A salt marsh food chain includes cordgrass, marsh snails, shore crabs and herons.
The table shows the biomass of the first three trophic levels in one area of the salt marsh.
| Organism | Trophic level | Biomass in kg |
|---|---|---|
| Cordgrass | Producer | 40 000 |
| Marsh snails | Primary consumer | 3 200 |
| Shore crabs | Secondary consumer | 400 |
The efficiency of biomass transfer from the shore crabs to the herons is predicted to be the same as the efficiency from the cordgrass to the marsh snails.
Calculate the percentage of the cordgrass biomass predicted to be transferred to the herons.
Show your working.
103 exam-style questions on AQA GCSE Biology 7.4 Trophic levels in an ecosystem, covering 7.4.1 Trophic levels, 7.4.2 Pyramids of biomass, and 7.4.3 Transfer of biomass. Each one has a worked solution and a mark scheme showing where the marks go.