I guess I'll be the one to ask the question blackfire forgot to ask - can you eat horseshoe crabs and how do I catch them off my pier? (sorry for the spelling).
HorseShoe crabs are edible, but only about 1/3 of them. From the hinged point just behind the head area to about 2/3 the way down the tail. This area of the Horseshoe crab is know as the "ediblecrabiekustarea" no other are should be even attempted eaten.
The best bait for Horseshoe crab is IRON. This is where they have derived their name "Horseshooiekusscrabiecuss" translated to mean IRON CRAB or Crab of Iron. Old Timers used old rusty horse shoes for bait hence their common name, however today with the lack of horses for transportation most commercial horse shoe crab fisherman rely on rebar, rusty motor blocks, brake drums, h beams, I beams and so on.
Normally below the temps of 40 degrees the horse shoe crab is not active, however on sunny days even ice covered waters can produce horse shoe crab of monumental size and weight as scientists through out the world are begining to see the "HORSESHOOIEKUSSCRABIECUSS" responding to UV light. We are in the very early stages of this finding and will be bring to light more as time goes on.
For now yes it is possible under the right conditions to catch the "HORSESHOOIEKUSSCRABIECUSS" ( the common horse shoe crab) off your pier.
Thank You for your question and we will be looking forward to your next one as our Motto here is .....If we can not dazzle you with brilliance then WE WILL certainly baffle you with BS......................