Grady Problems

Oh Annie, I'm sorry to hear that. I can't help you much maybe pm Anne or Mic.

Boy,  I don't have any ideas either.  Some of mine also "resource guard" me and when that happens they lose the spot that they consider prime real estate......but gosh, with this going on in other places, I'm just not sure what to advise.  I second emailing Anne or Mic.

Thanks for your replies, ladies.  When it's happened in the past, we've put him in a deep time out.  In another room where there are no other dogs.  He's in there for 20 minutes.  We wait until he's quiet & then let him out & don't even interact with him for another 10 minutes.  He's quite contrite, not submissive but he realizes that he's been punished.  I wasn't able to do that this time.
I'm wondering if he feels that he need to protect me.  In other words, I'm not a strong enough leader for him.  I don't know.
I'll PM both Anne & Mic for advice.
Thanks ladies.

You might want to check out the t.v. show that comes on Friday nights on Nat'l Geo channel, called The Dog Whisperer.   His name is Cesar Millan and he's excellent.   Many of the worlds best dog behaviorist consider Cesar to be the at the top of the list of great behaviorist.   You can also order his CD.   Good luck.

Bill 

Bill, as you probably know, not many of us consider CM to be "all of that".

Oh, Grady boy. That's no good at all. I hope you get him figured out, Annie. 

Grady, you've gotta behave yourself Mister. I don't know what to say. Millie goes after Max sometimes if he's getting what she feels is too much attention, but it sounds like Grady does more than what she does. She usually just runs him off or air snaps him, she doesn't usually make contact. For a while though, when Max came to me, if Millie was in the way of the shortest path, Max would take the longest way around to avoid crossing her path. 

Thanks guys (generic for both sexes ))  I appreciate the responses.

Annie, I think it would be wise to consult with a legitimate behaviorist.  You can try getting a recommendation from your vet.
How old is Grady?  Neutered? Breed(s)? 
Some dogs just don't like day care environments, and will take matters into their own hands if they think the leader isn't protecting them (and perhaps not just from other dogs - there are other scary things in dogs' lives).  Some dogs do resource guard their owners, or space around themselves.  Dogs of certain breeds become more aggressive to other dogs when they reach adulthood.  Whatever is causing this, it isn't fair to clients' dogs to put them in danger.  And, it isn't fair to Grady to have this escalate to the point where he comes to the attention of animal control or attorneys.  He may, sadly, be one of those dogs that needs to be left at home.  I would say get professional help from someone who is willing to observe him firsthand.

Anne, Grady is a mix.  I think he's a lab/hound cross. or a mutt form many generations of mutts.  I don't know & I can only guesstimate his age.  I'd say he's 2.5-3 years old.  He's a rescue that joined my family a year ago December.
From observation, this is what I can see.  It's mostly un-altered males he starts with.  He has no problem with speutered dogs.  He's great 99.9% of the time.  He LOVES to play with everyone & plays well with the other dogs.  It's just when I go into the yard with the dogs & pay extra attention to a dog other than Grady.  I know it's not fair to the other dogs, their owners & Grady & I certainly do not want to put anyone @ risk.  It also seems to happen  when snacks are given.  He is fine @ home with Aspen & resources, more or less.  When I'm loving Aspen, he always seems to get in between us as if to say, you must love me first.  I always greet him first when coming home, let him out first (make Aspen wait at the door so Grady can go out first) let Grady back in first, feed him first.  I guess I'm still thinking it's something I've been doing wrong & it's not his fault.  I will call my vet who knows him & also specializes in behavior issues.  Do you think a good dose of NILIF might help him?  Or should I delve into clicker training or something to show him that I do not need to be protected.

Clicker training is never a waste of time, no matter what your objectives are, because it teaches clear communication between you and your dog.
Most people know that I object to unsupervised dog parks.  At my play group, treats, soft toys or squeak toys are not allowed.  They cause fights.  In fact, if we have a "guardy" dog in the group, we refrain from using even tennis balls or rope tugs.  Also, if there isn't anyone on the premises who is experienced with dog behavior, a dog may get labeled as aggressive, when in fact he is frightened.  Or, a simple case of resource guarding escalates into a fight because the idiots there refuse to see that their dog's favorite "binky" is causing the mess and they refuse to put it away. 
In any case, the dog park is not the place to work out problem behaviors - it's for dogs who get along with others.  (The occasional grr to keep a rude dog out of one's face is fine, so long as it isn't followed by puncture wounds LOL)
Without seeing Grady's behavior firsthand, I really can't comment.  But, I do think it might help to hire a local trainer to accompany you to the park and see what's really going on with him. 
If it's just unneutered dogs, that may have something to do with their approach or body language.  Dunno.  Get someone to view this.