Every outdoorsman, hunter, angler, hiker, should carry some basic survival gear to get you through a dark and lonely night should you find yourself unable to return to the truck or camp. Many of these items may be mentioned in other lists but I would like to do a list of specific things you may want to make a bit of room for. They are not heavy and you will be happy you have them if you need them.
There are 6 priorities to consider and you should have at least something to cover them all;
1. Signal for help. If you can get out of trouble before it becomes a survival situation, you are ahead. Cell phones are great if you have service or can text, A good signal mirror can be seen for miles and can signal ground service as well as aircraft. A small emergency road flare is good for getting attention and for lighting a signal fire too. Dont forget a good flashlight and some extra batteries. A Storm or Jet Scream brand emergency whistle - they can get someone's attention (rescue dog?) for a long, long way away. Many hundreds of yards. Your voice will be shot after a couple of minutes. You can blow the whistle all day long. I cut the back piece out of an old florescent yellow t-shirt and put it in my pack. It is very visible from the air when you wave it vigorously.
2. Build a fire. This provides you warmth, signalling, a way to boil and disinfect water, and makes you feel better as you sit near it to keep warm. I always have 3 ways to start a fire and some extra tinder to get it started if nothing is available around me. Storm proof matches in a watertight container, two Bic lighters in a Ziploc bag, and a ferrocerium rod if the others fail. Strike sparks into some Vaseline-soaked cotton balls and you will get it started.
3. Gather water. Either carry a full canteen or a large stainless steel bottle so you can boil water once you have collected it from a stream or pond. I keep a SS drinking cup nested over my bottle too. A small bottle of 2% Iodine will also help disinfect the water, 5 drops per quart or liter. I also have a new 3 foot length of fish tank hose to use as a drinking tube if needs be. Water is an absolute necessity.
4.Make shelter. Carry a lightweight plastic sheet or tarp to make a roof, wind break, or at least, wrap around you. Two plastic 55 gal drum liners can do the same and can be used for other things too. Don't forget a roll of cordage to use to tie it down or up or whatever. Even simple sisal cord will work, it just needs to be strong cordage. I do not like nylon because it comes unwound if you cannot melt the ends and can be tough to keep knots tight. Same goes with 550 Paracord. Put in a long sleeve t-shirt and a knit hat if it will get cold at night.
5.First aid. A good first aid kit should have at least one trauma bandage to deal with blood loss as well as bandages
for the other boo-boo's. Everybody needs at least a basic FAK. Look into building one of your own.
6. Food is a controversial topic because all the experts say you don't need food for several days but I wonder if they have ever tried it? When you haven't had anything to eat in many hours, it's an ugly feeling. I get an upset stomach and worse, low blood sugar too. A few meal replacement bars do not weigh that much and go a long way in making you feel better as you wait to hike out or for help to come. This will be up to you though.
This all may seem like a lot of extra stuff but it really isn't. A couple of extra pounds in your pack may make life a little easier once bad things happen when you least expect it.