Dr. David Shiffman is a marine conservation biologist and public science educator based in Washington, D.C. Renowned for his witty social media presence, he has written for the widely-read ocean science blog Southern Fried Science, and his science writing has appeared in publications including the Washington Post, Scientific American, Gizmodo and Scuba Diving Magazine. Follow along with him on Twitter, Facebook and Instagram, and stay tuned for his future contributions to the blog.
There hasn’t been a lot of good news about mako sharks lately in ocean science and conservation. Some of this news is presented in a technical manner that’s difficult to understand if you don’t have a background in fisheries biology or international conservation policy, so I’m here to help explain the current issues facing these sharks. First, let’s review the basics about makos.
There are two species of mako sharks, the shortfin mako Isurus oxyrhynchus (perhaps best known because they hold the record for being the fastest-swimming fish in the ocean, able to swim up to 46 miles per hour) and the longfin mako Isurus paucus. As you might expect, the main difference is that longfin makos have longer fins than shortfin makos … aren’t we scientists clever when naming species? Though both species are doing quite poorly in terms of conservation status, most of the focus lately has been on shortfin makos.
Both mako species are in the family Lamnidae, which also includes the great white shark, the salmon shark and the porbeagle shark. Sharks in this family are relatively large with what you’d expect from a typical shark body type and are found swimming in the water column rather than resting on the seafloor. Though salmon sharks and porbeagles are found in cold water, makos and great whites can also be found in tropical waters. Makos are usually located relatively far from shore and are commonly seen in the open ocean. They usually eat squid and large fishes, like tunas and swordfish.
Why are makos in trouble?
Remember when I said that mako sharks commonly eat tunas and swordfish? Well, mako sharks can end up as bycatch, or unintentionally-caught species, especially in tuna and swordfish fisheries. With this, because both the fins and meat from mako sharks are valuable, there’s been relatively little incentive for fishermen to reduce this bycatch or release the makos they catch (yes, this meat ends up being sold, and the shark fin trade is neither the largest nor the only threat to sharks; the general meat trade is also a significant and increasing threat to sharks overall). The species is also a popular sportfish among recreational anglers.
These issues pose enough of a threat that over the last 75 years, shortfin mako sharks have declined in population worldwide by 50-79%, which is enough to be listed as Endangered according to the standard of the IUCN Red List, an international group of scientific experts. This alarming news about shortfins was announced in 2019, alongside an announcement that longfin makos are also now listed as Endangered.
NOAA Fisheries (the U.S. government agency that manages fishing) also considers shortfin makos in the Atlantic “overfished, with overfishing occurring.” This means that the species has been reduced to the point where their populations are too low, and the rate of fishing is still too high to be sustainable.
What’s new in the world of mako shark conservation?
Though incremental, 2019 did show some improvement for mako shark conservation. First, both species of mako sharks were proposed for what’s called an Appendix II listing at CITES, the Convention on International Trade in Endangered Species of Wild Flora and Fauna (a United Nations-associated international agreement). An Appendix II listing doesn’t ban international trade, but it does restrict and monitor it closely. Countries aren’t allowed to trade products from Appendix II listed species unless certain conditions are met, and they have to keep very careful records. This was considered an important first step in making international mako conservation and management more sustainable.
Next, there was a proposal to protect makos at ICCAT, the International Commission for the Conservation of Atlantic Tunas. ICCAT is a Regional Fisheries Management Organization which brings together representatives from all the fishing nations that fish for the same stock (or population) of fish. This is designed to promote international cooperation and mutually agreed-upon rules. The proposed mako shark protections at ICCAT were intended to complement their CITES Appendix II listing, but they, unfortunately, ended up failing to pass. This was a setback, and it’s worth noting that the United States played a role in that setback.
What does this all mean?
Mako sharks are fascinating and ecologically important animals. There’s increasing recognition that mako sharks are in serious need of conservation action, but the science-backed protections they need are meeting a significant amount of resistance from unexpected sources from world governments including the United States, long considered a world leader in shark fisheries management. What’s next for these animals and their conservation remains to be seen.
While the future of these magnificent creatures is uncertain, there are still ways to stay up-to-date on the best ways to help support their protection and conservation. Be sure to sign up to receive email updates from Ocean Conservancy to be the first to learn about new ways to help support and protect species like mako sharks, and don’t forget to follow along with me on Twitter, Facebook and Instagram for updates on shark conservation and research news.