The_Food_of_the_Gods_(1976) is a standard GIANT mutant animals on a rampage movie.
https://en.wikipedia.org/wiki/The_Food_of_the_Gods_(film)#Plot
GNAW: Food_of_the_Gods_II (1989) has even larger enraged animals running rampant.
https://en.wikipedia.org/wiki/Food_of_the_Gods_II#Plot
