The vertical black bar disappears as the fish gets older and other black lines become more prominent. Along with other Caribbean Seas reef dwelling tropical fish, many young spotfin butterfly fish get sucked up the gulf stream from July to late October and are dumped into Long Island bays.
As the fish ages, the vertical black bar fades away while other black lines become more noticeable. Alongside other tropical reef-dwelling Caribbean Sea species, many young spotted butterfly fish are drawn into the Gulf Stream from July to late October and then released into Long Island bays.