H.P. Lovecraft's "Innsmouth" and real-life Merbeings?

I myself have long wondered if Lovecraft could have based his sinister human-fishman hybrids in "The Shadow Over Innsmouth" on accounts he might have read of actual South Pacific folklore traditions of part-human part-fish "merbeings" somewhat resembling the "Mermaids" and "Mermen" of European legend?