I did a search, but I couldn’t find any threads dealing with this. Anyway, I was wondering why dogs get so vicious when the mailman/woman comes? I mean one day we were entertaining, and one of our guests was a mailwoman. Our dog, Shnookums, looked at this guest warily, but she didn’t do anything at first. We went outside to take in the cool breeze and talk. Then later in the evening, this person attempted to go in the house, and Shnookums was standing right at the glass door, growling and snapping at her. At first I used to wonder if it’s something in the smell of the glue on the envelopes or what, but on the evening we were entertaining, our maillady guest didn’t have any mail on her? Any guesses?
This is merely a guess.
Domestic dogs are still territorial animals who view humans as fellow pack animals. They use urine to mark the boundaries of their territory. Your mailcarrier friend unwittingly walks through these scent markers all day long. To your pet, the scent on your mailcarrier repesents an intrusion by multiple unfamiliar animal(s) as opposed to the one benign scent of a normal visitor. (Although dogs can get pretty aggressive at that as well).
Too funny.
My dogs have never liked people who attempt to come onto their property (yes, I said theirs, not mine!). This went for mail carriers, meter readers, tree trimmers dropping off flyers, etc. Eventually they get to know the regulars, and then it’s ok.
Our dogs have always loved the UPS guy though, go figure.
I wish I knew what it was about that mail carrier that superceded the uniform and bag, that’s wild.
The bag can upset dogs, BTW. It looks like some wierd appendage and freaks them out.
My story first, then my theory.
In college, I had an incredibly laid back dog. He was welcome at the liquor store where I worked. One day I was astonished to see Bowser take off like Cujo possessed towards the door of the liq. Without checking out what was up, I commanded him to stop, which he did. Only then did I see the object of his fury, the mailman had come in with the store’s mail, and had jammed himself behind the fully opened glass door to protect himself from the Bowz.
Later in his life, I had occasion to watch him in the back yard where he had a view of the street and front door. He would not react when people walked by or up to the door, except for mailmen!
My theory is that, when I went to school (and later work) Bowser would consider himself responsible for guarding the house. And every day, this person in a blue uniform would walk up to the house and mess around near the front door. Bowser would bark like nuts (probably scared shitless at first) with the result that every day the person in blue would (from Bowser’s perspective) flee the premises in response to Bowser’s bravery. Over time, the incredibly wussy Bowser would figure he really had one up on these scaredy-cat blue people.
Maybe I’m way off base. But that was the best I could come up with when trying to think like a dog.
Interesting theory Dinsdale, but the mailcarrier in the OP was out of uniform. I suspect that the cause is related to scent.
Great answers, y’all.
Yeah, Dinsdale, it is difficult, but oh-so-fascinating getting into a dog’s mindset. 
I have to wonder if there isn’t a certain amount of wuss factor going on with Shnookums too; however, one day we were outside with her, and the maillady had just walked up the steps of the house next door to us to put the mail in the mailbox, Shnookums went wild, broke loose from us, ran next door, and started climbing the stairs. She was growling and snapping at the frightened maillady. We got to her, grabbed her, and took her home. I was so shocked at her behavior. She wouldn’t come back to us when we called her. If we hadn’t grabbed her, she would have bit the maillady. Why would Shnookums want to get territorial with our neighbor’s property, land that she hasn’t been on or marked in any way?
evilhanz, that’s an interesting theory. I hadn’t thought about the scent thing. Maybe it’s all the confusing scents on the envelopes too. Dogs can’t really tell who’s approaching when they see one mailman/woman, but smell a plethora of people/dogs on him/her. Hmmm. But I’m still wondering about why Shnookums snapped at our maillady guest, when she didn’t have any mail on her and didn’t to my knowledge have multiple dog/people scents on her.
So EJsGirl, your dogs own property, hmmm? LOL! I think Shnookums feels the same way. 
I’m fascinated, though, about why your dogs love the UPS guy. It is interesting how dogs decide who to be vicious with. I mean, Shnookums barks but she doesn’t get vicious when the meter reader or when people bearing bags/boxes come by.
Oh yeah? Where did the OP specify that? And even if celestina comes along and says so at this point, who ya gonna believe – her or me?!
I interpreted the OP as saying that, as the evening was early, celestina’s guest didn’t have any male on her – yet!
I would be willing to bet a night in the sack that that UPS guy was carrying dog biscuits with him, for just this reason.
Dinsdale said:
"Oh yeah? Where did the OP specify that? And even if celestina comes along and says so at this point, who ya gonna believe – her or me?!
I interpreted the OP as saying that, as the evening was early, celestina’s guest didn’t have any male on her – yet!"
[giggle] Dinsdale! I am SHOCKED at you. [celestina wagging her finger at Dinsdale] Just what kind of lady do you think I am anyway? I’ll have you know that I can spell, despite my students’ best efforts to influence me otherwise. There’s a BIG difference between “mail” and “male.” In the matter of interpreting the OP, I’ll have you know that the party in question was held at my mother’s house, and she would definitely not go for any of her guests having any male on them in her presence. I trust that this has cleared matters up sufficiently.
Oh, the mailman just passed, and Shnookums was true to form again. I decided to try a little experiment so I held the mail he’d just delivered up to her, and she just sniffed and licked it as if it was no big deal. [sigh] I just don’t understand that dog.
Well, I’ve never seen him handing out treats, but you never know.
evilhanz, that is the most likely theory I have ever heard.
Our dog doesn’t like bags, funny or very large hats, dark sunglasses on strangers. It’s strange. Men are also more of a problem than women, but he’s always been protective of me, especially since the baby was born. He takes his job pretty seriously.
The fact that he weighs about 170 lbs doesn’t hurt his tough-guy image, even though he’s really a teddy bear.
My old dog had just the opposite reaction. He was great friends with our regular mail carrier. He ignored the substitue carrier that came by on occasion. But when ever he saw a UPS person he would go NUTS. he would even go charging across the lawn in as close to a rae as I ever witnessed from him if a UPS truck drove by.
My old dog had just the opposite reaction. He was great friends with our regular mail carrier. He ignored the substitue carrier that came by on occasion. But when ever he saw a UPS person he would go NUTS. he would even go charging across the lawn in as close to a rage as I ever witnessed from him if a UPS truck drove by.
Isn’t there some theory that says animals can “smell fear” on people, or at lease sense it?
Perhaps the mail lady in the OP, and the UPS person in evilskippy’s post are afraid of dogs and the dogs can tell.
Also, the OP subject may have a regular scent that Schnookums doesn’t like, or an aura about her that the dog can’t stand.
I mean, there are such things as “pet people” and “not pet people” aren’t there?
This is a very interesting thread, btw.
ZipperJJ, I’m glad you’re enjoying the thread. I am too, and I’m learning a lot. I love talking about doggies. I hadn’t thought of Shnookums smelling fear on folks. Still, the maillady guest at our dinner party is a pet person. She’s had pet dogs and cats before. I don’t know if at the time in question she had any. But we have at various and sundry other times had other guests who own cats and/or dogs too, and Shnookums just loves these folks to death. When they stop by, she doesn’t get vicious with them at all. I don’t know.
Could it be the uniform? Could it be a game to them?
I ask as my dog always barked murder at the mailman but it wasn’t the same vicious growl he had when he was really mad. It sounded mean but not as mean.
Also my neighbor was a mailman and he would hop up on the fence and stick his head over for my neighbor to pet him but if my neighbor was in his mail uniform boy did the dog bark at him.
Heres something a K9 cop I know told me:
A dog is in the house. Every day the mailman walks up to the door, and puts mail in the box. The dog pokes his head out the window or up to the screen door to see who’s out there. The mailman walks away. This goes on for awhile. Eventually, the dog is conditioned: "Hey, everytime I poke my head up to the screen, this stranger leaves. I must be king shit! This goes on, for years maybe. Then one day, the dog is outside, sitting in front of the front door. The mailman comes. He walks past the dog. He has to to get to the box. Now the dog is confused. Why didn’t he leave like he always does. Here I am, king shit, and the stranger walked right on by. The dog get’s so conditioned to this guy leaving everytime fido appears, that now he’s alerted that the stranger isn’t stopping. It’s an attack says the dogs 9 volt brain. And doggy fights back. Now the owners are confused: Why did my 10 year old dog bite the mailman (paperboy, milk man, meter reader, etc.)? It all has to do with conditioning and perceptions.
Agatha Christie (I think through her character Hercule Poirot) posits:
Every day, various people come to the door. Some are admitted inside, and these obviously have the approval and OK of the house owners. But this mail-person comes to the door every single day, and is NEVER admitted inside. He is obviously NOT welcome, and I should bark at him.
This theory works very well, I think. The UPS delivery man stops to deliver the package and talk to you, so while he may not be allowed in, he’s an OK visitor. The mailman however is clearly NOT OK.
Makes sense to me.
My father was a mailman for 27 years, and he actually had a dog on his route that would go around with him and sort of protect him from other dogs–figure that one out.
Great answers, all!
As far as games go, Markxxx, that’s an interesting theory, and in your dog’s case it probably does apply, but I don’t think Shnookums thinks she’s playing a game with the mailpeople. She plays games with her family all the time. She’s just being mean to the mailpeople.
pkbites & C K Dexter Haven, hmmm. Well, Shnookums is just plain spoiled rotten. Her perception is that she rules the house, even though she generally will back down when my mom orders her to do something. There might just be something to what you’re saying in terms of her thinking she can order the mailpeople to go away because she thinks that we don’t welcome them into the house. Still, I wonder how she can get the perception that we don’t welcome the mailpeople, especially when we accept the gifts they bring us everyday. I just wish I could ask Shnookums what’s going on in her brain so I can know for sure.
I just wanted to say that I’m really learning a lot and having so much fun getting your perspectives and your individual dog stories! Thank you for sharing and please keep the answers/theories/anecdotes coming.
I doubt it was the blue that was doing it. Maybe the look of the uniform, but not the color. Dogs as far as I know are colorblind.