World of Sharks

The international trade in shark fins is a behemoth; vast, complex and difficult to disentangle. But for molecular and forensics expert Dr Diego Cardeñosa, one of the most powerful tools we have to tackle the fin trade is the tiniest part of a shark: their DNA. In this episode, we take a deep dive into Diego's research, which has been instrumental in understanding the nuances of the fin trade and securing better regulations for this billion-dollar industry. This includes the development of a portable, easy-to-use and inexpensive DNA ID kit (the "lab-in-a-backpack") that can help local officials identify endangered and protected species from just fragments of shark fin - all for under $2. We also talk about the problems with implementing international policy at a local level, the scale and complexities of the trade, and whether Diego is seeing any shifts in how the trade operates - for better or for worse. Links Shownotes: www.saveourseas.com/worldofsharks/podcast Diego on Instagram: @diegocardenosa https://saveourseas.com/project-leader/diego-cardenosa/ https://case.fiu.edu/about/directory/profiles/cardenosa-diego.html If you want to dive deeper, you can find links to Diego’s research here .

Few sharks capture the imagination quite like the thresher shark. They are well-known for their cartoonish appearance, “anxious-looking” faces and seriously cool hunting technique. But in scientific terms, we know very little about them – despite their endangered status. Rafid Shidqi is on a mission to change that. For the last eight years, he has led groundbreaking research on the elusive pelagic thresher sharks of Alor, Indonesia, whose preference for deep, pelagic habitats make them extremely difficult to study. In 2018, Rafid started the non-profit Thresher Shark Indonesia, working within remote, shark-dependent fishing communities to better understand and protect the species. Through acoustic and satellite telemetry and socio-economic studies, Rafid has made vital discoveries about not only the movements and behaviour of pelagic threshers, but also the communities who rely on them to make a living. Rafid’s story isn’t just about conserving a cool species – it’s also about empowering communities, opening pathways for local youth through conservation leadership, and finding sustainable solutions for shark-dependent fisheries. Find out more: https://threshershark.id/en/ (@threshershark.id on instagram) and @rafid.shidqi Shownotes: www.saveourseas.com/worldofsharks/podcast Follow us on socials! @saveourseasfoundation

This episode is an extra special one – it’s our 100th! To celebrate this milestone, our host Dr Isla Hodgson looks back across half a decade and 100+ hours of conversations about sharks with the people who know them best. And, we hear messages and bonus shark stories from some friends of the pod. Transcript and shownotes: www.saveourseas.com/worldofsharks/podcast . This episode features the voices of (in order of appearance): Dr David Shiffman [5.10] Dr Helen Scales [5.51] Dr Luz Saldana Ruiz (en Español) [13.46] Jillian Morris-Brake [16.51] Steve Backshall [21.59] Dr Jaime Penadés Suay (en Español) [26.53] Craig Foster [32.07] Dr Hollie Booth [38.50] Dr Brit Finucci [39.20] Dr Jack Cooper [41.50]

Parasites have a bad rep. We often see them as harmful, exploitative, and just plain icky. But in the shark world, parasites are much more than just irritating hitchhikers. They are ecosystem engineers and important indicators of the health of not just sharks, but the entire ocean. And studies are starting to show some may actually benefit our sharky friends. Isla met with shark parasitologists Dr Bjoern Schaeffner and Dr Jaime Penadés Suay at Sharks International, Sri Lanka, where they were hosting a workshop on shark parasites. Together, they discuss what parasites we might find in and on sharks, their critical ecological and biological roles, and why on earth we should care about them, before heading to an outdoor dissection in the seaside city of Negombo to explore, hands-on, the world inside of sharks. Shownotes: www.saveourseas.com/worldofsharks/podcast

We're diving back into our mailbag to answer more of your burning sharky questions! In this episode we address all sorts of fascinating queries such as how bioluminescence evolved in sharks, which species are capable of breathing while they’re not swimming, and whether sharks are really older than trees. Plus, we take deep dives into several awesome species – great white sharks, grey reef sharks, pocket sharks and of course, James’ favourite, the velvet belly lantern shark. Specific question timestamps: Q1: Are there any shark species that are showing signs of adapting well to climate change? [3.36 – 10.21] Q2: Has there ever been more observations of any of the two species of Mollisquama (pocket sharks)? [10.31 – 13.20] Q3: How did bioluminescence in species like the pocket shark evolve? Was it independent, or did their last common ancestor have bioluminescent fluid? [13.40-15.11] Q4: We rarely hear about white sharks in the vicinity of South America, either ocean, with the exception of seasonal migrations of NA white sharks into the US South Atlantic coast and Caribbean. My question is: why not? [15.22 – 21.49] Q5: Which shark species can stay still and breathe through buccal pumping? [21.59-28.44] Q6: Which species of shark and ray are most closely related? [28.54 – 37.50] Q7: What is the most surprising thing you’ve learnt in your career (when you first started, vs. most recently)? [37.58 – 44.58] Q8: Shark [bite incidents] often go unreported for various reasons despite the best efforts of educational institutes to accurately record them. What do you think the real number of global [incidents] might be? [45.06-52.14] Do you have any questions you'd like researched and answered on the pod? Get in touch! You can email isla@saveourseas.com or message us on socials: @saveourseasfoundation.

Art has the power to change perspectives, spark dialogue, and raise awareness of the complex issues facing our ocean. This is exactly why PangeaSeed was established. Since its inception in 2010, PangeaSeed has brought together local artists and their communities to collaborate on large-scale, vibrant public artworks on the walls of their towns and cities, depicting the ocean, her inhabitants, and the challenges she faces, in line with PangeaSeed's mission to bridge art and science. Over the last decade, over 500 murals have been created in locations across the world. Ahead of their travels to Seychelles, Isla sat down with executive director and director of operations for PangeaSeed, Tre and Akira, to discuss the intersection of art and ocean conservation, the importance of community and connection, and how sharks started an entire movement. You can find out more about PangeaSeed here www.pangeaseed.org, or on social media (@pangeaseed and @seawalls_). Shownotes: www.saveourseas.com/worldofsharks/podcast Follow us on socials! We are @saveourseasfoundation across all platforms.

In August 2025, a paper published in the journal Frontiers in Marine Science suggested that ocean acidification could negatively impact a shark's most useful tool: their teeth. We speak with the papers lead author, Max Baum, about this research, and what the findings could mean for the sharks of tomorrow. Plus we take a deep dive into the wonders of shark teeth, and meet a decidedly unbothered tiger shark named Farida. You can read the paper we discuss in this episode here: Simulated Ocean Acidification Affects Shark Tooth Morphology You can also follow Max on Instagram (@maxbaum_insights) and discover more about his work here: www.ocean-insights.org. Full shownotes: www.saveourseas.com/worldofsharks/podcast . Find out more about us by following @saveourseasfoundation across all platforms!

Sharks have been around a long, long time (over 450 million years!). But how did they evolve into the extraordinarily diverse and successful group of animals that we have today? On today's episode, we meet palaeontologist and author of The Secret History of Sharks, Professor John Long, to discuss a thrilling story of evolutionary experimentation, fossilised clues, and above all, survival. The Secret History of Sharks is available now: https://www.quercusbooks.co.uk/titles/john-long-2/the-secret-history-of-sharks/9781529427356/ Shownotes: www.saveourseas.com/worldofsharks/podcast

The Maldives has served as a shark sanctuary for 15 years, and is now one of the most diverse regions for sharks and rays in the world. But with great success comes a new problem: conflict with humans. Fishers are reporting a loss of some of their catch to sharks, an issue known as depredation. For her PhD, SOSF project leader Mina Hatayama is seeking to understand depredation in the Maldives, studying shark behaviour and how it impacts local fishers and their attitudes towards sharks. She will also be asking the very intriguing question of whether hotter sharks are hungrier sharks, exploring the potential role of ocean warming in these increased depredation incidents, as well as working closely with the local fishing community to understand their perspectives and co-develop sustainable solutions. In this episode, we dive into the challenges of humans and sharks sharing space and resources. It’s a really insightful conversation that weaves together all kinds of issues, from human attitudes and shifting baselines, to the influence of global threats such as climate change on human-wildlife interactions. We also discuss how complex and delicate these situations can be, and the realities of navigating an interdisciplinary project. Read more about Mina’s ongoing SOSF project here https://saveourseas.com/project/attitudes-and-costs-from-a-new-conservation-challenge/ and here https://www.fishandfisheries.com/minahatayama. Shownotes: www.saveourseas.com/worldofsharks/podcast

Sometimes called the 'couch potatoes of the sea', nurse sharks are famous for their laid back attitude to life spending most of their days cosied up in piles, napping. But their gentle, docile nature doesn't make them any less special. In this episode, we sit down with SOSF project leader and PhD Researcher Sergio Madrigal Mora - who has spent a lot of time hanging out with the Labradors of the shark world - to discuss how nurse sharks are perfectly adapted to life in the tropics and why they form 'cuddle huddles' on the sea floor. And, we learn more about Sergio's research into the influence of changing temperatures on the movements of Pacific nurse sharks in Costa Rica's St Elena Bay. Shownotes: www.saveourseas.com/worldofsharks/podcast You can follow Sergio on Instagram: @sergiomm_77 or @tiburones_ucr. You can find us across all platforms as @saveourseasfoundation. Papers mentioned in this episode: https://www.int-res.com/abstracts/meps/v750/meps14733, https://www.sciencedirect.com/science/article/pii/S0022098125000589, https://connectsci.au/mf/article/75/2/MF23162/61130/Long-distance- dispersal-of-the-endangered-Pacific

We know sharks have incredible senses, but just how good is their eyesight? In this episode, we explore the world through a shark's eyes with fish vision expert Dr Lily Fogg. How does fish vision compare to our own? How do the eyes of a fish living on a vibrant coral reef differ from those hanging out in the murky depths? And do sharks see in technicolour, or multiple shades of grey? We also take a dive deep into Lily's most recent research, which investigated the eyes of the world's longest living vertebrate: the greenland shark. Her findings challenge a commonly held perception of these ancient creatures, and push the boundaries of what we thought was physiologically possible... Shownotes: www.saveourseas.com/worldofsharks/podcast You can read the full study on greenland shark vision here: https://www.nature.com/articles/s41467-025-67429-6 You can find SOSF on social media by searching for @saveourseasfoundation across all platforms.

To kick off our new season, we're diving into our mailbag to answer your burning questions! From speedy sharks to mimicry and even fossilised shark poop, we're leaving no stone unturned... Thank you to everyone who sent in a question - we had so many we ended up doing two episodes! Part 2 will be out later in the season. Questions answered (with timestamps): 04.54: Do any sharks, other than megamouth sharks, use mimicry? 14.15: Are megamouth sharks regional endotherms? 19.22: Do magnetic shark deterrents work? 30.28: Are hydrothermal vent species able to move around? 32.54: How do we know which prehistoric shark fossilised poop came from? 41.13: How do basking sharks find their food? 47.49: Which is the fastest shark? 52.34: If you could pass one international law to help sharks, which would it be? You can also read our answers in the shownotes: www.saveourseas.com/worldofsharks/podcast

The conversations that shape the fate of sharks and rays rarely happen in quiet laboratories or out at sea. More often, they unfold in fluorescent-lit halls, behind nameplates and microphones, inside sprawling congress centres where global decisions about nature are made. At the IUCN World Conservation Congress, surrounded by thousands of delegates debating the future of biodiversity, host Isla sat down with SOSF Scientific Advisor Sarah Fowler and Chair of the IUCN Shark Specialist Group, Dr Rima Jabado, to discuss how far we’ve come in the race to save sharks and rays from extinction – and what steps we need to take next to ensure their future on this planet. Shownotes: www.saveourseas.com/worldofsharks/podcast Find out more about the Save Our Seas Foundation (SOSF) here: www.saveourseas.com or follow @saveourseasfoundation across all platforms.

Did you know that there are over 60 species of shark who are luminous? In this episode, we learn all about the sharks who light up the darkness of the deep sea. How are they able to produce their own light? And why have they evolved the ability to glow? We are joined by Professor Jerome Mallefet, an expert in bioluminescence who has studied some of the most fantastical species on earth, including a shark with lightsabers on its back - the velvet belly lanternshark - and the largest known luminous vertebrate, the kitefin shark. Shownotes: www.saveourseas.com/worldofsharks/podcast Find us on socials! @saveourseasfoundation

How do sharks locate prey when they’re roaming the open ocean? What does a shark ambush look like? Are sharks capable of hunting cooperatively? And why do cookiecutter sharks take on prey much larger than themselves (including submarines!)? We are asking all these questions and so much more this week as we dive into the fascinating world of shark behavioural ecology to better understand foraging and hunting, with marine biologist and co-lead of the Predator Ecology and Conservation Lab at Florida International University, Dr Yannis Papastamatiou. Find out what it was like to dive with over 300 blacktip reef sharks at once (in the dark), what sharks and seabirds have in common, and why white sharks might be more social than we think. You can follow Yannis (@yannispapastamatiou) and the PECLab (@peclabfiu) on Instagram. You can find us across all platforms: @saveourseasfoundation. Shownotes: www.saveourseas.com/worldofsharks/podcast

It’s spooky season, and what a great excuse to visit our friends in the dark; the deep-sea sharks, rays, skates and chimaeras! We’re joined by fisheries scientist and deep-sea legend Dr Brit Finucci to go on a journey into the darkness – a far from barren landscape filled with weird and wonderful creatures. We’ll meet icons like the small-but-ferocious prickly dogfish, the luminous lanternsharks, the ancient and toothy frilled sharks, and a ghost shark called Colin, who just so happens to be new to science. Shownotes: www.saveourseas.com/worldofsharks/podcast If you want to learn more about ghost sharks, Brit has co-authored a new book all about them! Ghost Sharks: A Fully Illustrated Guide to the Chimaeras of the World is available for pre-order now. Find out more about Brit and her work here: Instagram : @britfinucci https://niwa.co.nz/people/brit-finucci-0 https://saveourseas.com/project-leader/brittany-finucci/ Follow us on social media! We are @saveourseasfoundation across all platforms.

From a shovel to a mallet, and even an aeroplane - the hammerheads really do win the prize for some of the most bizarrely shaped sharks out there. But why do they have such oddly-shaped noggins? What do they eat? Where do we find them? And why are one of the most charismatic groups of sharks in the world also one of the most threatened? In this episode we are joined by Dr Kelly Kingon, Associate Professor at the University of the Bahamas, SOSF project leader and co-director of the non-profit CHaPO (Conserve Habitats and Protect Organisms). Kelly has been trying to find scalloped hammerhead nurseries in Trinidad and Tobago to inform conservation and management strategies for this heavily fished species. We discuss the amazingness of hammerheads, their unique adaptations and conservation status, before zooming in on Kelly's research to discover what's happening to baby hammers in the warm waters of the Carribean. Shownotes: www.saveourseas.com/worldofsharks/podcast Find out more about Kelly's work: https://saveourseas.com/project/community-supported-conservation-goals-for-scalloped-hammerhead/ https://www.facebook.com/iCHaPO.TT/ https://www.linkedin.com/company/ichapo/ Instagram: ichapo_tt TikTok: chapo_tt ichapo.com FREEthelab.com Find out more about us: www.saveourseas.com @saveourseasfoundation

Tagging hammerheads, tracking silky sharks and exploring a remote coral paradise in the middle of the Gulf of Mexico…This week, we’re diving into the fascinating world of shark trophic ecology with PhD researcher and SOSF project leader Brett Sweezey! Brett is investigating the interactions between predators and prey, and how they influence where sharks go amongst the unique habitats of the Flower Garden Banks National Marine Sanctuary. Join us as we discuss the innovative methods Brett is using, some fascinating early findings, and the challenges and triumphs of studying these incredible creatures in their natural habitat. You can follow Brett across all platforms: @saltwatersweezey. You can also find out more about his project here: https://saveourseas.com/project/methods-to-reduce-shark-stress/ Shownotes: www.saveourseas.com/worldofsharks/podcast

A turtle that looks like a pig, and a shark that looks like a plane...in this episode, we're heading to the colourful, diverse lands of the Kikori River in Southern Papua New Guinea to meet researcher and director of the Piku Biodiversity Network ( www.pikubionet.org.pg ). In 2018, Yolarnie expanded the PBN - which originally focussed on the community-led conservation of the endangered pig-nosed turtle - to include the 45 species of shark and ray that can be found in the Kikori river system. These species include the unusual and understudied winghead shark, one of the few sharks that passes between salt and freshwater to give birth to its young. Find out more about Yolarnie's project, which she co-leads with Dr Michael Grant, here: https://saveourseas.com/project-leader/yolarnie-amepou/ Shownotes: www.saveourseas.com/worldofsharks/podcast

Dive into the deep, remote waters of New Zealand's Fiordland with us as we meet the mysterious broadnose sevengill shark and the scientist who is trying to study them: Dr Alice Rogers. Alice's research aims to discover how these ancient creatures are responding to climate change - will the fiords provide vital refuge for the species as our waters get warmer?Along the way, she and her team are uncovering uncovering the secrets of these elusive "grandpa" sharks. Shownotes: www.saveourseas.com/worldofsharks/podcast Follow Alice: @dralicerogers Find out more: https://saveourseas.com/project/climate-change-at-the-end-of-the-earth-sevengill-sharks-in-fiordland-new-zealand/ https://www.southernfiordland.nz