Question

(04.01 mc)
in the ecosystem pictured below, notice that the flowers provide food for the butterflies, the butterflies are eaten by scrub jays, the scrub jays are eaten by snakes, and the snakes are eaten by eagles.

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use the picture and food - chain that is described above to answer the following questions.
part 1: describe what happens to the energy as it moves through each trophic level in this environment, and why this is happening.
part 2: suppose the producers begin with 200,000 j of energy. how much energy would be available for the scrub jay? describe how you would calculate this number.
part 3: the apex predator in this environment is the eagle. the population of eagles in this ecosystem is very small compared to the other populations. considering energy at each level, why are there fewer eagles than the other organisms? calculate the available energy for the apex predator.

Explanation:

Part 1: As energy moves through trophic levels, only about 10% is transferred to the next level. This is because most energy is used for metabolic processes like respiration, growth, and reproduction in each organism, and lost as heat.
Part 2: Producers have 200,000 J. Butterflies (primary - consumers) get 10% of 200,000 J = 20,000 J. Scrub - jays (secondary - consumers) get 10% of 20,000 J = 2,000 J. We calculate by taking 10% of the energy of the previous trophic level at each step.
Part 3: There are fewer eagles because so much energy is lost at each trophic level. If producers have 200,000 J, butterflies get 20,000 J, scrub - jays get 2,000 J, snakes (tertiary - consumers) get 200 J and eagles (apex - predators) get 20 J. With less available energy at the top level, the ecosystem can support fewer eagles.

Answer:

Part 1: Only about 10% of energy is transferred to the next trophic level as most is used for metabolic processes and lost as heat.
Part 2: 2,000 J. Calculate by taking 10% of the energy of the previous trophic level successively.
Part 3: There are fewer eagles because of low available energy at the top - trophic level. Available energy for eagles is 20 J.