Originally posted by NZ_Ross The second one is a bit further south (still on your way to Wanaka and Queenstown) just out of Fox Glacier and allows you to see White Heron and Royal Spoonbill - I think it is pretty much the only place in NZ where you can expect to reliably see them.
Keep an eye out around the Wellington area for Spoonbills too. I've seen them sitting in the Pauatahanui inlet many times, often right by SH58! My parents also tell me they're not uncommon at the Waikanae river mouth and also various other rivers up that way.
Actually, that's one more birding spot. It's quite hit and miss depending on tides and other factors, but it's easily accessible.
Motukaraka Point is only 5 minutes off SH1 from Plimmerton. I often stop off there in summer when I have time and the camera. Many birds will be distant on the mudflats, but a good pair of binoculars can make for some great spotting and sometimes you get lucky with stuff closer in.
If you carry on along Grey's Road toward Pauatahanui you pass by some mudflats right by the road where you'll often see Pied Stilts and other waders. You can stop at the side of the road and get quite close if you're good at stalking. There are also walkways and hides in the wetlands which are accessed from within the Pauatahanui village. I saw my first Shoveler in there.
Edit: Here's a Pied Stilt I stalked.