Abstract:
Biologists are familiar with the thought that islands have unique scientific value as natural laboratories where the mainland species pool is reshuffled by differential immigration, extinction, and evolution to form new communities of fewer species. As material for studying these natural experiments, birds of the Channel Islands are of special interest. The reason for this interest is not that the birds themselves are unique: Channel Islands birds are far less distinct than those of the Galapagos (e.g., see Power 1980), and they are also less distinct than the Channel Islands plants that Philbrick (1980) has discussed. But birds are the most easily observed, best-studied organisms on the Channel Islands, and hence they are the organisms for which we have the most detailed information on ecological topics such as population dynamics, niche shifts, and competition.