Declining Ruff Philomachus pugnax populations: a response to global warming?

Author: Zöckler, C.
Date Published: January 2002

Wader Study Group Bulletin  97

Ruff breeding populations have declined widely and in all habitats across temperate Eurasia. Of an estimated population of 2.2-2.8 million birds, 98% are now confined to habitats in the Arctic tundra. Only 8,000-14,000 females still breed in wet grassland habitats in Europe. Although drainage and agricultural intensification have damaged or destroyed many grassland habitats, they do not explain why Ruffs have continued to decline even where habitats have been improved and in places where other wet grassland species are stable or increasing.
The hypothesis that the problem is limited to one or a few flyways is not fully supported by the available data though there is some suggestion of a greater decline in W Europe/W Africa populations. For most regions, systematic monitoring data are lacking.

Nevertheless the emerging picture is that the population has shifted northwards and eastwards and has retreated from the wet grassland habitats formerly occupied along the southern edges of its range. It is suggested that the causes are probably of a global nature and may be linked with climate change. It is unclear whether the total population has declined or only shifted north and east. More co-ordinated and systematic monitoring of breeding and wintering populations will be necessary before a full understanding of these changes can be reached.