbers
Since the start of the eradication programme, the Wildfowl & Wetlands Trust (WWT) has carried out
independent surveys of key ruddy duck wintering sites in the UK. As the eradication has progressed
and numbers on the principal wintering sites have fallen, more sites have been surveyed to ensure
better coverage and accuracy. Two co-ordinated counts were carried out by WWT in Great Britain in
December 2008 and January 2009. During the December count 104 sites were visited and 787 ruddy
ducks were recorded. During the January count 103 sites were visited and 687 birds were recorded.
Since the January 2009 count of 687 birds, Fera has culled 424 ruddy ducks. Although there has been
a large decline in the number of ruddy ducks over the four most recent winters, the population has
remained concentrated on relatively few sites. In January 2009 the top 20 sites held 90% of the total
number counted. This suggests that ruddy ducks are not becoming more widely dispersed as a result of
the eradication programme. Three separate counts in Northern Ireland, carried out in October 2007,
January 2008 and March 2008 found a peak count of only 27 ruddy ducks. All but six of these were
confirmed as male birds, suggesting that productivity in Northern Ireland will be very low in 2009.
Progress in Europe
A second European workshop was held in Nantes in north-western France in November 2008. This
was attended by representatives from France, the Netherlands, Spain and the UK. Information on
ruddy duck numbers in Belgium and Germany was also made available to the workshop. It appears
that the UK, France and the Netherlands are the only countries with self-sustaining populations. Ruddy
ducks remain rare in Belgium, Germany and Ireland, and numbers in these countries are probably less
than three breeding pairs in each.
Ruddy duck numbers in France have been slowly increasing, and in winter 2007/08 the population was
estimated to be around 350 birds. It is thought that there are between 40 and 60 breeding pairs. The
French authorities have been carrying out control for several years but now recognise that the
effectiveness of their control programme must be increased if eradication is to be achieved. To date
there has been no control of ruddy ducks in the Netherlands, although peak numbers there have
declined in two of the last three winters, from 97 in winter 2005/06 to 60 in winter 2008/09. This could
suggest possible movement of birds between the Netherlands and the UK. However, the breeding
population in the Netherlands has increased in recent years, and was estimated at 22 pairs in 2008. The
Dutch Government has recognised the need to eradicate ruddy ducks in the Netherlands and is
currently making the necessary administrative changes which will allow control.
In Spain the control programme is ongoing and six ruddy ducks were seen in Spain in 2008, all of
which were culled. No hybrids were reported in Spain in 2008.
Further general information on the project can be found www.nonnativespecies.org
