In May 2011 a well respected UK bass guide told me, "It's not worth fly fishing for bass in the early spring as all the big fish are targeting the shore crabs coming our of the harbours to release their eggs".



Have you targeted bass with crab flies near harbours in the early spring or know of other doing so?

First off I wouldn't listen to your bass guide too much. If fish are around then they WILL eat flies if you can get one in front of them. I think the challenge is how do you fish the crab fly? Bass typically use smell to find crabs. I guess a dead drifted crab fly would work if you could drift it past a bass.
In the Cape they catch on crab flies by sight casting to mouching fish.

I've tied some up exactly for this but will see how standard patterns fare first:

I think it was Mike Collins who used to use crabs effectively. He tied the shell out of a wine cork cut into a sliver and added silly legs and feathers for the claws, with someepoxy or softex on the feathers to give them the stiffness.

He had pictures of the shadow that these flies cast (weighted at the eye end so they sat on the bottom and waved in the tide with the buoyancy of the cork lifting the non weighted end of the hook - the business end. Anyway, the shadow these flies cast was amazing. I am sorry he doesn't post anywhere anymore - he got browned off with people questioning him and saying he was making stuff up, yet he was a really good fly rodder.