The black footed ferrets keeps one population from expanding too wide by eating them and yet lets other animals survive by letting predators eat them. Every animal is actually important to the ecosystem. Because if one organism fails, then the rest start to fail too.
Example:
Coyotes --> Black-footed Ferret --> Prairie Dogs --> Grasses
If one of the organisms in the food chain above fails, the rest of the food chain will all go extinct.
Example:
Coyotes --> Black-footed Ferret --> Prairie Dogs --> Grasses
If one of the organisms in the food chain above fails, the rest of the food chain will all go extinct.