Skip navigation

Common scoter BAP report

Flock of common scoters sleeping
The UK breeding population of this small diving seaduck has substantially declined

What are we trying to achieve?

The Government agreed a Biodiversity Action Plan for this species in 1998. The targets for this plan were revised in 2006 and are as follows:

  • Increase the breeding population to at least 100 pairs by 2010
  • In Scotland, maintain at least the existing breeding range (23 occupied 10 km squares
  • Regain common scoter as a breeding species in Northern Ireland by 2015
  • Maintain the current range of moulting common scoters
  • Maintain the current range of wintering common scoters
  • Maintain the current population of wintering common scoter

We are working with our Joint Lead Partner, the Wildfowl and Wetland Trust, (WWT) to conserve this nationally threatened waterfowl species whose small UK breeding population has declined in range by more than 50% in the last 25 years. Many birds that have bred in the tundra areas of Northern Europe spend the winter in UK waters, feeding mainly on shellfish.

What is the RSPB doing to help?

During 2006, the RSPB:

  • Continued to carry out two spring breeding population surveys in the Flow Country, northern Scotland
  • Continued regular brood surveys of common scoter on a maximum of 129 sites in the Flow Country, with reserve coverage for the seventh year
  • Carried out a literature review on conservation requirements for scoter; this will be used to inform next research steps
  • Collaborated with the Forest Enterprise (FE) and Forestry Commission (FC) as part of a EU-funded LIFE Nature project to remove conifers in the Flows including the catchments of some key common scoter breeding sites
  • Attempted to prevent common scoter eggs being stolen by egg collectors
  • Helped organise and fund the Wetland Bird Survey (WeBS) to monitor the wintering and moulting populations
  • Lobbied for tighter controls on the transport of oil around UK waters and the designation of marine protected areas and responded to development threats for this species in inshore waters

Summary of progress

During the last breeding survey, in 1995, there were 195 breeding females in Great Britain and Ireland. 95 pairs bred at 61 sites in Scotland and 100 pairs at just 4 sites in the Republic of Ireland. None were breeding in Northern Ireland (compared with 150 pairs in 1967). In the Flow Country, numbers had declined from 55 pairs in 1988 to 36 in 1995 (and 28 in 1996). In 2002, a count of almost all former breeding sites in the Flow Country found 26 pairs. A repeat survey of the same sites in 2003 found 29 pairs.

In 2004, declines of 25% in the Flow Country (1995-2004), 20% in a sample in the West Highlands (1995-2004) and 82% on two of the main sites in southern Ireland (1995-2004) were reported. Despite an encouraging upturn in the Flow Country population in 2005, to a level higher than that recorded in 1995, numbers are still well below 1988 levels. Scoters remain absent from Northern Ireland.

In 2006, 14 females were protected on RSPB reserves in the Flows but, for the second successive year, the number of young fledged was the lowest for 5 years. Nineteen pairs were found on the same reserves in 2005. The spring survey found 24 females, down from 29 in 2005, but only just below the five-year average of 24.6. Work to remove conifer plantations continued over the 2004/05 winter. The removal of 983 ha of plantation since 2002 will begin to help return catchments of some lochs to their original nature and reduce potential forest edge effects.

Has our work been effective?

It is too early to say until the next full national survey in 2007 but there are no clear signs of any increase in numbers from sample areas and no recovery in numbers or range in the Flows population has occurred. Both breeding and wintering populations continue to be threatened but measures are being taken to reduce these threats, at least for the breeding birds. It remains to be seen if work on offshore windfarm proposals results in protection of scoter wintering sites, though the RSPB’s input has undoubtedly improved the likely outcome for scoters. Until research into scoter ecology and conservation requirements in the UK is carried out, it is impossible to implement detailed, targeted management to benefit the species.

What do we plan to do next?

In partnership with the Wildfowl and Wetlands Trust and the statutory agencies, we plan to work on four priority topics:

  • Site designation: review current site protection status to determine whether further site designation is needed or appropriate, for both inland breeding sites and coastal moulting/wintering sites
  • Population monitoring: help to implement the monitoring strategies for breeding and moulting/wintering birds. Breeding counts will involve periodic national surveys combined with monitoring at a sample of sites
  • Breeding ecology: initiate a research project to identify site-based factors determining common scoter presence/absence and breeding success. This should inform subsequent management actions to increase scoter numbers and distribution
  • Origins of breeding and wintering birds: conduct an autecological study of the species on their breeding grounds

We will also:

  • Carry out a full national survey in 2007
  • Continue to assess potentially damaging developments and try to ensure that any such proposals are withdrawn or appropriately modified
  • Continue to minimise disturbance of scoter on breeding sites on reserves through fishery, visitor and forestry management
  • Continue programme of forestry removal from catchments of key scoter lochs


What are the constraints to achieving the targets fully?

Factors affecting breeding numbers have yet to be determined but are thought to be:

  • Eutrophication of breeding waters 
  •  Afforestation of surrounding areas
  • Shortage of invertebrate food due to competition with introduced fish
  • Introduced predators such as mink
  • Egg theft and human disturbance

Wintering and moulting flocks are threatened by a range of factors including:

  • Oil spills such as the Sea Empress in 1996
  • Over-harvesting of shellfish
  • Developments such as offshore wind farms, bridges and aggregate extraction

Acknowledgements

The RSPB has worked closely with a number of individuals and organisations during the year to further the conservation of the common scoter, in particular we would like to thank the Wildfowl and Wetlands Trust, Forest Enterprise and the many individuals, volunteers and private landowners who have helped common scoter during the year.

Last modified: 30 August 2007