River sharks and rays make up an entire category of animal that's fallen through the gap between ocean and freshwater conservation. While great whites, tiger sharks, and manta rays draw research funding and public attention, roughly 60 species of sharks and rays that depend on rivers, estuaries, and other inland waters worldwide have gone largely unassessed, and an estimated 75% of non-marine sharks and rays in the Indo-Pacific region are considered threatened with extinction [VERIFY: figures from secondary coverage of a Mongabay story, not the primary article, see Flags section].
On this episode of Ocean Decoded Live, Andrew Lewin explains why "flat sharks", the rays, skates, guitarfish, and wedgefish that don't look like the sharks most people picture, are sharks too, and walks through a real example: a Charles Darwin University expedition led by PhD candidate Julia Constance and Senior Research Fellow Dr. Peter Kyne that confirmed a breeding population of the Speartooth Shark in the Roper River, Northern Territory, Australia.
The threats are concrete. A single dammed river or a cleared mangrove stand can wipe out an entire population of a species with narrow, specific habitat needs, sometimes before scientists have even finished documenting its basic biology. Andrew also highlights the ongoing work of researchers like Patricia Charvet, who studies freshwater stingrays in Brazil, and closes with a call to support conservation organizations and campaigns that explicitly include freshwater and estuarine species.
Chapters:
0:00 – Cold Open: Freshwater and Estuarine Sharks and Rays
3:05 – Meet Julia Constance and Dr. Peter Kyne
6:29 – Why Studying These Species Helps Protect All Sharks
9:36 – How Much We Still Don't Know About Sharks
12:49 – Final Sign-Off: Andrew Lewin, Happy Conservation
Takeaways:
Roughly 60 species of sharks and rays depend on rivers, estuaries, and other inland waters worldwide.
An estimated 75% of non-marine sharks and rays in the Indo-Pacific region are considered threatened with extinction, a rate described as running close to double that of marine species.
Habitat destruction, especially mangrove clearing for shrimp farming, plus general river and estuarine pollution, are the named drivers.
A Charles Darwin University expedition led by Julia Constance and Dr. Peter Kyne confirmed a breeding population of the Speartooth Shark in the Roper River, Northern Territory, Australia.
"Flat sharks," rays, skates, guitarfish, and wedgefish, are sharks too, and belong in the same conservation conversation as great whites and tiger sharks.
If you support shark and ray conservation, check whether the organizations and campaigns you follow include freshwater and estuarine species. Most don't yet.
Ocean Decoded Live streams Monday through Thursday, 4:00–6:00 PM Eastern, hosted by Andrew Lewin. Subscribe and hit the bell so you don't miss it.
#OceanConservation #MarineBiology #SaveOurOceans #ProtectTheOcean #OceanAwareness #BluePlanet #ConservationMatters #ScienceForChange #SustainableOceans
--------------------------------------------------------------------------------------------------------------------------------------------
Follow a career in conservation: https://www.conservation-careers.com/online-training/ Use the code SUFB to get 33% off courses and the careers program.
Do you want to join my Ocean Community?
Sign Up for Updates on the process: www.speakupforblue.com/oceanapp
Sign up for our Newsletter: http://www.speakupforblue.com/newsletter
Facebook Group: https://bit.ly/3NmYvsI
Connect with Speak Up For Blue:
Website: https://bit.ly/3fOF3Wf
Instagram: https://bit.ly/3rIaJSG
TikTok: https://www.tiktok.com/@speakupforblue
Twitter: https://bit.ly/3rHZxpc
YouTube: www.speakupforblue.com/youtube
