Ligorian mastodon
From Memory Alpha, the free Star Trek reference
Ligorian mastodons were large animals which are invisible.
In 2373, Jadzia Dax compared the Jem'Hadar's tracking of the cloaked USS Defiant through the Badlands by the ionization of its warp engines to the passage of a Ligorian mastodon through the forest: it could not be seen, but it made the leaves rustle. (DS9: "Blaze of Glory")
