A new study* has estimated that the total number of sharks killed by fisheries each year is between 63 and 273 million, with a average of approximately 100 million.In an interview, lead author Dr. Boris Worm explains the importance of this estimate:
“This is by far the most comprehensive estimate of shark mortality yet,” he said, ”because we consider all sources of mortality, from direct fishing, finning, and discard mortality. the estimate was derived by crunching numbers from almost 100 publications on the catches and mortality of sharks.”
Of all the numbers this team crunched, the most important thing to consider is whether the exploitation rate is greater than the rebound rate. In other words, is this level of exploitation more than the populations can recover from? Though many estimates and approximations went into calculating these figures, it seems quite clear that sharks are being harvested at an unsustainable rate.
Continue reading Breaking News! “Most Comprehensive Estimate of Mortality”: Between 63 and 273 Million Sharks Killed Each Year
Endangered species seem to be coming up around here more often than usual, mostly due to the potential state-level listing of great white sharks in California. This move has been resisted from some surprising corners, including researchers who are generally pro-shark conservation. The reasons why scientists might want to oppose an Endangered Species listing are laid out by Dr. Chris Lowe in an earlier post on this very blog, so I won’t reiterate all of them here. Surprisingly, I have yet to see any comments accusing Dr. Lowe of being a shill for the drift gillnet fishery.
There seems to a be a real sense among some conservation-minded folks that Endangered Species listing is something of a “holy grail” for species protection and recovery, and some petitioners would have you believe that anything less is unacceptable (and probably the result of corruption). However, the Endangered Species Act has a very specific process by which species receive protection, and a defined set of limitations. A lot of well-meaning people seem to have limited knowledge of this process and limitations. To do my little part to help fix this, this post will be a short primer on the Act and will show how a marine species has recently navigated the entire process for listing. With any luck, maybe this will result in one or two fewer misguided online petitions.
Continue reading The Endangered Species Act and Marine Animals: To List or Not To List?
Sites like Care2 and Causes, for better or for worse, make it easier than ever to write petitions
Online petitions have become a popular tool of the conservation movement. A well-written petition can be an important tool for helping to shape policy, particularly when used as part of a larger and well-organized lobbying and advocacy campaign. Many petitions, however, are so badly written as to be ineffective or even counterproductive when it comes to influencing real policy change. Even worse, they falsely perpetuate the idea that an activist has “done something” about the problem, which may prevent them from participating in a process that could result in real change.
In case you want to join the numerous activists who are filling my Facebook news feed and e-mail inbox with useless petitions, here is an easy 5 step guide for you to to follow, using examples from some real petitions I’ve been asked to sign.
A note on terminology: Petitions typically contain a few basic elements, which I term here “the problem”, “the target”, and “the solution”. The problem briefly describes the undesirable situation that the petition hopes to remedy. The target is who the petition is directed at. The solution is what should be done about the problem.
Continue reading How to make a completely useless online environmental petition in 5 easy steps
Dr. Chris Lowe is a Professor of Marine Biology at California State University Long Beach, and is Director of the CSULB Shark Lab. He has studied California’s great white sharks for more than 10 years, and has written more than 75 peer-reviewed scientific publications. Dr. Lowe also serves on the Board of Directors for the American Elasmobranch Society, the world’s largest professional organization of shark scientists. The following guest post was also submitted as a public comment to the California Department of Fish and Wildlife.
Comments for consideration on the petition to list white shark as threatened or endangered species:
I am a Professor of Marine Biology and the Director of the CSULB Shark Lab at California State University Long Beach and have been conducting State and Federally permitted white shark research in California since 2002. In addition, as a professional and published shark scientist who has studied a variety of shark species around the world, including white sharks in California, I would like to take this opportunity to express my personal professional opinion in regards to the petition request and the science behind it.
Continue reading Guest post: Why a California great white shark scientist opposes CA Endangered Species Act protections
Hi everyone. I’m Chuck and I used to blog primarily over at Ya Like Dags?, where my main focus was on interactions between apex predators (sharks mostly, but I also occasionally dabbled in other large fish and sea mammals) and those other top marine predators, humans. This was not in the “shark attack” sense, but in the context of fisheries management. Writing about this subject and living it as part of my research have given me valuable perspective on marine science and conservation that I really didn’t have as a freshly-minted Bachelor of Science.
Unfortunately I see more extreme versions of my old perspective show up in countless blog comments, posts, and tweets by perfectly well-meaning people whose only issue is that they’ve fallen for a simplistic, “us vs. them” attitude towards conservation. Consumptive uses of the ocean, such as fishing, are inherently evil and must be opposed. This no-compromise approach sounds cool and may bring in the TV ratings, but is it truly helpful?
Continue reading Inaugural Post: Fishermen Are Not Evil
The least-impacted places in the ocean are mainly in the deep sea, but as fishing technology has improved, even seamounts, sponge gardens and deep-sea coral beds are no longer out of reach of our appetites for seafood. Bottom trawling, which involves dragging a heavy weighted net along the seabed, is so destructive to benthic habitats that it has been compared to clear-cutting a forest. Bottom gillnetting catches almost anything that swims into them (and isn’t smaller than the mesh size), resulting in enormous levels of bycatch.
A (simplified) schematic of a bottom trawl. This one (on the NOAA vessel Henry Bigelow) is used for scientific sampling, not fishing, but it’s the same principle on a smaller scale. Image via Wikimedia Commons
The deep-sea fishing fleet of the European Union is one of the largest in the world, which is why it was so heartening to see the European Commission call for a phase-out of trawls and bottom gillnets recently. The Marine Conservation Institute, a longtime leader in marine protected areas, has obtained over 100 signatures (including mine) from marine scientists supporting a phase-out of bottom trawls and bottom gillnets by the EU fishing fleet. If you are a scientist who supports this measure, please consider adding your signature. This can be done by e-mailing [email protected] and including your name, institutional affiliation, degree, title, and full mailing address. Please note that MCI is primarily interested in signatures from the scientific community, and that simply posting a comment on this blog post is not equivalent to signing the petition.However, feel free to post a comment letting us know that you contacted MCI!
The full text of the petition can be seen after the jump:
Continue reading More than 100 marine scientists call for protecting the deep sea from trawling. Will you join us?
While the rest of the scientific and management community and I are grateful for the passionate support of many shark conservation advocates, passion is no substitute for knowledge and accuracy. Some conservation issues are a matter of opinion and can (and should) be reasonably be discussed by people with different views, but many others are a matter of fact. Presented here, in no particular order, are 13 incorrect statements and arguments commonly made by well-intentioned but uninformed shark conservation advocates, along with the reality of the situation.
1) “Shark finning” is synonymous and interchangeable with “the global shark fin trade.” Shark finning is a specific fishing method. It is not the only way to catch sharks, and it is not the only way to provide shark fins for the global fin trade. Stopping shark finning is a worthy goal (that has largely been accomplished already *) because it is a wasteful and brutal fishing method that complicates management, but stopping shark finning does not stop the global shark fin trade. Many people calling for a ban on finning really seem to want no shark fishing and no fin trade of any kind (a viewpoint I disagree with, but regardless, proper terminology matters). For more on the difference between shark fishing and shark finning, see this post from June 2012.
2) 100 million sharks a year are killed for their fins. The origin of this number is still debated, but it was popularized by Sharkwater. While we will likely never know exactly how many sharks are “killed for their fins”, the best scientific estimate of the scope of the fin trade we have comes from a 2006 paper by Dr. Shelley Clarke. She found that the fins of between 26 and 73 million sharks end up in the fin trade each year, with a simulation average of 38 million. Dr. Clarke wrote an essay for SeaWeb on the misuse of her work, which is worth a read.
3) 1 in 3 species of sharks face extinction. This one is actually relatively close to accurate, and can be fixed with the addition of just two words. An IUCN Shark Specialist Group report found that 1 in 3 species of “open ocean” sharks are Threatened with extinction (Threatened means Vulnerable, Endangered or Critically Endangered according to IUCN Red List standards). 1 in 6 species of shark, skate, ray, or chimera are Threatened- while still a troubling number indicative of a very bad situation, it’s half as bad as claimed by many advocates. Also, please note that I included skates and rays, which are similarly threatened but often ignored by conservation advocates (with one notable exception from 2012).
Continue reading 13 wrong things about sharks that conservation advocates should stop saying in 2013 (and what they should say instead)
A menhaden, image courtesy Pew Environment Group
Despite their small size and plain appearance, menhaden have been called “the most important fish in the sea” because numerous coastal fish species rely on them for food. Although they aren’t typically eaten by humans, there is still a huge fishery for them for bait, aquaculture food, and oil. That fishery has been essentially unregulated, allowing fishermen to take as many as they want. Recently, there’s been a campaign among certain environmental groups to fix this problem and put catch limits in place for menhaden.
I was surprised to see PolitiFact, a non-partisan political fact-checking website, address this issue. I’ve checked PolitiFact pretty regularly for years, and I’ve never seen them cover a topic like this before. They focused on a claim by the Pew Environment Group that “In recent years, menhaden numbers along our coast have plummeted by 90 percent.” While I admit I am not familiar with specific details of menhaden population trends, anyone who has paid any attention at all to the ocean knows that we’re overfishing at alarming rates. According to the UN Food and Agriculture Organization, approximately 1/3 of all global fisheries are depleted or overexploited, many by more than the 90% referenced for menhaden. Shockingly, PolitiFact called the claim by Pew “mostly false”. Their reasoning for this ruling is even more ridiculous than the ruling itself:
Continue reading PolitiFact calls claims of menhaden declines “Mostly False”, is completely wrong
I am, among other things, a conservation geneticist. What that means is that I use the tools of molecular ecology and population genetics to make observations about species and populations in at-risk ecosystems, assess the status of anthropogenically disturbed populations, and generate data that has direct applications to conservation and management issues. Essentially, the only difference between what I do and what a population geneticist or molecular ecologist does is the motivation—I select systems to work in that have a high conservation priority.
This motivation leads to a constant intellectual conflict at the bench. The tools of molecular ecology—PCR, gene sequencing, and, more frequently, high-throughput sequencing—are waste intensive. In order to avoid cross-contamination and practice precise, clean, technique, we use thousands of tiny plastic consumables every day. These come in the form of pipette tips, sterile packaging material, micro-centrifuge tubes, and numerous other plastic widgets. Often, because of the biohazard potential, these consumable cannot be recycled.
So we have a problem. As a conservation geneticist, we need these tools to produce the data necessary to make wise conservation and management decisions. As a sustainability minded individual, I find the massive daily accumulation of plastic waste inexcusable. Do we just accept this waste as the cost of conservation genetics? I believe that the answer is no. I think we can and should develop best practices to minimize the amount of plastic waste produced by a molecular lab while maintaining good, sterile technique. I would like to propose four guidelines, based off the principles of Reduce, Reuse, and Recycle, for minimizing waste in a conservation genetics lab.
Continue reading Establishing Best Practices to Minimize Waste in a Conservation Genetics Lab
A newly-released list of proposed amendments for the upcoming CITES Conference of the Parties includes proposals to protect ten species of sharks and rays, a record-breaking number. These include three species of hammerheads, oceanic whitetip sharks, porbeagle sharks, three species of freshwater stingray, and both species of manta ray.
In total, 37 countries are involved in the proposed amendments. As expected, the United States is a co-sponsor of the oceanic whitetip measure. Additional noteworthy participants include major shark fishing nations like Mexico (co-sponsoring the hammerhead proposal) and the European Union (co-sponsoring the hammerhead and leading the porbeagle proposals).
“International trade is a major driver for shark fisheries around the world, and yet controls on this exploitation are woefully insufficient,” said Sonja Fordham, President of Shark Advocates International. “We are grateful for continued U.S. leadership in addressing international shark trade, and welcome this unprecedented number of proposals to safeguard these vulnerable species under CITES.”
Threats to these animals are diverse and include directed catch for both fins and meat, bycatch, alternative medicine (gill rakers), and even the aquarium trade. Each of the freshwater stingray species are considered Data Deficient by the IUCN Red List, scalloped and great hammerheads are considered Endangered, and the other species are Vulnerable.
Species of elasmobranchs currently protected by CITES include the great white shark, whale shark, basking shark, and all species of sawfish. Porbeagles, oceanic whitetips, and hammerheads were proposed for CITES protections in 2010, but the measures failed.
Each of these proposals aims to list a species under CITES Appendix II, which requires that any international export of these species be certified as sustainable (including the issuing of permits). The discussion will take place next March at the 16th CITES Conference of the Parties in Bangkok, Thailand.