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Eradication of the Ruddy Duck Oxyura Jamaicensis in the Western Palaearctic: a Review of Progress and a Revised Action Plan for 2021–2025

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Eradication of the Ruddy Duck Oxyura Jamaicensis in the Western Palaearctic: a Review of Progress and a Revised Action Plan for 2021–2025 Strasbourg, 3 December 2020 T-PVS/Inf(2020)11 [Inf11e_2020.docx] CONVENTION ON THE CONSERVATION OF EUROPEAN WILDLIFE AND NATURAL HABITATS Standing Committee 40th meeting Strasbourg, 30 November - 4 December 2020 __________ ERADICATION OF THE RUDDY DUCK OXYURA JAMAICENSIS IN THE WESTERN PALAEARCTIC: A REVIEW OF PROGRESS AND A REVISED ACTION PLAN FOR 2021–2025 Report prepared by Wildfowl & Wetlands Trust (WWT) T-PVS/Inf(2020)11 - 2 - CONTENTS1 SUMMARY .................................................................................................................................................. - 3 - 1. INTRODUCTION ................................................................................................................................. - 5 - 2. METHODS ............................................................................................................................................ - 5 - 2.1. Questionnaire ................................................................................................................................. - 5 - 3. RESPONDING COUNTRIES .............................................................................................................. - 6 - 4. STATUS OF RUDDY DUCKS IN THE WILD ................................................................................... - 6 - 4.1. Numbers of non-wintering and breeding ruddy ducks .................................................................. - 6 - 4.2. Numbers of ruddy duck controlled ................................................................................................ - 8 - 4.3. Status of ruddy duck in Belgium, France, the Netherlands and the UK ........................................ - 8 - 5. STATUS OF RUDDY DUCK IN CAPTIVITY ................................................................................. - 11 - 6. IMPLEMENTATION OF THE ACTION PLAN FOR ERADICATION, 2016–2020 ...................... - 12 - 6.1. Actions concerning eradication of ruddy duck in the wild .......................................................... - 12 - 6.1.1. Progress against Target 1 ..................................................................................................... - 12 - 6.1.2. Progress against Actions 1 to 4 ............................................................................................ - 13 - 6.2. Actions concerning ruddy duck in captivity ................................................................................ - 17 - 6.2.1. Progress against Target 2 ..................................................................................................... - 17 - 6.2.2. Progress against Actions 5 to 7 ............................................................................................ - 18 - 6.3. Actions concerning public awareness, reporting and international co-operation ........................ - 21 - 6.3.1. Progress against Target 3 ..................................................................................................... - 21 - 6.3.2. Progress against Action 8 .................................................................................................... - 22 - 7. CONCLUSIONS ................................................................................................................................. - 23 - 8. ACKNOWLEDGMENTS ................................................................................................................... - 26 - 9. REFERENCES .................................................................................................................................... - 26 - 10. ANNEX. ACTION PLAN FOR THE ERADICATION OF THE RUDDY DUCK IN THE WESTERN PALAEARCTIC, 2021–2025 ...................................................................................................................... - 27 - 11. Appendix 1: Additional information provided by each responding country ................................... - 30 - 11.1. Full questionnaire .................................................................................................................... - 30 - 11.2. Simplified questionnaire .......................................................................................................... - 41 - 12. Appendix 2: The questionnaire distributed in 2019 to assess progress against the 2016 –2020 ruddy duck eradication action plan ........................................................................................................................ - 42 - 12.1. Full questionnaire .................................................................................................................... - 42 - 12.2. Simplified questionnaire .......................................................................................................... - 51 - 1 Recommended citation for report: Cranswick, PA, & C Hall. 2020. Eradication of the Ruddy Duck Oxyura jamaicensis in the Western Palaearctic: a review of progress and a revised Action Plan for 2021–2025. WWT report to the Bern Convention. - 3 - T-PVS/Inf(2020)11 SUMMARY The Ruddy Duck became established in the wild in the Western Palaearctic following escapes from wildfowl collections. It is considered the greatest long-term threat to the White-headed Duck. The obligation to eradicate alien ruddy ducks is recognised by many international conservation conventions and agreements. An eradication plan has been developed under the Bern Convention and is updated every five years. A questionnaire was sent to 48 Western Palearctic countries to assess the status of Ruddy Ducks and progress against the 2016–2020 eradication plan. Some 19 Contracting Parties, including most of those with significant numbers of Ruddy Ducks currently or in the recent past, reported for the period summer 2016 to summer 2019. By 2019, there were around 250 Ruddy Ducks in Europe, with continuous presence in only four countries. France holds the largest numbers. Wintering totals declined from 256 in 2010/11 to 94 in 2018/19. France also reported the highest number of breeding pairs – fewer than 30 in 2019, a decline from the peak of 40– 60 pairs. Numbers in the Netherlands have remained above 50 birds since 2011/12, increasing to 81 in 2018/19. Breeding pairs also increased recently, from a minimum of four in 2017 to a minimum of 12 in 2019. In the UK, wintering numbers declined from 189 in 2010/11 to 23 in 2018/19. Breeding pairs decreased from nine in 2012 to two in 2019. Neither pair was successful in 2019, the first time in 50 years that breeding has not occurred in the UK. In Belgium, numbers of Ruddy Ducks are highest during the summer months and fluctuate between years. Peak numbers have generally remained below 20 individuals (32 were recorded in 2016), but have generally declined, with only eight in 2019. Only a single pair of potential breeding birds was reported each year, with none seen in 2019. Sightings of single birds were reported by every year by Switzerland and the Slovak Republic, whilst Czech Republic, Denmark, Iceland, Poland and Portugal all reported sightings of very small numbers at some point. No Ruddy Ducks were reported by Andorra, Bulgaria, Croatia, Latvia, Liechtenstein, Malta, Norway and Spain. Of the 29 countries that did not respond, birds have previously been recorded in Austria, Finland, Germany, Hungary, Ireland, Italy, Morocco, Sweden and Slovenia. Monitoring schemes to survey Ruddy Ducks in the wild are considered adequate in the majority of countries, although less so for breeding birds compared with non-breeding, mainly due to a lack of coverage of potential breeding sites. Eradication programmes of resident Ruddy Duck populations were undertaken in Belgium, France, the Netherlands and the UK. In France, 100–200 birds were culled each year during the period. Eradication in France has two main difficulties: birds wintering on Lac de Grand-Lieu are extremely wary and difficult to approach, and birds disperse widely during summer making them difficult to locate. In the Netherlands, 23 were culled in 2017/18, and fewer than ten in other years. Barriers to controlling birds include: a lack of cross-border cooperation between provinces, each determining its own commitment and resources; eradication is a low priority among site managers of nature reserves; difficulty accessing Natura 2000 sites to control birds; and the anti-hunting sentiment amongst a large proportion of the public. The long-term eradication programme in the UK has reduced the number to fewer than 25 birds. Most are isolated, and the species may be functionally extinct in the wild by the end of 2020. The target date for eradication has been revised to 2023, as it is possible that some birds may live for a number of years and immigration from mainland Europe could be a potential problem. T-PVS/Inf(2020)11 - 4 - An eradication programme is in place in Belgium. The success of the programme is highly influenced by movement of birds from neighbouring countries, particularly the Netherlands, with most birds recorded in the north of the country next to the border. Several countries operate reactive control programmes, quickly targeting individuals that arrived from outside the country. One in Portugal was the only bird culled during the period outside Belgium, France, the Netherlands, and the UK. Few countries were able to report with certainty how many Ruddy Ducks are held in captivity, with only one (Liechtenstein) claiming to completely monitor numbers. France, Norway, Poland, Portugal, Slovak Republic, Spain and the UK
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