In brooding them it's a diffence between dust and water lol. You can keep chicks in a cardboard box, bit there will be lots of dust. Dost ask me where they get it, but they do and they will make it AIRBORNE! Ahchoo...scuse me. With ducks you have to keep them in a plastic tote box and wash it out because of all the water they will mess.
When they are grown up not much changes. Dust and water, respectively. Speaking of... chickens do tend to less respectful of personal space. They are awl ways getting underfoot when I'm trying to move their tractor with my tractor. I have to STOP and WAIT for them to GET out the WAY(I wish my lil tractor had a horn...). When the ducks hear the engine, they get out the way first, then they watch the proceedings. So back to the water stuff...take it from a complete stanger(would I lie to you?),it's much more fun to watch ducks bath in water than chickens bath in dust...atchoo...scuse me.(also see gray text at bottom of my post)
Now I'm gonna try to answer some of your questions instead of soap boxing. I think I adressed water, yes? Good moving to numero dos, it's mostly the same,but ducks have slightly less potential to make each other bleed due to rounded bills, not beaks (shoulda been my name, darn). They have less tendency to ostracize the lowest on the pecking order, at least in my experience. Did you know I have a chicken that the others won't let out the coop? Coz they hate her? Well I do and now you know. Number three,diet. Duck tend to eat more green leafy stuff than chickens along with some clear liquid stuff known as dihydrogen monoxide... watching them dabble is a lot of fun too.
Friendlyness with me, they are the same as chickens. If you spend lots of time with them,they get used to being picked up. The difference comes when you kiss the back of their head and the ducks smells great, imo, and the chicken makes you...ahhht---hold it...I DON'T KISS THE CHICKENS! And the ducks only come runny around my feet when I actually HAVE treats for them, not just whenever they see me or any other big moving object(like a tractor). And the ducks are more distrustful of strangers than the chickens are. Makes you feel special when they cuddle up to you and won't go near your best friend or your mom.
Ease of taking care of is better in ducks because filling the pools don't count, you get a lot of enjoyment from it, and with ducks laying eggs in the morning, you only have to check for eggs once a day! Chickens lay all day and if you don't collect soon they will peck with sharp beaks and EAT their own eggs. Not that you won't go out to your ducks at least three times a day anyway....
Hope I've answered your questions and sorry for wasting your time by making you read this stuff.... good luck!
Edit: I would rate ducks 2 and chickens 5(and I'm reeeally generous there
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