While you can look up any of the SRD beast shapes from the compendium, in order to create a character sheet, which is what happens when you drag from the compendium, you must have GM control, or access to the API for the same purpose. If the GM has already created character sheets for the beast shapes and has given you access to these character sheets, you can then drag the character sheet to the map and be able to create/control the token for the character.