I went to Curacao in 2014 for a week for Mardi Gras/ Karnaval from previous Wednesday--Ash Wednesday. I spent the first 2 nights money-paid at the Marriott resort which is now closed for remodeling, then 5 nights at the Renaissance DT Willemstad to be in walking distance of the thick of the Karnaval action. I swam at the first of these without hearing warnings of sharks.
However, way back in 2000 or 01 I went to Aruba, where I took a bus tour to the far side of the island. I remember the guide pointing out the prison & the garbage-treatment plant. He explained that they discharged the remains there to attract the sharks to there to deter prison escapes by sea & to keep the sharks away from the resort beaches!