I’m a resident of this area (Delta) and have hunted here for birds for almost 20 years. I have taken my share of ducks and geese but have since given it up. In Ladner, some of the best shooting is in the fields for which you will need to obtain permission from the farmers. I don’t know if that is difficult these days or not but you will have to try. Lots of greenhouses going up which is limiting areas to go.
There is also a private shooting club, for the life of me I can’t recall the name but they have posted their signs on many of the fields on the mainland, may want to look them up. Westham Isl is permit hunting only. The best shooting is rainy and windy days in a spud field or other that provides feed with lots of water. You can usually expect to see birds in the irrigation ditches that normally border these fields, jump shots are lots of fun, the mallards usually hold a bit longer than the rest.
My experience was best from about the last 1-2hrs of shooting time for birds coming in to feed. Failing that, Brunswick Beach is pretty good or has been in the past. Follow River Road past Westham Island, (Reifel Bird Sanctuary), until you reach the end of the road. Park and suit up (you need waders). Its ok to carry your gun unloaded along the dyke. You get lots of looks from non hunters but who cares, this was a hunting/fishing community long before the non hunters.
I can remember in early 80′s, opening day here was like a firing line. There were vehicles lined up for over 1km down the road, You couldn’t walk into the marsh very far because hunters were everywhere, people used to camp out over night to get a good spot and every bird that went by was shot at. Not anymore, you are lucky to run into another hunter there. This place has provided me many days of excellent shooting, a dog is a must to ensure you recover your birds. Careful of the ditches you cross as they are usually a lot deeper than they appear (trust me). If you walk out to the middle point on the dyke and head out from there you should be able to find a trail that leads out. You really want to go to the middle of the point in front of the large canal (lower tide) waters edge on high tide. Last time I was out there was a couple of permanent blinds still standing that had been there for many years.