How is the amount of available energy change as energy moves up the food chain?

As energy moves up the food chain, the amount of available energy decreases due to the inefficiency of energy transfer between trophic levels. Typically, only about 10% of the energy from one level is passed on to the next, while the rest is lost as heat through metabolic processes or used for growth and reproduction. This results in fewer organisms at higher trophic levels and a decrease in biomass and energy availability. Consequently, apex predators have less energy available to sustain their populations compared to primary producers.