Help With Boiling and Freezing Crab

We recently caught some crab at Westport, WA and boiled them until they turned red, then cooled them, then put them in freezer bags and put in our freezer. After we put them in the bags we noticed a yellow liquid which later (within 5 days) turned black. What has happened? Are these still safe to eat. They are the whole crab, we didn't clean them...we were told ok to boil and freeze whole and clean later.

Put your mind at rest! It sounds like you did everything right! The discoloring of the liquid left in with the crab is normal after boiling and then freezing crab whole. This happens to us, too. Sometimes there is light, dark brownish coloring in the liquids to even greenish tones.
Keep in mind that because you have boiled and frozen them whole the crabs still have their innards. This discoloring of the liquid is discolored from them being intact as well as still having their crab butter inside the shells.
This, again, is normal after boiling and freezing before cleaning the crab. When you decide to have crab dinner, thaw the crabs out, (makes it easier to break them down when cleaning them if they aren't frozen), then clean the crab under cool running water. This liquid will be washed away. After this process you are good to go to steaming them for dinner!
With this all said, Congradulations! And, Enjoy your crab catch!