by Judit Szabo, Science Officer of EAAFP Secretariat
The Scaly-sided Merganser is a beautiful and rare duck breeding in the Russian Far East, the Democratic People’s Republic of Korea and China and wintering mostly in China and in the Republic of Korea. To halt declines, the Scaly-sided Merganser Task Force was established in 2010 and has been very active under Coordinator Diana Solovyeva and recently-appointed Chair Lei Guangchun. Following an initial workshop in 2010, experts returned to Vladivostok for a second workshop in 2015 September to finalise the Scaly-sided Merganser Single Species International Action Plan. The workshop started with national reports from China (by Zeng Qing), Republic of Korea (by Nial Moores) and Russia (by Diana Solovyeva). Unfortunately experts from the Democratic People’s Republic of Korea were unable to attend. To develop the Action Plan, after a review of status and trends in breeding and wintering populations, with the expert facilitation of Peter Cranswick from WWT, we discussed threats. The current population estimate for China is around 3,500. However, birds are still threatened by illegal hunting and disturbance by tourists. Dams have removed habitat in both China and in the Republic of Korea – birds never use river sections upstream as the water becomes too deep to catch fish and gravel bars (boulders and islands) get inundated so mergansers have no place to roost. In the Republic of Korea the wintering population is 150-250 birds depending on the severity of the winter and how wet the previous summer was. Threats here include sand extraction from rivers, bridge building, and disturbance from cyclists on small cycle paths near rivers as well as photographers. Collision with power lines can also kill mergansers. In Russia there is one major breeding population in Sikhote-Alin with 1,730 pairs and two smaller ones on the other side of the Amur River. Threats in Russia include birds getting shot by hunters (mistakenly or otherwise) as well as being disturbed by people on the rivers. Some birds also die in fishing nets.
The crucial part of any action plan is the actions, their scale and their feasibility. The most important actions to focus on in the next few years are: 1) Consulting with authorities about problems with current dams and how and where to put new dams in China and ROK, 2) Stopping spring hunting of Anatidae at the breeding sites in Russia, 3) Raising awareness among fishermen about the mortality of mergansers in fishing nets in China and Russia. Also, we need to minimize human disturbance at all times of the year – at brood rearing, moulting and wintering sites. On the second day of the meeting we continued to discuss national action plans and the best approaches to hold national meetings with stakeholders.
Diana gave a very interesting review about the impact of nest boxes on the breeding success and how to best avoid nest predation. We learned about captive breeding from Johnpaul Houston from Blackpool Zoo in the UK (http://www.blackpoolgazette.co.uk/news/community/community-news/zoo-expert-to-travel-to-save-rare-species-1-7462508) and discussed ways captive breeding can help conservation of the mergansers in the wild – for instance correct aging of birds based on plumage, possible individual identification of males based on plumage patterns and genetic studies on isolated wild populations.
The workshop was followed by a field trip to Kievka River where we witnessed the nest box-building guru – Sergey Vartanyan in action, both building and placing nest boxes on trees. Spending about six hours in a kayak on the river, we observed over 50 mergansers in groups of up to 11. It was nice to see all the young birds with their parents – indicating the species is on the way to recovery.
Visit EAAFP Scaly-sided Merganser Task Force page