Shelter Island...slow

Does anyone know what is out in front of the middle and right side of the pier that you get snagged on. I've heard it's rip rap covering some type of utility. I know they put reef building obstacles in some other parts of the bay but haven't seen anything about this area. Also searched for documentation about utilities being laid down here. I get snagged out front on the left side and can feel my line moving as if it's caught on a cable, so maybe it's not covered in that section. Someone could dive out there and recover a whole lot of tackle
I thought about it since not much else was working. I know some have caught big sheepshead at this pier.

Not really sure if their is a size limit for this type of crab. Looks like a blue crab with those rear swimming legs.
This crab is a Xantus Swimmer Crab (Portunus xantusii). It has no size limit and a bag limit of 35. I have seen people attempt to use this crab as bait at the Huntington Beach Pier on heavy setups meant for sharks or rays, but with no success. I think these crabs are too big for surfperch, Opaleye, or croaker, but don't have enough meat for sharks or rays. I do think they would make excellent bait for Sheephead or other bigger game fish if used in the right environment.