A mnemonic (pronounced new-monic) is a device that is a learning tool used to help memorize things. Biologists often use mnemonics to help learn and identify the different calls a bird makes. It is difficult for humans to mimic the different calls of birds, so biologists will make up words or phrases to help them remember individual calls. For example, the Yellow-Billed Cuckoo has a very distinct call that is difficult to repeat. Instead of trying to mimic the bird, biologists have developed a mnemonic to learn and recognize the call.