A trophic level is a feeding position in a food chain. Every food chain starts with a producer. Producers are green plants and algae. They make their own food by photosynthesis, using light energy, and they are the first trophic level. All the biomass in a food chain starts with the producers.
Consumers get their energy by eating other organisms. A primary consumer eats producers, so it is a herbivore. A secondary consumer eats primary consumers. A tertiary consumer eats secondary consumers. The consumer at the top of a chain, with no predators, is called the apex predator.
In the food chain grass, rabbit, fox, the grass is the producer in trophic level 1. The rabbit is the primary consumer in trophic level 2. The fox is the secondary consumer in trophic level 3. Decomposers break down dead organisms and waste and return nutrients to the soil.
