1. Lake Kuş (Manyas Gölü), an important bird conservation area, was sampled in the summer, autumn, winter and spring of 1997, and the seasonal and spatial distributions of ostracods were investigated. Many of the taxa collected are useful indicator species for monitoring conditions within lake basins.
2. The findings suggest that the L. Kuş ecosystem is already substantially degraded. Pollution, coupled with extensive water abstraction for irrigation, have damaged the value of the lake, both commercially (as an inland waters fishery), and as an important site for wetland bird conservation.
3. This work shows that ostracod faunal analysis has value in the study of such sites, particularly where more formal physical, chemical and biological monitoring methods are inappropriate or unavailable. Copyright © 2001 John Wiley & Sons, Ltd.