There is no standard answer to survival, because everything is relative to needs.
Raised in a desert area, water was always #1 on the list of things you need. But even that is mitigated if it is very cold out. You can freeze to death faster than you can die of dehydration.
While building a shelter is one thing, finding water where there is no surface water or snow is extremely hard. And even if you do, you need a container for it, or you are stuck at the water source.
It always made me laugh that porcupines were protected with the rationale that they are easy to catch and kill for food. Just peel it like an orange, I guess. Seriously, how do you butcher a porcupine? (Yes, it can be done, but they never teach that part.)
*how do you butcher a porcupine*
this guy gets off to an awkward start only hanging one foot, but then figures it out. Notice how much knife work is required, as opposed to a rabbit:
http://www.youtube.com/watch?v=Ktb4ZXveTQo
his part two video has a really good closeup on the guts, and what’s what:
http://www.youtube.com/watch?v=WWpoy6I0wZI
no-frills recipe:
ROASTED PORCUPINE
Leave porcupine whole. (After skinning and evisceration!). Chill meat to remove all fat. Parboil in simmering water to cover for 15 minutes with 1 teaspoon of baking soda.
Drain. Make your favorite stuffing. Stuff the porcupine and place on roasting pan. Cover with lid or foil. Bake at 325 degrees F. until meat is done, one to five hours, depending on the size of the porcupine.
http://prairiemary.blogspot.com/2008/01/what-to-do-with-porcupine.html