when the boat captain calls to his crew
"Cast the hook" he means drop the anchor.
this photo shows how to cast the hook without any captain, crew or anybody actually dropping the anchor. all that is required is the sun at the right angle.
everybody guessed it was a hook, just not the anchor type.
however 
"Throwing my guess that the objects creating the shadow have to do with holding something up - a hook and chain on a planter or perhaps for a boat."
throwing, holding, hook, chain, boat... not exactly enough reason to go parading the streets in the middle of the winter but close enough for 1 HBD.
also 1 HBD to 
"Right answer: an umbrella
Fanny answer: the band of captain hook: you can Also see the Puff sleeve around the wrist"
i hope you noticed the reflection of the 'hook' in the photo above. if you like reflections there is still time to join the
reflection hunters contest 47 here:
@olgavita/reflection-hunters-contest-round-47
and don't miss the classic shadow hunters contest:
@melinda010100/show-me-a-shadow-smash
of course i will post another guess the shadow very soon
hope to see you there