In Marcus Rediker's article about sharks and the slave trade, while some sharks may have followed the slave ships across the Atlantic, he does not indicate that it caused the grounds of where particular types of sharks lived to permanently change. The sharks would be attracted to the ships for sure, but there are different types of sharks that live on the African coast and on in the deep sea regions of the Atlantic. When the slave ships were on the coast of Africa, sharks that lived in those waters would reside closer to ships that are throwing dead slaves into the water - and in the deep sea between Africa and the Americas other types of sharks would pick up.

If you want more detail than that, you'll want to pick up the article - Rediker, Marcus. “History from below the Water Line: Sharks and the Atlantic Slave Trade.” Atlantic Studies 5, no. 2 (August 2008): 285–297.