The term for the percentage of energy passed up each trophic level is called trophic efficiency. This efficiency typically ranges from 10% to 20%, meaning that only a fraction of energy consumed at one level is available to the next level. The loss of energy primarily occurs due to metabolism and heat production. As a result, higher trophic levels tend to have fewer individuals and require larger habitats to obtain enough energy. Consequently, the structure of ecosystems is deeply influenced by these energy transfer dynamics.