In the best fairy tale style, it menaces some birds, thus giving our heroine the traditional way to get help. (No, really, it's traditional. For heroes and heroines alike. The exact help you have to afford is variable, but you do have to do it. And they help more impressively than in Disney's Cinderella. I'm particularly fond of the one where the wolves eat up the wicked king and all his court for the hero.)
So, is it just a snake? Can I connect it to the major villainy of the story? Should I?
In a fairy tale proper, of course, this is not a problem. Things, people, monsters disappear with promptness and a total lack of explanation when they are superfluous to the tale.
For the moment, I think they shall be merely snakes. . . see how it works.