There's no doubt that Appendix II trade has helped protect many species of sharks and rays, as well as countless other beloved species of wildlife. While unsustainable overfishing is the greatest threat to sharks and rays, sustainable fisheries for these animals exist - though these primarily can be found in wealthy countries with well-resourced fisheries management regimes - and are a popular policy solution among scientists and conservationists. But for other species, and for countries without well-resourced fisheries management, populations have declined so dramatically, and illegal fishing is so rampant, that a total ban on all international trade, like a CITES Appendix I listing, is the only path forward. "For some shark and ray species such as the oceanic whitetip or manta rays, sustainable fisheries aren't the answer - full protections at a national and regional level coupled to CITES Appendix I trade bans are the only means left to prevent their imminent extinction," Warwick from WCS told me. "We've seen this work for other species, like green sea turtles, which have been brought back from the brink. Why shouldn't the world's most threatened sharks and rays be offered the same lifeline?" CITES Appendix II protections have been a lifeline for many threatened species of sharks and rays. But for especially endangered species like oceanic whitetip sharks and rhino rays, we need to go further. Appendix II isn't enough. Proposals at the upcoming CITES COP20 include transferring oceanic whitetip sharks from Appendix II to Appendix I, and providing similar protections for rhino rays. Governments meeting at COP20 in Uzbekistan should follow the science, support these proposals, and help save these sharks and rays from the brink of extinction. It's the only way to give these species a fighting chance at survival.