The Bible never mentioned dinosaurs but we keep finding their bones. What happened to them?
The word "dinosaur" did not exist at the time of the King James version of the Bible (1611) - dinosaurs had not been discovered by modern science. So, in that translation at least, you won't find the word.
However, the Bible DOES make mention of large animals - behemoth and leviathan are two major ones, both mentioned in the book of Job. Behemoth has a tail like a cedar tree! Some have suggested this animal might be a hippopotamus, but does the tail of a hippo remind you of a cedar tree? On the other hand, tails of many dinosaurs are relatively thick.
Several possibilities exist as to what became of dinosaurs. Lots of species have become extinct, such as the dodo bird. We in fact often hear of the concern that modern species may become extinct. So, the fact that dinosaurs disappeared is not so unusual.
One possibility is that they became extinct due to climate changes after the flood. There may have been other changes, such as changes in their food supply, after Noah's flood. Some flood models include major geologic changes at the time of the flood. The recent formation of a canyon following Mt. St. Helens' eruption points out that geologic formations that were once thought to form only over long periods of time, in actuality may form very quickly. So, there could have been drastic changes to the habitat of these animals, which led to their extinction.
Re: QA - 587