The incidence, functions and ecological significance of petrel stomach oils

Recent research into the origins and compositions of the stomach oils unique to sea-birds of the order Procellariiformes is reviewed. The sources of these oils, most of which contain mainly wax esters and/or triglycerides, is discussed in relation to the presence of such compounds in the marine environment. A number of functions are proposed as the ecological roles of the oils, including their use as slowly-mobilisable energy and water reserves for adults and chicks and as defensive weaponry for surface-nesting species. suggestions are made for further research, particularly into physiological and nutritional aspects.