"Ululates" is a verb that refers to the high-pitched, howling sound that some animals and people make. It's a dramatic word that's not commonly used in everyday language, but there are a few synonyms that can be used to describe a similar sound or action. "Howls" is probably the most common and straightforward synonym, but "yowls," "wails," "cries," and "moans" could also be used depending on the context. In some cases, "screams," "shrieks," or "yelps" might work too. While these words don't have exactly the same connotation as "ululates," they can convey a similar sense of sorrowful or fearful crying out.