It took a team of over 300 scientists nearly two decades, but the first systematic analysis of the conservation status of chondrichthyans (sharks, rays and chimaeras) has been completed. The results, published today (open access) in a paper titled “Extinction risk and conservation of the world’s sharks and rays,” are chilling.
“Our unprecedented analysis shows that sharks and their relatives – which make up one of the earth’s oldest and most ecologically diverse groups of animals — are facing an alarmingly elevated risk of extinction,” said Dr. Nick Dulvy, IUCN SSG Co-Chair and Professor at Simon Fraser University in British Columbia.
As of the writing of this paper, the IUCN Shark Specialist Group recognized 1,041 species of chondrichthyans. However, a new species is described, on average, every two or three weeks! Out of these 1,041 species of chondrichthyans, approximately one in four are considered “Threatened” by IUCN Red List criteria; 113 species are Vulnerable, 43 are Endangered, and 25 species are Critically Endangered. 487 species are considered Data Deficient, but the IUCN Shark Specialist Group estimates that 68 of them are likely to be Threatened as well! Most alarmingly, only 23% of known chondrichthyan species are considered Least Concern, the lowest percentage out of any group of vertebrates on land or sea!
A hierarchy of IUCN Red List categories. Note that “Threatened” includes Vulnerable, Endangered, and Critically Endangered
One of the two main factors influencing Threatened status is the size of the animal. Larger bodied species are sensitive to overfishing because they typically have a life history with slow growth, late age at maturity, and relatively few offspring. Additionally, living in coastal habitats (in other words, close to humans) makes a species more likely to be Threatened.
If interested citizens want to get involved in conservation and management policy, it’s absolutely vital to use proper terminology. The policy world can be full of confusing jargon, but there are few ways to discredit yourself in the eyes of decision makers as quickly as using a critical term incorrectly. In fact, it isn’t uncommon for a decision maker’s response to a petition or public comment to consist entirely of correcting inaccurate terminology, if a response is issued at all. There are well over 100 acronyms and terms that I’ve seen regularly used, but in the interest of brevity, I’ve selected what I believe to be the 15 most important terms that I’ve seen people repeatedly use incorrectly.
For each term, I’ve provided a definition from a scientific paper or technical report whenever possible. I have also provided some additional explanation in my own words, and some assistance from familiar memes. Whenever possible, I’ve linked to blog posts, articles, or websites that provide even more information. Most of these terms are broadly applicable to fisheries management policy, but some are specific to shark fisheries. It is not my intention with this post to strongly advocate for or against any specific policy (I do plenty of that with other posts), but to make sure everyone is speaking the same language.
As 16th Conference of the Parties of the Convention of International Trade in Endangered Species (CITES COP16, pronounced sight-eze) comes to a close, I’d like to reflect on something that made this meeting unlike almost any other wildlife conservation and management meeting in history. Yes, history was made as delegates voted to list commercially exploited shark species for the first time, and history was made when manta rays became the first shark or ray species to be listed under CITES the first time they were proposed, and that’s all fantastic news. However, what I believe made CITES COP16 a game-changer for wildlife conservation and management was the large-scale inclusion of online outreach by both attendees and organizers. For the first time ever, interested members of the public from all over the world could follow along (and to some degree, participate) in real time.
Caribbean reef shark, Bimini. Photo credit: David Shiffman
2011 was a relatively good year for sharks and rays. Presented below, in no particular order, are ten important shark conservation stories from the past year.
1. Shark sanctuaries. The world gained several new shark sanctuaries, areas where shark fishing is banned, in 2011. Nations creating new shark sanctuaries include Honduras (~92,000 square miles), the Bahamas (~240,000 square miles), Marshall Islands/Guam/Palau (a regional partnership protecting almost 2 million square miles). Numerous concerns about enforcing rules in these huge areas, as well as concerns about potential loopholes in the policies, exist among conservation scientists.
2. Fin bans. These laws ban the possession, trade, or sale of shark fins within the boundaries of a city, state/territory, or country. In 2011, Hawaii’s first-in-the-US fin ban took effect, and a few other US states (California, Washington, and Oregon) passed similar laws. There is an ongoing debate in the shark conservation community about whether blanket bans on finning are better than promoting best practices (i.e. more sustainable shark fishing techniques). Additionally, some are concerned that we aren’t focusing enough on other threats to sharks like bycatch and habitat destruction.
Manta rays are true gentle giants; though they can grow more than 20 feet wide from wingtip to wingtip, they eat only plankton. Swimming with these animals is a rare thrill for SCUBA divers, and manta-viewing ecotourism is worth over $100 million each year. Like many species of sharks, manta rays grow slowly and reproduce rarely. According to Dr. Nick Dulvy of the IUCN Shark Specialist Group, ” they give birth to an average of one offspring every two years…they are a long-lived species with little capacity to cope with modern fishing methods.” They also migrate across huge distances, regularly crossing between national boundaries and spending much of their time on the high seas, making management difficult.
Photo credit: David Shiffman (Georgia Aquarium)
Although their biology cannot support a large-scale fishery and their behavior makes any fishery inherently difficult to manage, manta rays are very much in demand. At least part of them is: their gill rakers. According to Lucy Harrison, program officer for the IUCN Shark Specialist group, “Increasing demand for these fishes’ filter-feeding system for traditional Chinese medicinal purposes, especially in Hong Kong, is rapidly driving down their population everywhere.”
By some measures, the global population of manta rays has declined by more than 30% in recent decades, with some local populations facing much larger declines. Earlier this week, an IUCN Shark Specialist Group team led by Andrea Marshall has concluded that both species of manta ray (the giant manta Manta birostris and the reef manta Manta alfredi) should be declared Vulnerable* to extinction.
The IUCN Shark Specialist Group recommends that several steps be taken to protect mantas from further population declines. These include discussing the value of international conservation treaties, such as CMS and CITES, for both species as well as national-level policy changes in countries that fish for mantas. Some of these proposals may benefit from the support of the online conservation community, so please stay tuned! I’ll continue to report on these suggested policies as they moves forward.
* “Vulnerable” in the context of an IUCN Red List status should be capitalized, as should other IUCN Red List statuses. For more information on what “Vulnerable” means, please visit the Red List website here.