The warm water method is fairly easy. You just hold the baby in warm water and gently stroke it they just relax and peacefully pass away under the water. Less messy and seems kinder than chopping heads off, lol.
Im not aware of any veterinary or wildlife organisation or experts that would consider drowning, which I assume is what you are meaning? As a humane method of euthanasia. In face most reputable organisations specifically state this is not an acceptable (and in many countries, legal) method of euthanasia. It might be less bloody than some of the other methods, but thats maybe thinking more about how easy it is for you, not the bird in question.
Please people, before you ever attempt to home euthanise a bird, do your research, check out reputable sites and scientific evidence rather than just peoples opinion (or if someone has a method you think is best, research it independently of the forums or websites where you were recommended it).
While gory and boloody at least the cervical dislocation methods, as far as I can tell are recommended by experts because they immediately sever any chance for the bird to be conscious and feeling.
Drowning, requires you to be under water and conscious, until you, having been unable to reach the top of the water to gasp in some air, are forced to breah in water. Anyone who has eaten something that went down the wrong way and the. Coughed their lungs out, or anyone who accidentally reathed in even a drop of water by mistake when swimming, will know that inhaling water is one of ghoe most horrible experiences, one your body instinctively reacts dramatically to. One of the worst ways to die in my opinion (and for context i love to swim, am not afraid of deep water oor of having my head under water and actually demonstrated as a child/young adult a new series of training methods for schools and swimming clubs. So my opinion that drowning would be a horrible death is coming frim someone who loves swimming and beung in the water,and feels perfectky at home there..... much like a duckling. I would never,ever drown one. If i were in an emergency situation where a duck or duckling was in a huge amount of pain or distress and no vet was available (or things were so bad that even spending the 40-60 mins driving from my rural home to a vet was too long), id use the cervical dislocation method if i knew i could do it well (which atm i cant)
Or probably use my air pistol to end things thru the area at the back of the head where you are supposed to kill them. That would involve blood and me inflicting obvious physical injury, and id ensure my air pistol was fully loaded with a fresh cartridge, and as it does 10 shots without reloading or cocking, that it wasfully loaded with shot, and id ensure i had it aimed right and id fire at least 3-4 shots all atonce and immediately if any sign the bird was conscious probably go for the eye next.
Disclaimer: Ive never done this, I have had vets euth birds, but if a vet was unavailable thats what i would do. I would not ever drown a duckling,ive seen and rescued drowning ducklings.
And its terrifying for them, if a bird goes quietly this me, i can only assume its too weak and tired to fight,NOT that it is not suffering.
Regardless of your reasons for having poultry, a humane death is the last and maybe most important service we should be giving those who have been our friends, our pets, our food, or even just our income.
Here is one of a number of articles where the suffering during drowning has been researched:
https://www.researchgate.net/profil...WQiLCJwcmV2aW91c1BhZ2UiOiJwdWJsaWNhdGlvbiJ9fQ