Do you need a rooster to raise chickens?

Do you need a rooster to raise chickens?

 Although a rooster is not a necessity for chickens to lay eggs, the rooster does provide some protection for the hens especially if they are free range. I have raised chickens with and without roosters and I do find they are less prone to hawks and some other predators. Basically, the hens are less nervous and more relaxed if they know a rooster is looking out for them. The rooster will watch over his hens and warn them when danger is nearby and in some cases will try to physically protect his hens if the threat is not too overwhelming. It really depends on the personality of the rooster. I have seen some roosters cut and run with the rest of the hens, while others will stand their ground no matter what the foe may be. This is especially true of Bantam roosters who seem to have more fight in them than most. It should also be noted that Bantam hens make better mothers and if you want to hatch an egg put it under a Bantam hen.
    The rooster will also help them find food but sometimes this is more a ploy than an actual benefit to the hens. As the rooster will use a food call to get close enough to the hens in order to mate with them. This said the rooster remembers places where there is plentiful food and will lead a flock time and again to such a place in order to take advantage of it.
    If you raise your hens without a rooster invariably one of the hens will assume the role of rooster. This is nature's way of filling a gap and is part of the pecking order but I find that a real rooster does a better job than a hen pretending to be one. A hen pretending to be a rooster will also be more concerned with deciding who is boss and who gets the most food than protecting the flock. A rooster that finds food will make sure that all the hens know there is food nearby, whereas a hen pretending to be a rooster will simply try to keep the food to herself.

Chickens starting to set? Or how to know when a hen is ready to hatch eggs.

I have been finding marble size eggs in ckicken run. My father tells me that it is an indication that the hen that layed the egg is ready to start sitting on the eggs to hatch them.

A hen that is broody may also be a sign the hen is getting ready to set. Broody is when the hen is reluctant to leave the nest when you are collecting eggs. She may also peck at you if you try to reach under her and cluck at you strangely as if she did not want to be disturbed. This indicator varies from breed to breed, in some breeds are more broody than others.