How can you tell if it's play?

hi, we just brought home an eight-month old rescue, a small Toller,
about twenty five pounds. We're hoping she will be a companion to
another dog we rescued, a loving, easy-going, corgie-aussie mix, about
fifty pounds. The toller loves to nip at louis's ears and growls when
she is doing it.
She also pushes against him and mounts him. Louis tends to run away and
then stop and turn when she does it. His tail is up not in an
unfriendly manner, but nor is it wagging like the Toller's. I can't
tell if he's enjoying it or if he just wants to get away for real.
Twice, he's barked harshly at the Toller, when she tried to take his
morning milk bone and when she explored the inside of his crate, so he
is capable of saying no. He's also extremely attached to me. People say
we look like a tap dance team, that's how much he follows me
everywhere.

I guess I'm worried that he's so easy going, he'll be manhandled by the
little girl and I've made him miserable. This is a dog that waits by
our window for the neighbor to walk her dogs so he can play with them.
He loves other dogs (which is why we adopted another), but maybe only
when they go home.

I'd love to hear some thoughts on this.

Janet B...

The transition can be a little rough sometimes, especially bringing in
a young, active breed. Where did you do the initial intro?

To ease the adjustment, I believe dogs need to figure out
communication for themselves for the most part, unless there is
aggression involved. They each need to figure out how to communicate
limits to each other, but ultimately - YOU make the decisions.

I would be doing things with both of them that lessened the direct
interaction between them. Walks are a good example - they're together
but not in direct play. This is a great help in getting dogs used to
each other in a non-threatening way.

You can also tether or leash the new puppy a bit. If she isn't ready
to settle down in the evening, and he is, leashing her to you can help
teach her to settle down and leave him alone. I've had a few
instances where a puppy has needed this, and it doesn't take very
long. I currently have a 7.5 month old that has been here for a bit
over 2 months. He can be a pest and a playmate to my 5 and 9 year old
dogs, and I leashed him to settle him when one of the dogs had surgery
and was not up to his antics. Only one evening, but it was more
desirable to leash the pup than crate him, while letting my other dog
be able to choose his comfy spot to recover from his surgical day.