Dog nipping puppy

Question
We have a 5 year old female German Shepherd (Hazel) and we just got a female German Shepherd puppy (8 weeks old).  When the two are together (under close supervision), Hazel is constantly giving her little bites like she is trying to remove bugs from her.  She also, what looks like, tries to pick her up by her neck.  I'm guessing it's a mother instinct.  Hazel was spayed shortly after she was a pup (4 years ago).  Am I right about the "mothering" thing?  Thank you for your time.

Answer
While many 5 year old females want nothing to do with puppies, it sounds like your Hazel is mothering it.  In a wolf pack, it is the responsibility for all the adults to care for the puppies.  Some dogs step right up and do it, and others want nothing to do with the puppies.