Snakes are considered to be consumers, simply because they eat other animals such as rabbits, mice, and even some insects when they are very young. Examples of decomposers are bacteria as well as fungi. A consumer is simply an organism which feeds on other organisms, because it is unable to produce food for itself.
There are numerous types of organisms, including primary consumers, secondary consumers, decomposers, and producers. A snake would be an example of a secondary consumer, simply because it feeds on other secondary consumers. Primary consumers feed only on producers, such as plants that make their own food through a process known as photosynthesis.