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Rice cultivation has frequently been suggested to provide an important wetland habitat for waterbirds. However, in contrast to most other regions of the Mediterranean, the Camargue still has a substantial amount of surface area of natural marshes. Thus, we compared the abundance, species richness, and community composition of waterbirds in ricefields and natural marshes of the Camargue, during a one-year study. Based on surveys conducted at 4–7 day intervals in 1997–1998, our results suggest that natural marshes had substantially greater abundance of waterbirds, with ca. 99% of the individuals having been observed in natural marshes. Estimates of species richness and associated parameters further indicated that ricefields were clearly less rich than natural marshes. Although our results were rather striking for the Camargue, they may not be applicable to other regions because of the relatively high availability of natural marshes and differences in management of ricefields.

A low breeding success (36.5%) due primarily to nest predation by mammals, birds and reptiles has been found in the Woodchat Shrike Lanius senator at three study sites in Mediterranean France. Data collected for 3 years on natural and artificial nests showed no year, time, season or spatial effect on nest predation rate in this species. No particular spatial breeding strategy is used, breeding success being no better at any nest site currently used along roadsides or far from roads. With respect to nest predation pressures, the best breeding strategy for Woodchat Shrike should be to breed as early as possible at any suitable site within its territory. Nevertheless, the impact of high predation on the viability of the studied populations of this species cannot be fully explained by the large impact of habitat transformations (closure of open, bushy grasslands) on current day populations.