Yes, they automatically know, you see, they have this thing, and it's located right above their mouths (that's the end with the pearly whites, not the end the stinky stuff comes out), and right above those pearly whites there lie two orifices,, Believe it or not, they can actually breath through those orifices. And as they breath (they breath air, that's what's in the atmosphere), it's oxygen-bearing and we use it pretty regularly ourselves, it has an atmospheric pressure of 14.7psi at sea level, but drops as you rise in elevation (elevation means higher, ),that's what makes flatlanders huff and puff when they come to the hills here (please don't). Anyway, as they process this oxygen-bearing substance, they also ingest every bit of scent that they come across. Sometimes, when in the pheasant field, that means they might smell a pheasant. When they smell a pheasant and blood, or a pheasant with broken skin, they, believe it or not, ( and I am talking about all hunting dogs, not just mine, although they are brilliant and sometimes seem magical), they can process that and discern if the bird is wounded, or not. How else can they bring you a wounded bird, instead of getting on the trail of the next bird you would like to flush and letting the wounded one run off? (Maybe yours do, sorry for your rotten luck, I can recommend a great spaniel kennel where the dogs actually have a good smelling thing).So as they process all this information, with some training that we do, little things like "bird down" drills, over time, they come to know what you expect of them. What I expect is that wounded bird in my hand and I don't care how many healthy ones fly away in the process. Now, my dogs are pretty good at it, not as good as some I have seen. The guys who have better ones help me bring my game along. Kind of like when I tried to give some basic info to a rookie on how to read a dog food label and a certain person jumped on one sentence that I wrote and made me "wrong" (in his mind). Kind of like how I used to tell anyone on this forum who asked, where they could have a good hunt. (those days are over, had to deal with too many people like you as a reward for my effort). Kind of like the crap you all gave me for advising someone who accidentally killed a hen to do what you would do if a kid was watching. so, anyway the dog uses that sniffy thing to discern a healthy bird from a wounded one. Kind of like sharks in the water. (They are a predatory, salt-water fish, found in the oceans of the World. (Oceans are large bodies of salt water). Then they track that bird until they either run it down, or, less likely with a good dog, they lose scent. It happened to me last Sunday because as it gets hotter, and dryer, that sniffy thing becomes less effective, and the dog has more trouble using those magnificent orifices. So yes, my dog lost a bird, (jump on that sentence, all you wisenheimers), but it don't happen often.
As for your question regarding a bird someone else wounded, see above.
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