A spider is classified as a consumer. In the ecosystem, consumers are organisms that cannot produce their own food and instead rely on other organisms for nutrition.
Spiders primarily feed on insects and other small animals, which they capture using their web or by ambushing them. This predatory behavior places them in the role of primary consumers in the food chain. Unlike decomposers, which break down dead organic material and recycle nutrients back into the soil, spiders obtain energy by consuming live prey. Thus, while they play a vital role in controlling pest populations, they do not engage in the decomposition process. Overall, spiders are an essential part of the food web, functioning as predators that help maintain ecological balance.