The species' problem is its habitat. Oceanic whitetips live in the same open-ocean surface layer that pelagic longlines target for tuna and swordfish, and their habit of investigating anything in the water makes them highly catchable. They are taken as bycatch on an enormous scale, and their large fins are among the most valued in the fin trade.
The declines are steep wherever there is a time series. Gulf of Mexico and central Pacific analyses have found reductions of the order of ninety percent or more over decades, though the earliest baselines are estimates from fishery records rather than surveys.
The species is now listed on CITES Appendix II, protected under several regional fishery bodies, and listed as Threatened under the US Endangered Species Act. Recovery is limited by biology: litters are around one to fourteen pups, gestation runs about a year, and maturity takes years, so removal outpaces replacement even where retention is banned.