Yes, so is the shrimp (even though the recipe I linked says cooked shrimp). Ceviche is traditionally all raw seafood.
from Wikapedia:
Ceviche, also cebiche, seviche or sebiche[5][6] (Spanish pronunciation: [seˈβitʃe]), is a seafood dish typically made from fresh raw fish cured in citrus juices, such as lemon or lime, and spiced with ají, chili peppers or other seasonings including chopped onions, salt, and cilantro.