What wild foods?

A good book to get is "Food for Free" by Richard Mabey.  Now seems to come in a more sensibly pocket sized Collins Gem edition, clicky...

Fishing depends what for and where.  In the sea you can go for whatever you want, on rivers with permits it's rather different!  I recall a particularly good meal on a paddling trip of coley we cooked on open fires on the beach in Shetland.

Pete.

Look What We Found do some really tasty ready meals that are a doddle to prepare (immerse in boiling water for around a minute).  You can get them from Sainsburys, Waitrose and Aldi have started stocking them too. 

I still have one packet from last year; a Cumbrian Lamb Hotpot.  My packets are just plain but the recent ones I've seen have stickers on them (so the water might need chucking away).

It is probably worth taking something like this alon just in case you fail to catch anything wild. 

Hunting for game (rabbits etc) is remarkably skilled - even with a gun - and regulated so I wouldnt really bother.

Freshwater fishing is also skilled and regulated.

At the right time of year, picking berries as you go along is a pleasure (fresh stewed blackberries are a real pleasure) and going "wild" on the sea shore or at sea can be very rewarding - a tin bucket with a foil lid filled with just picked mussels and and half a litre of sea water over a fire can produce a moule marinare the way it should be.

you pick/kill want you are going to eat there and then pretty much - storage issues should never be a question.  If there is too much so you have to store it, you shouldnt have picked or killed it in the first place.

Another vote for 'Food for Free', which is an excellent reference for all things wild and edible outdoors. I used to pick buckets of blackberries as a kid, and had no idea there were so many other things that could be picked and eaten. Head for the Arctic, and virtually everything that grows is edible, or at least non-poisonous... but the further south you head, the greater the number of non-edible and poisonous things there are.

I once met a poacher high in the North Pennines who said he would never kill anything that he wasn't prepared to eat. He also told me that fox tasted absolutely disgusting! The old Gypsy recipe for baked hedgehog involves rolling the beast in a ball of clay and baking it in an open fire. Crack it open, and the prickles come away with the clay, leaving the flesh ready to pick at. Never got beyond freshly road-killed pheasants myself!

For some reason, late last year, I had a super-abundance of seafood eaten live, straight from the sea. This included raw fish straight off the hook, octopus chopped into bits while still alive, and molluscs plucked living from their shells, for immediate consumption. The most disgusting items from that epic feat of endurance included jellyfish and a fish stomach!

Frankly... I'd stick with the fruit, nuts and vegetables!

PS for most people the "wild" bit in wild camping refers to the fact that you are not using a camp site, and it usually involves "wild toileting" (there are useful books and leaflets about this). For food we just eat what we bring. Which last time was wine, Irn bru (not for Pete or me ), crisps, instant couscous with sausages, sticky toffee pudding, instant custard, pancakes, etc....

Roos

Jeez! Worried about rabbits?!! They are vermin and IIRC it is actually the landowner's responsibility to keep numbers down. Trust me if you have permission of landowner you can take as many as you want. There is a reason for the "breed like rabbits" phrase. The small, newly born rabbits you see early spring starting to fend for themselves are the large rabbits breeding in a matter or months or even weeks later. Seriously each rabbit is capable of many litters in a year so you shouldn't worry about taking an adult rabbit. I'm not even sure if young even needs a parent if that parent and the young is out of the warren. They kind of fend for themselves from very early on!!

LLWF foods keep. I have taken them on hot days and not eaten them for a week during which they got hot during the day and never cooled. They are sealed when hot so supposedly keep out of the fridge without making you ill.

You can keep things like salami and pepperoni ok for up to a week. Well I have anyway. Oatcakes are long life and I take primula "cheese". Unopened it keeps for a while even when not refridgerated IME. Once opened I generally eat within about 2 days. Dehydrated and wayfarer type foods keep well too.

Foraging for all your food is next to impossible and I'd say totally impossible if you want to actually backpack. If you read Book of the Bivvy the author actually recommends never carrying more than a couple of days food. The argument being that the extra distance in the UK needed to walk out to a shop for restocking is less than the effort of carryinga lot more weight to not need the re-stocking. Not sure how right that is out of the UK though.

Adders - Only an issue if you like to sleep in places they like to sleep in. They are not likely to attack you but more likely to avoid you. They know you are around before you know they are. however in some areas you can end up waking with adders who hav decided to sleep next to you. Not common but I have heard stories of a herpetologist who often sleeps out on snake surveys only to wake up with some adders next to him. He survives still!! They are not agressive in almost all situations and for a fit, healthy adult unlikely to do that much harm really even IF it bites you. Bear in mind the venom is needed to hunt and I believe not for defence as it is not fast acting. You might get a bite though but I believe it is unlikely to use it's venom. I could be wrong of course as I am half remembering what I've been told by a snake expert in the past.

Boars - IIRC they are in the south east and all the way across to South Wales in parts. Some pockets a bit further north and perhaps midlands. However there might be some boar farm escapees anywhere there are farms I guess. They are 30 plus MPH, 3/4 of a tonne of pure muscle and bone. They are much quicker than you and most likely know you are there before you know they are around. Mothers with young can be dangerous. Also the boars I believe can be bad tempered. However I doubt you'll come into contact in most areas. If you do get attacked, I guess it is tough!!

I have heard that in scotland at certain times of the year capercaille attack walkers. I hope that doesn't  give you nightmares!!!