Generally, large birds and seabirds live longer than small birds. Albatrosses live so long that it is hard to calculate their survival rates - they can live longer than the metal rings that identify them, and probably longer than most humans.
Food chain. Definition. A feeding hierarchy in which organisms in an ecosystem are grouped into trophic (nutritional) levels and are shown in a succession to represent the flow of food energy and the feeding relationships between them. Supplement.
Food chain - Food chain length. 1  The food chain's length is a continuous variable that provides a measure of the passage of energy and an index of ecological structure that increases in value counting progressively through the linkages in a linear fashion from the lowest to the highest trophic (feeding) levels. [7]