Is it normal i think the animals in shelters should be let out...

No it is not normal, nor is it humane.

Domestic animals can't adapt to wild conditions; not after millennia of breeding natural aggression out of them. Most would become diseased, starve to death, or be eating by actual wild animals; and they would live their last days in abject terror. Others would become a nuisance amongst humans who live rurally and would loose the respect they have gained in some societies as pets. That would lead to a decay in attitudes towards them and greater mistreatment.

Yes, your version of how it would be is very idyllic, but it is not very logical or realistic.

Animal shelters would be better off if people started being more responsible with their pets and have them spayed or neutered.

No. Introducing new species or subspecies into the wild at once in large numbers often screws up the ecosystem. It's just passing on the problem. Yes some of the animals you release might not be killed by wild animals, but if they survive they'll impact on the natural order of the ecosystem. You'll just create more problems by releasing sheltered animals.

Sheltered dogs do not know how to hunt because as puppies they were never taught. Their innate drive can only take them so far and a lot of them would just slowly starve. That's not humane at all.

I don't like the fact that those animals that are not adopted are often killed. It isn't fair. But releasing them does not deal with the problem without creating more problems which we can't deal with. For that reason it would not be a long term solution.

We're talking about a wider issue of morality here too. There are real terms for this which I don't remember, but I think that people tend to feel innately less responsible for something bad if it happens from their inaction as opposed to their action. If you take the inaction of allowing sheltered animals to take care of themselves you will feel less responsible when they inevitably die than you would if they were killed humanely in captivity. In reality there is no difference between the outcomes, but you naturally favour the inaction over the action because it reduces your feelings of involvement and thereby your guilt.

What to do with sheltered animals that will never be adopted is one of those problems without an easy solution, I'm afraid. What can be done by governments to lessen the problem in the future is:

1) Control the sale of young animals (puppies and kittens etc.) bred for profit from professional breeders by taxing them very highly so the price at sale of the animal to the consumer must be raised, thus incentivising the pet buyer into choosing to adopt an animal from a shelter which could be on sale for much cheaper. Thus more animals are adopted from adoption shelters reducing the sheltered population.

2) More rigorous guidelines for assessing people wanting to own an animal. Before my family adopted a dog from a shelter (costing us around £100) we had to have our home assessed by an inspector for safety. I think if animals bought from private breeders were also subjected to mandatory inspection and proof that they could afford to take care of the animal financially. The cost of this inspection would be expensive to the government, but subsidised by the taxation of privately bred animals. Thus less animals are given to shelters by ensuring the owners can take care of them.

3) Heavily subsidise private no-kill animal shelters. At the moment most of them rely on charity donations and the money raised from sale of animals. This means one of two things: either the price of animals from NKSs increases to keep up with cost meaning less animals are moved on or the shelter fails because the cost of feeding and keeping the animals is too high, in which case the animals musty be put down anyway. Subsidising NKSs will incentivise other shelters to adopt the "no-kill" philosophy and stop them from failing.

All of those things require more money and new taxes, which makes them difficult to start with. They also require governments to take action and avoid inaction, which makes them very difficult again. People who have the power to make change often decide to ignore and avoid making the difficult decisions.

You can't domesticate an animal to suit your own needs and then completely absolve yourself of responsibility when it turns out you then have to look after them.

If there are more animals than there are owners then we responsibly look after the animals we have and make sure they don't reproduce to a point where the problem persists.

I've used derivatives of the word responsible twice, but it really about accepting responsibility. I know it's easier to just dispose of a problem but take that to its logical conclusion and that's not the kind of world anyone would want to live in.

Other people have talked about how inhumane this is in terms of quality of life for the stray animals, so let's talk about practicality now.

There are about 600 million stray and homeless dogs in the world. Let's assume that there's about the same number of stray cats (if anything, I think there are probably more stray cats than stray dogs in the world, but it seems to be impossible to find a number on how many stray cats there are). If we give each cat and dog an average territory of 1000 square meters (a reasonable size for a lot with a small house, but a very small size for the territory of a wild dog), we need 1,200,000 square kilometers of forest, over twice the area of France.

Now, we can't release our animals in just any forest. We have to make sure that the forests we choose are reasonably hospitable and don't have any threatened birds or small mammals, because cats and dogs can drive these prey animals to extinction.

Only, as far as I can tell, there is no such place. If you haven't noticed, we're not dealing with an overabundance of forest habitat on our planet. We have far less forest than we used to, and what we have left is occupied my its natural inhabitants. Putting stray domestic animals there would displace the animals who already live there. I appreciate that you want to help animals, but what you're suggesting would be highly destructive.

Fortunately, there are programs to spay and neuter stray animals, as well as no cage/no kill shelters.

So you're saying that a domestic animal who is given food, water, shelter, and vet care should suddenly get kicked out to fend for itself? You think they are better off either getting killed by wild animals (or each other), starving, freezing and coming down with illnesses rather than being humanely euthanized?

Not to mention the massive number of them, it will strain the population of native animals through over hunting or competition.

These animals will likely escape from said woods or forest and make it back to civilization in no time, which will be a danger to people and their pets due to attacks and possible diseases.

I think it's a terrible idea.

Unfortunately, we have made many domestic animals like dogs dependent on humans. If they were let out of the shelters, they would become feral. Stray dogs are scavengers and there's nothing for them to hunt. Even if there was, humanity's domestication made them lose the ability to hunt for themselves. Mothers teach the young to hunt, and being that through generations we have pampered them with kibbles and such, they no longer need it. The same applies to other domestic animals.

Stray dogs are a threat to societies, especially in Asia and Eastern Europe. They can be very violent and kill people and other animals. They are also frequent carriers of diseases since they scavenge through trashbins.

Through the jungles wild and free...

http://en.wikipedia.org/wiki/Life_After_People