Humans are omnivores and therefore fit into multiple trophic levels of the food web. As primary consumers, humans eat plants and algae. However, humans also eat other animals, such as fish, amphibians, reptiles, birds, and mammals. Therefore, humans can be considered secondary, tertiary, or even quaternary consumers.
The specific trophic level of a human depends on their diet. For example, a person who eats only plants is a primary consumer. A person who eats both plants and animals is a secondary consumer. A person who eats other animals that eat other animals is a tertiary consumer, and so on.
Humans also impact the food web through their activities. For example, hunting and fishing can reduce prey populations. Clearing land for agriculture destroys habitats and displaces animals. Additionally, pollution and climate change can have negative effects on the entire food web.