Which CO2 or multi pump?

Green shade cloth if you have any. It has to be dark inside so you don't silhouette. I had a lot success with that with just propped up against the fence like a pile. I'd get into it with a single layer where I could see through it, double everywhere else and done in such a way I could push the barrel through where the single and double layers met.one place in it I had a hole in the mesh and put a flap over it.
It they are close you can leave the scope behind the mesh where barrel is poking out. Further away in the branches gets bit to difficult to distinguish them. Scope will be your biggest give away in the end. So less they see it the better. Its why I have camo cloth over mine. But at the end of the day that big lens looking strait at them is pretty noticeable.
However for some reason they have hard time seeing through the shade cloth. Mind you I'd usually have a camo shirt, hat, and fingerless gloves on. But they never picked up on the scope when it was behind the mesh. They occasionally did when I was pushing the scope past the netting.

Good advice Kruz, I've been ready your posts about shooting the starlings and mynas and how challenging it could be.  I used to have similar challenges shooting jackdaws back home. They nested down the chimney and took nestling birds etc. I could walk around the garden all day and they'd sit on top of the chimneys, no sign of them flying off but the first sign of me holding an air rifle and they were off. It got to the point that as soon as they saw me going into the house they'd fly off. In the end I had best results shooting them from a bedroom window, curtains drawn as they fed on the bird feeders.

Preset your shooting spots around the barn and get cover in place way before you start shooting. Let them get use to it.
I shot way more starlings here than I ever got on the farm, simply because on the farm I just started shooting in plan sight. They picked up pretty quick what a gun was. Here it's taken them a while mostly because I've always shot from the bathroom.(I have both windows covered off and a drop sheet down one side of window because they set sentries on a tree that could look in from above on that side which I had to stick me head out the window to see. When nesting season comes if you lay off them let them nest and lay, you'll get better results as they have to come back to chick's.
On farm I started in nesting season by fluke, as soon as nesting season was over they split to other trees on the farm. Set up a couple of hides or cover on the opposite side of where your shooting for later on when they get onto you. They will get smart and start coming in from behind cover thats blocking your view. They can get into and out of thier crevice nest at a surprising rate. Way faster than you could aim and shoot.

Thanks Kruz and I agree with the sentiment. There's not a heap of active members on here but I really like the communtiy spirit. 

FPM, appreciate the recommendation but I am in the process of buying a break barrel from Paul, just waiting on the mail order form to be processed now.  That's half the problem, if I had that in my hands I'd be spending more time out shooting that and less time thinking about other guns I'd like to buy.  What appeals to me about the CO2 and pump guns is that they should shoot a bit more like a pcp and I would think be quieter than most springers, once surpressed. I don't need a lot of power for starlings around the barn so CO2 shouldn't be an issue. I'll have the break barrel for extra power when I need it.

I'm an airgun shooter. Not a sales person. I had mercs offer the same with a steel breach when I got the 362. I really appreciated that.
Should be a community of shooters on here. I'm happy to help where I can.
Won't kill me Im not getting to far with my big Feb plans anyway. Bloody rain.