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Canine Behavior/Territorial


We have a 15 year old Rat Terrier. We love him like a family member,and love to play with him. However when anybody gets around him when he has his toy,or when he is eating,or if someone just touches a family member,he gets very aggressive. He will growl,bark and has even snapped at us. How do we resolve this problem.
He is also very territorial about our house. He don't like the Mailman, or Black people. If they come near the house he acts like he will tare them up. He barks and growl at them,and when they are gone he is agitated for some time afterwards

Your dog is FIFTEEN YEARS OLD.  UNLESS this has RECENTLY become a problem, I cannot help you in a text box.  IF THESE ARE PROBLEMS THAT HAVE JUST BEGUN, then first stop: veterinarian for full physiological scrutiny including basic neurological testing, orthopedic check and full blood chemistry (including thyroid). IF these problems are NEW, you MUST START with a very good veterinarian or veterinary behaviorist.  You might find a veterinary behaviorist from the following link OR by calling the Veterinary college in your geographical area.

IF these problems are long standing (for the majority of the dog's life), you will still require a veterinary behaviorist and your dog may require medication (to boost cognition or to truncate the flow of adrenaline).  At fifteen, he may have a few more years to live; if his cognition is failing (not uncommon in an elderly dog), his aggression (if not recent, but long standing) will worsen.  You must avoid all situations wherein the dog responds with aggression.  Since he is elderly, your best approach at this point is to prevent him from "resource guarding" (food and toys) by feeding him (twice daily, very important) in a room behind a closed door (leave food down for 15 minutes each time, do not pick up bowl in his sight whether or not he has eaten; he will not starve himself, he will make the adjustment); remove all toys.  If "someone" other than family is in your home, put a house leash on him (lightweight leash, handle cut off); should he respond with aggression (barking, lunging, snapping) should this "someone" touch a family member (to greet, hug, etc.), pick up the house tab, make no eye contact, say nothing to him, put him behind a closed door to the count of TWENTY, let him out: repeat every single time he reacts to a family member being lovingly touched by visitors.  You "love to play with him", very good.  NO TUG OF WAR GAMES.  Play with large, soft rubber ball (go to Toys R Us) and roll it around, let him chase it.  At end of game, pick up the ball and put it away.  Give him only one toy at a time and be sure to pick it up and put it away (it is YOURS, not his).  If he growls at you, do not back away, break eye contact, yawn and lick your lips (calming signals) and stand your ground until he STOPS.  Then ask for "sit", verbally reward, walk away.  Never confront aggression and never accede to it (in this case).

Let me repeat: first stop veterinarian; second, do as I suggested; third, use followup feature to report veterinary findings.  As for mailman aggression: quite common.  Dog barks frantically when mailman comes to the mailbox and mailman always goes away: dog then considers his behavior as having caused mailman to leave.  As for African American people: poorly socialized dog or dog has had a very terrifying encounter with an African American person (highly unlikely).  Can this be fixed?  Yes but at age fifteen you will see "response perseverance" mixed with failing cognition and it will be very, very difficult.

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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.

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