For those unfamiliar with this piece of history (or worthless trivia as some might say), there is an interesting reason why we have so many frogs.
The 1972 horror film, aptly titled "Frogs", was filmed at Eden. The house and surrounding area are the main locale. Without going into much plot detail (trust me, it truly is as bad as you can imagine, although I am sure some will find the tale of environmental caution relevant with our current events), numerous amphibians and reptiles were brought in for filming. Many of these frogs and toads escaped, and possibly were released, during filming.
Undoubtedly, many of our current frogs and toads are descended from these "famous" amphibians.
For more info, check out the IMDB page, and I believe the trivia section references the escape of of the frogs.
http://www.imdb.com/title/tt0068615/ I personally have heard the same tale numerous times locally.