Young Puppy Will Not Stop Leading Another Puppy By The Neck
(Mountains NC, USA)
This is a new on on me. We have had Aussies since 1981. This is a long read but all information is below.
At this time we have 3 Aussies (full size) one is 12 years old named Willie Lee. We wanted to get another puppy while Willie was still around to show him the ropes. Enters Augustus Odell at 19 weeks old. Life is going good and working out OK for 2+ months until last week. We received a call from one of breeders we had talked to to say a couple needed to find a home for their female puppy that is 4 days older than "Gus". We took in the puppy and named her Beckie Lou. At this time "Gus is leading "Beckie" around by the scruff of her neck. Beckie is much smaller than Gus and he has a good 8-10 Lbs on her. I noticed our older dog did this with Gus in playing but never caused pain and was doing it in play. Gus will charge over to Beckie just to do it. Augustus and Beckie are from two separate breeders. I have at this time put a mesh muzzle on Gus when they go outside to take care of business. Last night it happened once during inside play time. We live in a forest environment which allows them to have free run.
This is not what I feel is a boredom issue as they exercise hard 1.5 hours a day. Swim 20 minutes every other day, and have over 30 toys to play with. We spend another 30 minutes a night throwing toys and playing inside. All this time working on behavior. At the dog park this does not happen only when we are at home. Beckie is not avoiding Gus at this point and we want to keep it that way.
My question is three part:
May I assume this is learned behavior from our older dog?
Second how can I stop this behavior short of a muzzle as his puppy teeth are still very sharp?
Let them work out by letting her let him know enough is enough?
We seek useful advice to solve this issue short of pulling his teeth.