The deep sea is one of the largest, least explored, and most unique ecosystems on the planet. An enormous variety of weird and wonderful creatures make the deep sea their home, including many species of sharks. A new project, headed up by our friends at the Cape Eleuthera Institute, hopes to learn more about these sharks.
According to Edd Brooks, CEI’s shark research and conservation program manager,
“About half of all known species of sharks make this cold, dark high pressure environment their home, and new deep water species are being described all the time. The issue we are currently facing is that basic information about the taxonomy, biology and ecology of these animals is virtually non-existent, yet they are already being harvested by commercial fisheries. The little we do know about deep water species is worrying, in that they are thought to be more sensitive to fishing pressure than all other fish – and look what we have managed to do their more robust shallow water cousins already. The worry is that in some areas, we are already be losing species before they can be described taxonomically.”
Continue reading Medusa: Scientists document rarely seen deepwater sharks using baited video cameras
Florence the "vegetarian" nurse shark eating lettuce. Photo courtesy Jamie Turner, Sea Life Centre Birmingham
Between my well-documented love for sharks and my famously vegetable-less diet, a recent story about a “vegetarian shark” was destined to be e-mailed to me by friends and family. For those of you unfamiliar with the story, a captive nurse shark at an aquarium in the United Kingdom has been eating lettuce and celery, and refusing to eat normal nurse shark food (crustaceans and fish). As a result of this…no, wait, that’s pretty much the whole story. This animal has been dubbed “the world’s first vegetarian shark”, and my twitter and Facebook feeds have been full of people misinterpreting what this means even worse than the original media coverage did.
This is not a case of an animal “changing the reputation of sharks worldwide, and in the greenest way possible”, as reported on EcoRazzi. This is not a case of “even sharks realizing that vegetarianism is the most environmentally friendly diet”, as some have claimed. The reality is much more troubling. Following an incredibly traumatic experience (a 2009 surgical procedure to remove a rusty hook lodged in the digestive tract), an animal has radically changed its natural behavior in a way that isn’t healthy.
Yes, unhealthy- regardless of your views on the health benefits of a vegetarian diet, I’ve been assured by friends who do eat vegetables that lettuce and celery don’t have a lot of nutritional content. Fortunately, the aquarium staff at the Birmingham Sea Life Centre is aware of this and is working hard to get this animal the nutrition it needs. According to the press release (available online here), aquarium curator Graham Burrows said “we’re having to hide pieces of fish inside celery sticks, hollowed out cucumbers and between the leaves of lettuces to get her to eat them”. One could argue that the fact that the shark is still eating fish (although hidden among veggies) means that it isn’t a vegetarian at all, but that isn’t really the most important point here.
Continue reading Traumatized animal radically changes diet and behavior in an unhealthy way: the real story of the “vegetarian shark”
Earlier this week, I asked my twitter followers what they thought about shark fin bans, which prompted a long and stimulating discussion. What follows is my first attempt at “Storify”, shared in the hopes that the discussion can continue here.
As I’ve said before, I’m not a big supporter of shark fin bans because they don’t allow for sustainable, well-managed fisheries to supply the market. Additionally, they promote the common (and false) belief that shark fin soup is the only major problem facing sharks, and don’t address many of the other important issues associated with shark conservation.
Instead, I favor a comprehensive approach to shark management, including requiring that sharks be landed with fins attached (i.e. a ban on “finning” but the fins can still be used if the shark is landed whole), special protections for threatened and endangered species, science-based fisheries quotas for species that can sustain fishing, time/area closures or gear restrictions when necessary, and careful monitoring (including requiring that all fishing nations report the species composition of their catch).
Check out the great discussion if you missed it, and let me know what you think of this important issue in the comments of this post.
Continue reading Shark fin bans: A storify of this week’s twitter discussion
Jordan Nikoloyuk is the Sustainable Fisheries Coordinator of the Ecology Action Centre, a membership-based community environmental organization based in Nova Scotia, Canada. The Marine Issues Committee of the EAC was founded in 1995 after the collapse of the Atlantic Canadian groundfish stocks and works towards conserving and protecting marine ecosystems and maintaining sustainable fisheries and vibrant coastal communities.
As part of its sustainable seafood work and through its Friends of Hector campaign - www.friendsofhector.org - the EAC has participated in many Marine Stewardship Council assessments for Atlantic Canadian fisheries and encouraged retailers to support certified fisheries. Jordan has written this guest post to share his recent experiences with a certification that has left the EAC and other conservation organizations wondering whether seafood certification can contribute to sustainable fisheries management in the long term, or if the conflict between keeping an eco-label rigorous on the one hand and expanding its market appeal on the other is just too difficult to manage. What do you think?
The best way to buy seafood responsibly is to read a sustainable seafood guide and ask your retailer the two big questions: where is this from and how was it caught? When getting these answers is tough, many people turn to eco-certifications and labelling. Despite some increasingly controversial certifications, the Marine Stewardship Council (MSC) is considered to be the most trusted and reliable label, but how many unsustainable fishery certifications will it take to ruin this credibility?
Last week, after lengthy and widespread opposition, the MSC approved certification of the Atlantic Canadian longline swordfish fishery, which catches 100,000 sharks and 1,400 endangered sea turtles every year. The Ecology Action Centre spent almost two years working to oppose this greenwashing. Now we are left asking: how can we promote sustainable fisheries with organizations the size of the MSC working against us? When a definition of sustainability is so weak that it lets the status quo continue, can this be seen as an effective ‘market-driven solution’?
Continue reading Guest post: Swordfish, certifications, and sustainable seafood
John Shepherd once said that counting fish is like counting trees, except that fish move and you can’t see them because they’re underwater. This is true with sharks as well. It’s basically impossible to know how many sharks there are. Fortunately, a variety of methods exist that can be used to determine population trends. In other words, even if we can’t know how many sharks there are, we can tell if there are more or less than there used to be. Presented here are brief descriptions of some of these methods and the conclusions of major shark conservation studies that used them. Though no one method is perfect, the fact that so many different methods have such similar conclusions is quite telling.
Continue reading How severe are shark population decreases, and how do we know?
WhySharksMatter and a whale shark at the Georgia Aquarium
The world’s largest shark eats only plankton, couldn’t bite a human if it wanted to, and is one of the few sharks that could be reasonably described as beautiful. Globally, SCUBA divers pay an estimated $50 million each year for the chance to swim with these incredible fish. Their long migrations through international waters makes international cooperation necessary to protect them, which is particularly important because the 30 years it can take for these animals to reach reproductive maturity means that populations will take a long time to recover if they are overexploited. They’re listed by the IUCN Shark Specialist Group as Vulnerable globally. Between their charismatic nature, their inability to harm humans, and their value to ecotourism, it should be easy to convince governments to protect whale sharks *, making two recent reports all the more shocking.
Continue reading Bad news for whale sharks: The world’s largest fish are being killed for bait and billboards
Image taken from the South Florida shark fishing club online forum. Photographer undisclosed. I have blocked out the angler's face to protect his identity
Update: The angler who originally caught the shark has responded. Please see below.
On February 5th, while standing on a beach in Miami, a fisherman caught a 14 foot great hammerhead shark. According to his account, ”we had it beached within an hour of hooking it. The fish weighed too much her girth was huge. Just the 2 of us wasn’t enough to get it out of the water….We snapped some pictures with our dying camera, measured it at 170 inches and spent the next hour walking back and forth with HER reviving her…it swam off slow and steady”
While this might appear to be a simple case of catch-and-release recreational fishing, it is not. My lab and I are supporters of sustainable catch and release fishing. However, it is important to note that since January 1, 2012, great hammerheads (an IUCN Red List Endangered species) have been a protected species in Florida state waters and have additional legal protections. The Florida code indicates that:
“(1) No person shall harvest, possess, land, purchase, sell, or exchange any or any part of these species:
…(k) Great hammerhead – Sphyrna mokarran.
…(3) “Harvest” means the catching or taking of a marine organism by any means whatsoever, followed by a reduction of such organism to possession. Marine organisms that are caught but immediately returned to the water free, alive, and unharmed are not harvested”
…(5) “Land,” when used in connection with the harvest of marine organisms, means the physical act of bringing the harvested organism ashore” Florida code section 68B-44 (Emphasis mine)
In this incident, the shark was brought ashore. We can infer from the statement “the fish weighed too much her girth was huge. Just the 2 of us wasn’t enough to get it out of the water” that the fisherman attempted to pull it all the way out of the water, but was unable to do so (an important legal distinction) . Instead, he ended up beaching it, bringing it so far out that it could not move or breathe. The angler did not immediately release the animal. According to the angler’s account, it was measured and photographed prior to the attempt to resuscitate it. The shark was not released alive and unharmed. By the angler’s own admission, it took over an hour of resuscitation before the animal was able to even swim away slowly.
Continue reading Florida angler catches (and likely kills) Endangered great hammerhead shark
I want to apologize to our regular readers for stating something that should be incredibly obvious. Sharks in in no way connected to the global supply of atmospheric oxygen. If every single species of shark went extinct, there would be a variety of negative ecological effects, but a reduction in the global supply of atmospheric oxygen would not be among them. There is not a shred of scientific evidence supporting the idea that the loss of sharks would affect our oxygen supply- not a single scientific paper, not a single technical report. I’ve attended a dozen scientific conferences focusing on marine ecology or shark biology (including three international conferences) and I’ve never seen or heard of anyone presenting or even discussing this. To the best of my knowledge, not a single person who has authored a scientific paper or technical report supports this idea. Despite the complete lack of any kind of credible evidence, and despite many recent blog posts thoroughly debunking it (see here here here here here here and here ), this pseudoscience just won’t die.
The premise of the sharks and oxygen claim is as follows:
Continue reading “Sharks create oxygen”: A scientific perspective
Earlier today, the Marine Conservation Science Institute launched a new iPhone and iPad app focusing on great white sharks. The app, called Expedition White Shark , includes numerous features that let users learn more about these amazing animals.
A game (called “Shark Life”) lets you learn about the life history of great white sharks by controlling a virtual baby great white. Users explore the marine environment near Southern California white eating fish and avoiding threats like gillnets and pollution.
A “news” interface lets you keep up to date on some of the latest exciting discoveries the Marine CSI team makes, and you can learn more about great whites from the “facts” tab. The app also includes numerous photos and videos of great whites and the research team in action.The coolest feature this app contains, however, is the ability to track satellite-tagged great whites.
Continue reading New app: Learn about great white sharks while supporting research
Photo credit: study author Pascal Geraghty, New South Wales Department of Primary Industry
Last week, a team of 10 Australian scientists announced that they had found the world’s first “shark hybrids”, offspring of individuals from two different shark species which had interbred. During a routine survey of Australian marine life, 57 sharks were found that physically resembled one species of shark, but had genetic markers inconsistent with that species. Subsequent genetic investigation revealed that these 57 animals were hybrids between common blacktip sharks (Carcharhinus limbatus) and Australian blacktip sharks (C. tilstoni).
Some of these hybrids were “F1″, meaning that one parents was a common blacktip and one was an Australian blacktip. Others were “B+”(backcrossed), which means that one parent was a common blacktip/Australian blacktip hybrid, and the other was a “purebreed” of one of those two species. According to the study’s lead author, Dr. Jess Morgan of the University of Queensland, ”our genetic marker tells us that these hybrids are ‘at least’ F1, and that these animals are reproductively viable and can produce an F2…the hybrids may be generations past F2 but the existing genetic markers can’t distinguish how many generations past the second cross have occurred.”
Continue reading What hybrid sharks mean (and don’t mean) for climate change and evolution: fact-checking the media coverage