| How do you feel about the shark week controversy regarding the first documentary on the megladon? What should discovery channel do in regards to it? | Link to thelead.blogs.cnn.com |
| I think Discovery should apologize, but they won't. |
| There are so many true, interesting things related to sharks they could have done, why the hell did they have to start making shit up? I look forward to Shark Week every year because I like to learn about sharks.. This is disappointing. | Preach! |
| Hey David, I think its great you're doing this AMA, especially timely during a Shark Week frustratingly devoid of science. Thanks for all your tweets and FB posts about shark week, I'm so grateful for your voice of reason and humor! Do you think Discovery Channel will ever produce a Shark Week that shark scientists and conservationists can all in good conscience get 100% behind or is it a lost cause? Edit: spelling. | Yes! Did you see "Alien Sharks" last night? It was SO GOOD! Natural history, real science, no sensationalism. It's exactly what Shark Week used to be. |
| Are you really supposed to punch a shark in the nose if they attack you or is that just a myth? | If I punched you in the face, would you run away or punch me back? |
| question: I don't have anything to do with marine biology, I don't live near the coast, I don't know lots of kids to teach. What can I do to help you with conservation? | There are LOTS of things that you can do to help the ocean, even far from the coast! You're doing the most important one right now: asking questions and learning about it! |
| The single most important thing you can do, in my opinion, is to purchase only sustainable seafood, and to encourage others to do the same. The single greatest threat facing our oceans (including sharks) is unsustainable commercial fishing. |
| What's the most important job sharks do? | Sharks help keep the ocean food chain healthy. Where I'm from outside of Pittsburgh, we used to have wolves. Then we killed all the wolves. Now there are too many deer and not enough food for all of them. The deer leave their traditional habitat and cause billions of dollars of property damage each year. |
| $Billions?? What the hell do these Pittsburgh deer eat? If we only took care of this deer problem, we could double NASA's budget! | It's not just what they eat, it's what they destroy. Cars, fences, windows of homes. |
| 1) Do sharks really have 7 sets of teeth? | Some species of sharks have much more than 7 sets of teeth. Sharks can't go to the dentist, and they often bite big, tough animals. Teeth fall out and it's helpful to be able to replace them. |
| 2) Can sharks get cancer? | Sharks do get cancer. Every animal gets cancer. Even if they didn't, eating shark cartilage pills wouldn't help cure cancer, any more than I'd get better at basketball if I ate Michael Jordan. |
| Are you sure about every animal? | Basically every animal. And resistance isn't immunity. If you have cells, uncontrolled cell growth through mutation (i.e. cancer) is a possibility. |
| Hey David! Thanks for doing this AMA. Just want to say thank you. My girlfriend was a student of yours at SeaCamp when she was younger and your love for sharks shaped her into the scientist she is today. She's currently pursuing her masters degree in biological oceanography. I too work in the sciences and feel like communication with the general public about scientific issues is getting increasingly important. What's the hardest part of talking about controversial scientific issues with people who may not know a lot about them? | Hi! Tell your girlfriend hello for me. |
| The hardest part about communicating "controversial" science (which typically, these days, means climate change and alternative energy issues) is communicating uncertainty. Scientists often talk in terms of uncertainty, but when the public hears it, they think "scientists aren't really sure". |
| What is the craziest/scariest shark you have seen in person? What sharks are out there that haven't made it into the public eye? | I wrote my Duke admissions essay about a time in high school that I went SCUBA diving in a shark tank and stared down a 12 foot sand tiger shark. The most scared I've ever been, however, was the time I saw a bull shark on my first night dive. I was 15. And let's just say it's a good thing that my wetsuit was black. |
| I've always wondered though about those black wetsuits. Aren't they seal-looking like? I saw an ad the other day for a white and blue "camouflage" wetsuit and a striped "anti-shark" suit. Is there anything to that? | I'm skeptical, but they look awesome. |
| What is your favorite shark and why? | 1) Sandbar sharks. They were my Masters study animal have a special place in my heart. |
| What were obstacles you faced in your career path? | 2) I've been fortunate. I think my parents sort of always assumed that I'd grow out of this and become a lawyer or doctor, but they've been very supportive. Dad has even come on the research boat with me. |
| Is it possible for a thirtysomething to change careers and pursue this? | 3) Totally. |
| PS - I did my undergrad at Maryland, I'm going to miss the Duke games... | I'm sorry you went to Maryland, but nobody's perfect. |
| How do you feel about sharknado being so popular? | Pro. |
| Though the sequel title they chose, "SharkNado: The second one," is lame. I suggested "SharkNado Harder" |
| What about SHARKNADO: SHARKER, SharkNado Sharkie Goes West, SharkNado: A Good Day to Shark hard, SharkNado In Vegas: CardSharks, SharkNado in Space: Shark Trek, Thy Holy SharkNado: Noah's Shark | All better than "the second one" |
| What abilities/perks does a shark possess that a human should be jealous of? | Sharks have the ability to detect electromagnetic fields given off by prey. I feel like that would be pretty sweet. |
| What's one weird thing that not many people would know about a shark or sharks? | There are more than 500 species of sharks, and a new species of shark, skate, or ray has been discovered approximately every two weeks for the last decade. Most people only hear about the sharks that bite people. |
| There seems to have been quite an increase in shark attacks in recent years, at least around my area (Australia). Do you think that has more to do with increasing shark numbers, more people in the water or changes in weather? | Shark "attacks" increase slightly just about every year. The leading theory is that there are just more people in the water. |
| Do you think academic universities will ever recognize this kind of outreach as equally important to lab achievements? | I remain cautiously optimistic. I'm blessed with an adviser and department that encourage me to do online outreach. |
| I grew up in the Caribbean and some folklore said that sharks don't urinate in the wild thus making their bodies decompose very quickly after death and humans shouldn't consume their flesh. Is this based on any truth? | Very, very, very loosely. Sharks have urea in their tissues, which they use for osmoregulation. But sharks, like all animals, do excrete waste. |
| How difficult is it to collaborate with China for shark conservation considering shark fin soup is a delicacy there? | Attitudes are changing, particularly among the youth in China |
| Hey David! Thanks for doing an AMA. Other than marine science and sharks, what are you passionate about? What other field might you have gone into? | I feel like most little boys (and a lot of little girls) go through a shark thing or a dinosaur thing. I did both, and chose sharks. |
| I am the father of a future marine biologist. My fifteen-year-old son is going to a Marine Science magnet school in Palm Beach County. This summer he just kind of sat around, but next summer I want him to intern in a marine biology setting, I'm sure such opportunities exist. Could you recommend any program in South Florida in particular? | Check out SeaCamp, a marine science camp in the Florida Keys. I went there for 5 years and taught there for 2. |
| What are some myths about sharks that people believe? | People think of sharks as mindless killing machines, but they actually have larger-than-expected brains for their body size and lots of complex social and ecological behaviors. |
| What is the least scary thing about sharks? | Goblin sharks can be bubble gum pink. |
| How do you feel about duck-sized horses? | Thank you for this question that I definitely didn't plant via twitter after days of preparing an answer! |
| People seem fascinated by this, but despite the fact that I work with sharks, I'm afraid of ducks and geese. I was attacked by a Canada goose while I was a little kid. |
| I'd much rather fight duck-sized horses. |
| Are there any cultural norms within ocean science? For example, jokes that everyone gets, or common rites of passage? | See the first rule about Fight Club. For good measure, also see the second rule about Fight Club. :) |
| Hi David, I was wondering if you could comment on Tara Reid's recent discussion regarding the generation of whale sharks. Are these the offspring of a kinky dolphin-whale-shark-animal-mammal orgy as Reid implied, or is there an actual scientific evolutionary explanation for the "Whale shark?" | Tara Reid is...not an expert. |
| Whale sharks are sharks. Fish. Not whales. They're called whale sharks because they're really big. |
| What are some of the biggest misconceptions about sharks out there and what can those in the Ocean and Conservation world do to correct it? | Due in no small part to Shark Week, people are afraid of sharks. The best thing you can do is tell your friends and family the truth. |
| When you lecture or discuss why sharks are important, do you ever discuss why the math on shark attacks doesn't match up to the math? With hundreds of different types sharks, so few that have attacked people, and so many people who DON'T get attacked... | More people are bitten by OTHER PEOPLE on the New York City Subway each year than by sharks in the whole world. |
| What's a good statistic to share with people who are unreasonably scared of sharks? | More people are killed by vending machines, toasters, lawn mowers, and flower pots each year. |
| I live on Cape Cod, MA, and a few of our beaches have been shut down due to sharks. What's the reasoning behind sharks swimming closer and closer to the Atlantic shores every year? | One of the leading theories for this is seal population recovery in New England. More food = more sharks. |
| To what extent did the BP oil spill harm or help sharks, and how did that play out? I remember reading somewhere that sharks were in a feeding frenzy up the coast, because fish and other wildlife had nowhere to go because they had a wall of oil on one side and a wall of sharks on the other. | The BP Oil Spill has been devastating to marine animals, including some species of sharks. Pollutants and toxins "bioaccumulate", which means that they increase in concentration as you move up the food chain. |
| Do all these UN-interesting shark shows during shark week piss you off as bad as they do me? | I'll refer you to an interview I did in Wired this week. Link to www.wired.com |
| Have you ever or would you ever eat shark? What does it taste like? | Yes. It tastes like grouper, a very rich flavor. I don't recommend it because of sustainability issues, but the ones I ate were sacrificed for another scientist's research project, and there was no sense wasting it. |
| Do you have any predictions of what the oceans would be like without sharks? Does climate change put sharks at risk? | The loss of sharks will have a variety of negative ecological consequences. It won't be pretty. |
| Climate change isn't great for most animals, but sharks face a much, much, much greater threat from commercial overfishing. |
| Outside of this Megalodon chicanery, what was the worst, facepalm-inducing moment you've had when it comes to the media's portrayal of sharks? | "Top 10 Sharkdown" was pretty bad this year. Literally every sentence that wasn't an interview with a scientist had at least one wrong thing in it. |
| Also, if the Megalodon were to face a juvenile Sharktopus, who would win? | Sharktopus has steel-tipped tentacles, right? |
| Is it sustainable/okay to eat shark? | 1 in 6 species of sharks, skates, rays or chimeras are Threatened with Extinction, according to the IUCN Red List, with some species suffering reported population declines of over 90% since the 1970's. |
| However, some countries (the U.S. and Australia in particular) have relatively well-managed shark fisheries. |
| How much of your job is spent doing what you imagined you would before you entered the field? In your opinion, is that good or bad? Also, what is your favorite shark? | My typical day is probably pretty similar to most of your typical days. I answer e-mail and do data entry in Excel. However, I go on about 30-40 shark research trips a year, and those are awesome. If you're with a high school class, community group, etc, you should come RJD.Miami.Edu/participate |
| You don't get to be a shark scientist overnight, and you don't get on the boat until you've put in a lot of work. What path did you take to get to where you are now from an education/training/lab standpoint? | I studied biology and marine science at Duke University, and got my Masters in Marine Biology at the College of Charleston. |
| What shark do you think is the most badass And why? | Greenland sharks have been found with polar bears, the largest land predator on Earth, in their stomach. |
| What is your favorite beer at WetLab? | Whatever's on special. There are no bad choices for beer at WetLab. |
| WetLab, for those who don't know, is the on-campus bar at the University of Miami's marine lab. The motto is "providing scientific support services". |
| Hi David, thanks for doing this! In your opinion, when did the trouble with Discovery Channel's Shark Week really start? Do you think the vocal frustration directed towards the current state of Shark-related programming is a recent development, or has it been bubbling under the surface for a while in marine biologist circles? | Shark Week used to be about science, about inspiring wonder towards the natural world. Some of it, like "Alien Sharks" last night, still is. |
| What is the single fact that makes sharks the most amazing animal in the planet? | There were animals recognizable as sharks swimming in the oceans many millions of years before there were dinosaurs. These are ancient vertebrates. |
| Do sharks only exist to a certain level of depth in the ocean? Also, how come shark isn't as common as a food source as other undersea life? | Sharks can go pretty deep, but not to the absolute bottom of the deepest parts of the ocean. |
| Hey David! With so many shark species in decline, is it becoming harder for scientists to find enough live samples to conduct their research? | To some extent. I've been on about 60 sampling trips with my lab here in Miami, and we've caught 0 sharks on 4 of them. It depends on the research question, as some require higher sample sizes than others. |
| Hey David, I'm an undergrad at the University of Miami studying Marine Affairs and Anthropology. I've been interning at the Cape Eleuthera Institute doing shark research for the last two months. Besides applying for an internship with RJ Dunlap what other ways can I get involved with shark conservation in Miami? Thanks, Alice. | Hi Alice! I may be biased, but applying to work with our lab is probably your best bet for hands on shark research in the Miami area. |
| What do you know about the correlation of heightened stress hormones in sharks linked to decreased immune function? I know that increased and prolonged levels of stress in mammals weakens the immune system and am wondering if something similar occurs with sharks. | I'm not trained extensively in stress physiology, but heightened stress hormones have a variety of sublethal effects and I believe that a weakened immune system is among them. |
| With the recent discussions on the decoding of the Mammoth genome, do you think it would be wise to clone and resurrect the species (I ask because you study living creatures and their place in the world) and if so, are there any shark species you would like to see brought back? | I'd prefer that we focus our efforts on not letting current species go extinct. Many extinct animals became extinct because their food source or habitat isn't there anymore, and de-extinction won't fix that. However, I'd love to see a Stellar's Sea Cow (basically a giant manatee), an animal that sailors hunted to extinction in just a few decades. |
| Have you had any scary encounters with sharks? Like one tried to attack you or a student/coworker? | I've never been bitten, and I've interacted with over 3,000 animals both in the water and on the boat. I have hundreds of pictures of sharks, and most are of them swimming away, because that's what they do when they see us. |
| I wanted to know what your least favorite shark/marine animal is. | My least favorite shark at the moment is the nurse shark, because one recently slapped my ass so hard with it's tail that I couldn't sit for three days. I also don't particularly care for dolphins, but that's longstanding. |
| also, if you had a pet shark what would you name it? | If I had a pet shark, his name would be Steve. |
| As a shark expert, what was your professional opinion of the movie Sharknado? | Almost as good as "mega shark vs. giant octopus" |
| Do you think that sharks matter in terms of ecosystem stability and resilience? Could you provide some peer reviewed research to support where you think the weight of evidence lies. | Here's a good review of shark ecosystem importance that's freely available online: Link to www.fmap.ca |
| Are there some potential benefits to low shark abundance that outweigh the benefits of high shark abundance? | There are no benefits to low shark abundance that I'm aware of. |
| What are some things that you would suggest to a college student who wishes to follow in your footsteps? | Study math and science, volunteer in labs, read, read, read. |
| As someone who surfs, what do you think about the new "Anti-Shark" wetsuits? Does any of your research back up their claims? Link to www.foxnews.com. | I'm skeptical of their effectiveness, but they look awesome. |
| What has been your favorite place in the world to dive? | I like Sylvia Earle's answer to this, "anywhere 50 years ago" (i.e. before overfishing. |
| But the wreck of the Yongala in Australia was my favorite. |
| What do you think about Nelson the Shark found in the subway a few days ago? | New Yorkers, man. Weird folk. |
| Also, I've always wanted to pet a shark to see how they feel. DETAILS MISTER. | Sharks are smooth in one direction and feel like sandpaper in the other direction. |
| Mega shark vs giant octopus. Sharktopus. Shark in venice. | Loved 'em, particularly mega shark vs. giant octopus. |
| Hey David, thanks for the AMA. I lived in the caribbean for a couple of years and was fortunate to encounter nurse sharks and reef sharks diving and snorkeling, on multiple occasions, naturally (not in chummed water or a feeding frenzy), and not once did I feel threatened. Watching shark week yesterday, there was a show about people who had, unfortunately, lost limbs to shark bites. That was it. The whole premise to the show was, people scared who had limbs amputated as a result of a shark attack. I thought shows like that one and the megladon "documentary" are doing way more harm by instituting fear of sharks. What are your thoughts on shows highlighting attacks and instilling fear that there is a large carnivorous shark prowling the oceans? | I'll refer you to a recent interview I gave in Wired Link to www.wired.com |
| Would you rather fight a shark sized duck or 100 duck sized sharks? | 100 duck sized sharks. |
| I was snorkeling in Hawaii and I saw a sea turtle. I was ecstatic at first but then I was terrified because my cousin (who lives in hawaii) told me that wherever there are turtles, there are most likely sharks. How terrified should I have been? | Not at all. There probably were sharks nearby, though (not because there are turtles, but because you're in the ocean). |
| Hi David, I have been (and would love to go again) shark cage diving with great whites in South Africa: do I risk disturbing the animals in their environment or even worse getting them used to humans when doing so or is it an acceptable practice? | There are dive operators that are extremely responsible. |
| Who are your heroes and mentors? Who inspired you to go into science, and who inspires you today? | I liked the ocean long before I knew I could study it professionally. One of my heroes is Eugenie Clark, who I recently met (and, despite being in her late 80's, still hangs out at bars with grad students and is generally awesome). |
| What's your hypothesis for the White Shark Cafe? | The leading hypotheses for the White Shark Cafe (as with just about any aggregation site for animals) deal with reproduction or feeding. |
| Also have you tried Hakarl? | I have not tried Hakarl, but I'm an adventurous eater and would probably try a bite. I expect it's not as tasty as sea turtle. |
| Just out of curiosity, is the research site in Bimini still ongoing? | Yup. |
| What is the ultimate impact mercury pollution will have on Sharks and other apex, ocean predators? | Mercury does bioaccumulate, moving up the food chain. It may impact shark behavior and physiology, but I don't think this has yet been confirmed. |
| Can we assume mercury poisoning will lead to erratic behavior for sharks, as it does in other animals? | The biggest threat facing sharks is commercial overfishing, though. |
| Why do sharks matter? | As top predators, they help keep the ocean ecosystem in balance. |
| Have you ever eaten sharkfin soup? Would you support, or more like not be against, eating sharkfin if the process of obtaining the fins weren't so inhumane (like fish farming)? | Many shark fins are NOT obtained in the inhumane method you allude to, shark finning. But the issue isn't how humane it is, the issue is the effect on shark populations. Overfishing is a big problem. |
| Hey David, if I cut the bottom of my foot on let's say a shell in the ocean and I bleed, at what distance could a shark pick up on the blood scent? Thanks! | Scent doesn't work at distance. Molecules need to actually touch the chemoreceptors (which means that when you smell something nasty, tiny particles of that something are physically in your nose). But sharks can detect blood in very low concentrations. |
| Does Megalodon exist? | Not anymore. They've been extinct for between 1.5 and 2 million years. |
| David! Hey how are you? My name is David as well and I am currently am a macroinvertebrate biologist at Reedy Creek Improvement District on Disney property. I have a degree in aquatic science and fisheries from SUNY Environmental Science and Forestry college. You see I have worked in freshwater my whole life and my pipe dream is to do some coral restoration or something with sharks and other larger marine animals. My question to you is now that I am gaining my experience as a biologist, how do I progress to the marine world from where I am now? Is it harder due to my freshwater background? ORRR, whats it take to work under you:)? | Our lab takes interns. RJD.Miami.edu/participate. |
| Freshwater background won't harm you. You have scientific training and research experience. |
| What's the most intelligent thing Sharks are capable of? | We put GPS satellite tags on some tiger sharks in the Bahamas. They swam over a thousand miles into the middle of the Atlantic ocean...and then came right back to the same beach we tagged them at. |
| How many species of sharks do you think that we have still yet to discover? | Scientists have discovered a new species of shark, skate, or ray about every 2 weeks for the last decade or so. |
| Did your love for sharks have anything to do with "Jaws" and the like? I saw it when I was young, and ever since I've had a strange fascination with them, albeit a slight fear too. Would you say fear and respect go hand in hand? | Sure. Jaws is a great movie, and one of the most accurate depictions of a marine biologist in any move I've seen (besides mega shark vs. giant octopus) |
| What is the furthest North or South Sharks have been spotted? I know they are mostly warm water, but curious about this aspect. | They're not mostly in warm water. There are sharks under the Arctic ice (Greenland sharks). Incidentally, greenland sharks have been found with POLAR BEARS AND REINDEER in their stomachs. |
| What would be the best course of action if you actually (against all odds) had a shark that wanted to eat you? Are there any of those tricks that actually work? | Sharks don't eat people. We're too bony, there's no nutritional value. |
| Here's a guide to "surviving the shark attack that won't happen" in Smithsonian magazine that includes an interview with me. Link to blogs.smithsonianmag.com |
| Hi David. What is your opinion on keeping sharks in an aquarium for human exhibition? Someone on reddit pointed out to me yesterday that the aquarium opening in my city in a couple of months is having 10 tiger sharks captured and brought over from the states. Do you think there are any upsides to confining highly intelligent creatures in poor living conditions that decrease their lifespan that people opposed to such practices might be overlooking? Thank you! | Fish aren't really "highly intelligent", although sharks are smarter than most people think they are. |
| Any disadvantage to the individual animal is, in my opinion, balanced by the benefit to the species of getting people to care about sharks by seeing them up close at an aquarium. |
| Which spots around the world appear to have the highest densities of large sharks (great white, oceanic whitetip, etc)? The only answer I've seen is Seal Island along the South African coast, but I know there must be other places that are hotspots. I've always wondered this. As far as lowest densities... would that be the Arctic Ocean? | There are sharks basically everywhere that there's salt water. Densities vary based on which species you're interested in. Seal Island is a common study spot for adult great whites. Cat Island in the Bahamas is a common study site for oceanic whitetips. |
| Considering the amount of press that sharks get and the amount of 'experts' Discovery seems to roll in every year for a week, it always occurs to me that there is only so much to be learned about these sea beasts. Maybe that is why Discovery decides they need to expand to science fiction to cover some of their prime Shark Week spots. Is there any sense that the shark research field is saturated? Clearly, there is much we don't know about sharks, but perhaps there are other areas of marine biology which get far less attention that need it? | Not at all! I just returned from the American Elasmobranch Society (the largest professional association of shark scientists) conference, and I saw over 100 presentations of which maybe 60 would have made for fascinating (and new) documentaries. Shark Week covering the same nonsense over and over doesn't mean there's nothing new to cover. |
| Why don't we hear about more people being fully consumed by sharks? Shark week shows quite a few instances where sharks will bite someone and then retreat. Even if we aren't their natural prey why skip out on the meal you've just started? | We're too bony. I've seen some calculations that show that it would take more energy to digest a human than a shark would gain in nutrition. |