With each passing day my older dog (5 year old staffy) is showing more and more bizarre behaviour that isn't normal for her.  I am not sure if it is serious or just that her nose is out of joint as she adjusts to life with a new pooch.

Like many staffy's she is quite intolerant of other dogs but has been great with the new pup.  She tolerates him and the worst she has done since day 1 is curl her lip at him when he has jumped on her and she can't get out the way (e.g. at the front door waiting for the door to open).

she has been great with him although they still get restricted access as he is too bouncy for her.  Anyway her behaviour has changed quite dramatically since the pup arrived and has been hyper alert when out for walks, always scanning the horizon with ears and hackles up.  She has been noising up other dogs and tonight she had a go at a another staffy who was in the same grassy bit as us.

She has also been running away from the dog walker and being a bit disobediant than usual.  I am just wondering how to tackle this.  Do I take her to dog training and go down a focussed obediance route, use the NILF method or just chill out and hope she gets used to the new living arrangements.

The pup has only been here 6 weeks so it is early days but I am interested in a few different perspectives on this.

It sounds to me as though your staff is being protective of the pup, looking out for other dogs that may harm the pup on walks, and not wanting to be away from him. This is good, but you need to let your dog know you are the protector and give her a nudge if she gets to edgy on walks.
I may be wrong, but if I am right it will settle as the pup gets bigger

Thanks Jacqui, she has been winding him up on walks which is driving me nuts!  In the snow she had on 2 seperate occassions something in her mouth (a ball on a rope one day and a bit of tree the next) and was going near him with it and putting it down but still standing over it.  When he came close she was giving him a look that generally means come any closer and you are getting told off - weird!  Is she just taunting him?

Sounds like she's teaching him manners and that she is in charge. Also sounds like she is being protective of him out on walks. Agree with other poster you need to gently remind her that you run the show and you will decide what is and isn't a threat, relieving her of that responsibility. But he's a baby and her instincts are coming to the fore.

Are you always walking them together? If so I would stop. Take the pup out for short walks on his own (he shouldn't be going for long walks anyway) and take her alone for her normal walks so she doesn't have to "protect" him. Hopefully she will then be a bit more relaxed.

What she is doing is natural ,but I worry that the pup will see her as the leader and not you. You need to teach the older dog to step back a bit. get out a toy and play with the pup but don't let the older dog join in, teach her that you want some space with the pup , and then ask her to join in when you are ready. If they get to ruff with a toy take it away and if the older dog is doing anything you are not happy with stop her. You need to let the pup see who calls the shots and that its you. If you don't, the pup will think the staff is the boss and this could mean having two naughty dogs later on. I did training in my house with my new pup and made the older dog sit and watch but not join in. he got a treat  for not interfering with my training with the pup. At the moment your staff is just being a good babysitter, but don't let her take charge of the pup.

ok, they get some walks together (e.g. first thing in the morning and often a short one in the evening but missy gets the long ones on her own and he gets out to the park at 'peak times' with a view to meeting lots of dogs for his socialisation.  Missy doesn't get on these as she is a grumpy mare.

They don't play together as missy generally doesn't play although she will lie in the living room on the sofa or her bed and watch him (on a long line) playing.  It is strange because although she will tolerate/ignore him in the house she seems to want to protect him outside.

I will definitely start making sure I am boss although have been really conscious that I don't want him to see her negative behaviour and learn that it is 'normal'.  thanks for the advice so far, any more tips welcome.