You are here:

Canine Behavior/Rescue Pit Mix/Weimaraner's Sudden Aggression


Thank you so much for your time and I will definitely rate your reply.

In August, my boyfriend and I rescued our 1.5 year old pit/weimaraner (we think) from a shelter. We know she was fostered but have no details.

Since we adopted her, she lives with my boyfriend and his two roommates.  She’s been very dependent on myself and my boyfriend – stays within about a foot of either or both of us at all times – and was indifferent to almost everybody she’s met.  She’s never been “aggressive” toward anyone, just didn’t bother interacting with anyone else.  She’s not aggressive with other dogs, except when they’re in her house – which we’re aware of and keep under our surveillance.  She also attends doggie daycare every weekday because all of us work long hours.  The daycare has said that she’s very sweet to other dogs and the attendants. She’s been to introductory training and knows sit, stay, paw, and come.

Often times there are about 3 to 6 people at my boyfriend’s apartment – him, his two roommates, another girl, and me – who have all walked, fed, and played with Nola.  Until about a month ago, she didn’t have any problems except maybe laziness. She lays around most of the time and loves to pretend she's a 50 lb lap dog.

Then a month ago, she snapped (not bite, just like a “warning” snap with no growling) at one of the roommates.  We thought she was sleeping on the couch, but he said she was looking right at him and snapped at him (even though she’s lived with him and interacted nicely with him for 3 months.)  She then did the exact same to the other regular girl when she leaned to pet her – she is there very often and has even lain on the couch with Nola on many occasions, and then finally she snapped the exact same way at the third roommate when he stepped near her.  Each time is when she’s laying down, awake, calm and quiet while we’re watching TV.  It could be the approach is bothering her, but it’s a scenario that has happened daily for the past 3 months and we cannot figure out what has changed.

I know she’s fairly new to the house, but we’re concerned that we’re doing something to upset her.  It’s very strange that the “aggression” is toward people that she’s generally been very comfortable with. Does any of this sound like something you’ve heard of before?  Is there a way that that we can help her interact with others?  She’s already been introduced to these people with no aggression, so now we’re even more worried about her meeting new people.  Any insight would be much appreciated!  

We love her very much and she’s so sweet 99.9% of the time – we just want to make sure we’re addressing the situation.
Thanks so so much!

ANSWER: Progression of aggression:  dog growls; dog lunges while growling; dog connects (leaving bruise); dog connects (leaving scratches); dog connects (leaving tooth marks); dog connects (leaving serious bite).  Dog can actually stop warning (growling) and escalate to full out attack (grab, bite seriously) at fully developed stage of active aggression.

A dog that "snaps" when lying down in a state of rest is possibly reacting with a conditioned fear response acquired in her "former life".  Brain waves are changed when a dog is in a state of rest, even if she appears to be fully awake.  This may be a startle response to sudden approach.  If the dog snaps while fully attentive, on her feet, when someone reaches to pet her, you need a certified applied animal behaviorist ASAP because this dog has now passed the threshold of warning (growl).  If the dog snaps ONLY when at rest (whether fully asleep or just lying there with eyes open), we can perhaps attempt to counter condition the approach of humans and we will do that over the next TWO WEEKS in the following way:

At this time of year, Michael's or other sorts of stores that sell decorative things have jingle bells.  Every member of the household must keep jingle bells IN THEIR POCKET while at home.  Casually, over the course of every day events and while the dog is fully awake and behaving in a calm and friendly manner, JINGLE THE BELLS IN YOUR POCKET and, at the same moment, drop a HIGH VALUE FOOD REWARD in front of the dog (in plain sight, do NOT bend over her, simply casually drop it.)  String cheese cut into bits works well as it is easily kept in a baggy in your pocket and holds up well over the course of the day.  At the end of approximately three to four days, the dog SHOULD have acquired a VERY strong conditioned response to the jingle bells:  their sound means high value treat.  She might even be trying to solicit the jingle bells by offering various behaviors (like sitting or getting underfoot) since she will be problem solving why this is happening (what is SHE doing to earn it).  If you see this, IGNORE IT, no jingle bells.  But this is a GOOD step.  Next: jingle bells casually when walking past her as she is lying down fully awake, with head raised: drop treat.  Continue for a day or two (you might see the dog actually rush up to you and LIE DOWN in order to earn this - IGNORE this.)  You are now ready to use the jingle bells ONLY when you are FORCED to approach her when she is resting/sleeping.  You will jingle before getting within three feet of her (ten seconds, no more, before you pass her).  You will NOT drop a treat, you will wait for to get up, then you will ask for "sit", give treat.  Do this continuously and religiously for the next TWO WEEKS and let's see if we can counter condition this dog out of this fight/flight/startle response (if that's what it is).  

The reason you DO NOT FOOD REWARD immediately after passing her when she is lying down in a situation that has provoked a snap is: we have to know what she is THINKING in that moment and food reward reinforces fear.  She will know what a jingle bell means, she will get up, change her "mind", approach, "sit" on command, be rewarded.

Do not encourage "strangers" or visitors to approach this dog for any reason.  It's quite possible someone stepped on her (or deliberately kicked her) while you were not watching.  Have her free to approach others (strangers) in the home but always that person(s) must ask for "sit" before giving attention and never reach over the dog's head to pat her head or back.  We want to avoid any possible escalation of this if it is rank opportunism rather than a conditioned response.  I can't see anything from here.

Report back using followup feature so I can see original question/answer IN TWO WEEKS when our experiment has concluded.

---------- FOLLOW-UP ----------

QUESTION: Hello again,
To follow-up: we've been doing the bell scenario and it's worked as far as Nola understanding that the bell means treat if she sits nicely.  It has not however countered her snapping. Unfortunately, we're noticing that it's not just when she's laying down.  In a couple of instances since we last wrote you, she's singled out the same girl that I mentioned last time from across the room.  Nola has a very keen interest in her (which is weird because she's pretty uninterested in everything - toys, people, most bones, etc.), which as I mentioned is strange because the girl has been around since the day we brought Nola home.  The girl is pretty timid, which makes me wonder if Nola is having some sort of Alfa female issue? We know that the girl has certainly not harmed Nola.

We've also asked her doggy daycare team how she acts and they say that she jumps around a lot, plays with other dogs, has no signs of aggression at all. She's not at all rambunctious at home, but she loves the park where she pleasantly runs for 30 minutes straight with the other dogs. Could it be territorial?

We are contacting the rescue that we received her from to see if they have any advice, as well as a vet.  A friend of ours who works at rescues as a vet tech said that Nola may be depressed, so we're also looking into that.

We're terribly distraught and hope that we can resolve this issue soon.

Thanks so much for any further advice you might have and for your initial suggestion!

Nola is NOT "depressed", that's absurd.  Nola has an active dog to human aggression problem that needs immediate attention from a Certified Applied Animal Behaviorist (CAAB).  The jingle bells were intended to alert her of your BENIGN APPROACH and reward her obvious acceptance.  It's possible you are rewarding what she's THINKING or her fight/flight response rather than a change in attitude.  STOP.

Find a CAAB at one of the following sites:

"Alpha" is quite a misunderstood term and is not an appropriate designation of cause.  Such behavior is quite rare in the domestic dog and is breed specific.  Most dogs demonstrate aggression out of fear (conditioned response): 97% of the time.  Her "target" - the woman you speak of - has already "taught" her that her aggression works and so she may be persisting because of this.  I can't see anything from here.  You absolutely need immediate evaluation of this dog by an expert.

Canine Behavior

All Answers

Answers by Expert:

Ask Experts


Jill Connor, Ph.D.


I have spent my entire professional life rehabilitating the behavior of the domestic dog and I can answer any question regarding any behavior problem in any breed dog. I have answered more than 5,000 QUESTIONS on this site in the past (almost) eight years. If you are a caring, committed owner and need advice, I'm here for you. I am personally acquainted with my colleagues (Turid Rugaas, Ian Dunbar, etc.) who were members of an elite group in EGroups that I founded: K9Shrinks. THERE ARE NO QUICK FIXES for serious behavioral issues; not only is it unprofessional to offer same, it is also unethical. IF I ASK YOU SUBSEQUENT QUESTIONS, I NEED YOU TO INTERACT WITH ME. More information equals more credible answers and a more successful outcome. If you want ANSWERS THAT WORK, participate in any way I request. I'm quite committed to working on this site for YOUR benefit and the benefit of YOUR DOG. Help me in any way you can.


30 years of solving serious behavior problems in domestic dogs; expert in dog to human aggression; Internet columnist for for 5 years; former radio talk show host, WHPC.FM, Garden City, NY "Bite Back" (1995 through 2000). List owner, international animal behavior experts, Seminar leader: "Operant Conditioning and Learning"; "Aggression in The Domestic Dog"; "Solving Problem Behaviors" -- conducted for various training facilities on Long Island from 1993 through 2000. Former clinical director of "Behavioral Abnormalities" in conjunction with Mark Beckerman, DVM, Hempstead, New York.

Member, APDT (UK); Psychologists in Ethical Treatment with Animals

Harcourt Brace Learning Direct: "The Business of Dog Training" "The Fail Safe Dog: Brain Training, not Pain Training"

Ph.D., UC Berkeley

Past/Present Clients
Board of Directors: Northeast Dog Rescue Connection; The Dog Project; Sav-A-Dog Foundation; etc. Pro Bono counselor: Little Shelter Humane Society My practice is presently limited to forensics. I diagnose cause of dog bite, based upon testimony before the Court, for attorneys and insurance companies litigating dog bites, including fatal injuries. I also do pro bono work for bona fide rescue organizations, humane societies, et al, regarding such analysis in an effort to obtain release for dogs being held for death in municipal shelters in the US.

©2017 All rights reserved.