He is not required to take a picture of the dog in order for Animal Control to do their job. Essentially, if he calls Animal Control three separate times complaining of this dog, then they are required by law to come out each time and investigate.
If the Animal Control officer finds evidence that the dog has been at large each of those times (and from the sounds of the owners, I am sure this is very likely), then Animal Control has the authority to pick up the dog.
Whether or not the dog "wanted to hurt" him is irrelevant. The dog was at large and not secured by its owners and if was close enough for him to hit it with a stick, then it was too close.
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