Unfortunately this time of the year most of the Fraser River action takes place further upstream where salmon have been spawning. Both trout and char (searun cutthroat trout, bull trout, dolly varden) and the odd predatory coarse fish (northern pikeminnow) are searching for food between New Westminster and Hope, so you would be more successful by fishing in tributaries in these areas. They feed on three items - dead salmon flesh and salmon eggs right now, juvenile salmon in march and April.
Even though the concentrated populations are further upstream, encountering trout and char in the area you mentioned is not impossible, because they do feed on small sculpins and other small fish which reside in the estuary portion of the Fraser River. That's as much assistance as I can offer since I do not fish the area much. Typically common carp fishing also starts in February, but the weather has been so cold it is most likely delayed. If not, those "streams"/canals in Ladner and Deas Island should produce.
Regarding crabbing, give it another month or two, you will find it more productive then. Good luck.