The event description points out that the students only need to know common names of the birds. Just to clarify - does that mean "Crow" is sufficient and they do not have to write "American Crow" for the answer?
In this case, "common name" is meant to contrast with "scientific name." Students should know the full common name of all the birds. This will especially help with identifying the owls and woodpeckers. For instance, depending on the question, answering "crow" or "cardinal" might only count as a spelling error, since those are the only birds found in the region with those common names. Answering "woodpecker" or "owl" could count as an incorrect answer since many different birds have those shortened common names.
Students are allowed to have the rules sheet which has the full common names of all birds.