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.