Colin Simpfendorfer
@sharkcolin.bsky.social
Shark scientist since 1986. Passionate about sharks and rays, and their conservation and management. Lapsed academic.
Recent Grads! We are hiring six Fish Biologist-Survey positions across multiple duty stations. Applications are due by April 20, 2026. For more detailed information on responsibilities and how to apply: www.fisheries.noaa.gov/careers-more...
In Issue 13, get the latest on our IUCN Red List assessments: what we’ve covered so far and where we’re heading next to strengthen the global picture for sharks, rays, and chimaeras. Read issue 13 here: www.iucnssg.org/shark-news.h... Or view online: 784f07501.flowpaper.com/IUCNSSCSSGSh...
The sandbar shark is so boring even the triangles it forms with its fins are obtuse. #YawnShark @whysharksmatter.bsky.social
New paper is out 🔓! We reconstructed the 145-myr diversity of sharks & rays using deep learning, unveiling hidden patterns: - modern diversity levels by the Cretaceous 📈 - small decline in the K/Pg 🤏 - a peak in the Eocene 🌄 - a long-term decline towards the present � www.cell.com/current-biol...
New online! Bending back the curve of shark and ray biodiversity loss
Bending back the curve of shark and ray biodiversity loss
Nature Reviews Biodiversity, Published online: 22 January 2026; doi:10.1038/s44358-025-00120-2Global shark and ray populations have declined sharply, driven by expanding fisheries and inequitable gaps in catch, trade and distribution data. This Review assesses global status, highlights drivers of decline, and outlines the regulatory, market-based and conservation actions needed to reduce mortality and reverse shark and ray biodiversity loss.
dlvr.it
Great 🧵on 🦈 trends by @nickdulvy.bsky.social 👇🏼
Nick Dulvy@nickdulvy.bsky.social · 7mo agoNew paper out today in @natrevbiodiv.nature.com by the #GlobalSharkTrends team: Bending back the curve of shark & ray biodiversity loss; Read the paper here: rdcu.be/eZ9n9 @sfu.ca @sfubiosciences.bsky.social @earth2ocean.bsky.social
We don’t need new frameworks — we need to connect and implement the ones we have. Fisheries management, trade rules, compliance, and demand must align to reduce fishing mortality at scale. Implementation is the bottleneck. @hollieboothie.bsky.social @sharkcolin.bsky.social
Decline is not inevitable. Where fishing mortality has been reduced — through catch limits, retention bans, or spatial protection — shark and ray populations are stabilizing or recovering. Recoveries documented for wide-ranging and restricted-range species @charlie-huveneers.bsky.social
Gaps in catch limits, compliance, and enforcement mean fishing mortality stays high even where policies exist. Where management is complete, risk is lower and recovery is possible. @hollieboothie.bsky.social @sharkcolin.bsky.social Read the paper here: rdcu.be/eZ9n9
Overfishing is compounded by under-management Fishing mortality is the primary driver & management completeness (for guitarfishes & requiem sharks) stands at ~49% globally. @sammsherman27.bsky.social @vanderwright.bsky.social Read the paper here: rdcu.be/eZ9n9
What’s driving the decline? The crisis isn’t just fishing — it’s invisible fishing. Much shark & ray catch is under-reported, aggregated, or mislabeled, masking real mortality & delaying management. What we don’t measure, we don’t manage. @cgmull.bsky.social @nathanpacoureau.bsky.social
Sharks & rays are sentinels of ocean health. - Global abundance has been fished down by 65%, - Now 37.5% of species are threatened, - The current extinction rate is 25–250 times greater than the background fossil record, with greatest losses in tropical coastal seas. #BiodiversityTargets
New paper out today in @natrevbiodiv.nature.com by the #GlobalSharkTrends team: Bending back the curve of shark & ray biodiversity loss; Read the paper here: rdcu.be/eZ9n9 @sfu.ca @sfubiosciences.bsky.social @earth2ocean.bsky.social
Sometimes you stumble on some #sharkscience that makes you think you don't really know anything about them at all. Yesterday i found this paper: "Observations of the bowmouth guitarfish by-catches by the tropical tuna purse seine fleet in the Indian Ocean’s open waters" doi.org/10.1017/S002...
And more new #sharkscience, this time from Sushmita Mukherji "Assessing mechanisms of intrinsic vulnerability in sharks occupying different marine environments" link.springer.com/article/10.1... @imas-utas.bsky.social @iucnshark.bsky.social
Assessing mechanisms of intrinsic vulnerability in sharks occupying different marine environments - Biodiversity and Conservation
The status of many shark species worldwide is concerning due to a combination of their life-history traits and widespread exposure to threats, especially fishing. However, the intrinsic vulnerability ...
link.springer.com
New #sharkscience #sharkconservation "Bending back the curve of shark and ray biodiversity loss" in @natrevbiodiv.nature.com go.nature.com/4jXOnaC What will it take to reverse shark biodiversity loss? Find out in our new article out today. @nickdulvy.bsky.social @iucnshark.bsky.social
Bending back the curve of shark and ray biodiversity loss - Nature Reviews Biodiversity
Global shark and ray populations have declined sharply, driven by expanding fisheries and inequitable gaps in catch, trade and distribution data. This Review assesses global status, highlights drivers...
aus01.safelinks.protection.outlook.com
🐟 New vacancy in the fish tracking community 📢 Come join Dr. Jan Reubens and his team at the Flanders Marine Institute (@vliz.be) as a Fish Behavioral Ecology Researcher! 🔗Read more about the position and apply here: www.vliz.be/en/jobs/vliz... ❗Deadline 25 January, 2026
VLIZ recruits: Fish Behavioral Ecology Researcher
vliz.be
🚨 Job Alert! TT Assistant Professor of Marine Biology at the University of Alaska Fairbanks! Looking for a candidate with a focus on coastal ecology. Come be my colleague! Please share. careers.alaska.edu/jobs/assista...
The last proposal for sharks has just passed at #CITESCoP20. Gulper Sharks have been adopted into Appendix II of CITES. This marks a major victory for sharks and rays as all proposals have been adopted! #CITES #CoP20 #gulpershark #shark #ray #chimaera #biodiversity #conservation #trade #conference
The 2024–25 IMOS Annual Highlights are now out, showcasing key achievements from across our program and community 🌊 🔗 bit.ly/3MkLMKQ #NCRISImpact
We are hiring: #PhD fellow in Ecosystem-based management and marine connectivity🐋🧪🛰️ Want to work with tracking data from migratory species to identify ecological corridors and help inform biodiversity conservation priorities? Apply by Dec 7th! @bioprotectproject.bsky.social tinyurl.com/ytfmfhfc
PhD Fellow in Ecology/Ecosystem-Based Management (289259) | UiT The Arctic University of Norway
Job title: PhD Fellow in Ecology/Ecosystem-Based Management (289259), Employer: UiT The Arctic University of Norway, Deadline: Sunday, December 7, 2025
jobbnorge.no
A guide to: Sri Lankan Wildlife 🐆 Sri Lanka is a global biodiversity hotspot, home to unique and endemic species, including around 140 mammals, 400 birds, and 170 reptiles. 🦈 SI2026 📅 Dates: 4-8 May 📍 Location: Colombo, Sri Lanka 🔗 si2026.org
It's live! Impacts of Deep-sea Mining on Migratory Species: Review and Knowledge Gaps. In English, French, and Spanish. Annex I is the actual report. www.cms.int/document/dee...
25.2.3 Deep-Sea Mining | Convention on the Conservation of Migratory Species of Wild Animals
cms.int
📣 Announcement! Abstract Submission Deadline Extended to November 30, 2025 Being guilty of last minute submissions ourselves, we felt that a few more days would help those of you processing your abstract ideas! 👉 si2026.org
Seven JCU researchers have been named in the @clarivateag.bsky.social annual list of Highly Cited Researchers. Demonstrating significant and broad influence in their fields of research. See the full list here: clarivate.com/highly-cited...
Clarivate Highly Cited Researchers 2025
The Highly Cited Researchers 2025 list identifies and celebrates individuals who have demonstrated significant and broad influence in their fields of research. Through rigorous selection criteria and ...
clarivate.com
NEW #SharkLeague #ICCAT Factsheet outlines key steps needed to strengthen existing measures & close critical gaps - from enforcing the finning ban & rebuilding shortfin mako populations to protecting basking & white sharks, & ensuring sustainable blue 🦈 fisheries sharkleague.org/2025/11/10/i...
ICCAT 2025: Shark League Calls for Stronger Protections
The Shark League’s ICCAT 2025 factsheet outlines science-based steps to protect sharks and rays and strengthen Atlantic conservation.
sharkleague.org
PhD position - Changing Ecological Role of Coral Reef Marine Protected Areas. One of the new @exageo-dla.bsky.social advertised projects: www.exageo.org/phd-student-... - deadline for applications 9th January. International applications welcome. Come and join us @lec-reefs.bsky.social
Annual plug for the fabulous phylopic.org website with tens of thousands of easily searchable silhouette images for almost every life form imaginable. They make nice additions to your biology plots!
For the past 4 years I have worked with a wonderful team of scientists and anglers to track sharks in recreational fisheries. With close to 70 tags deployed, we found that good angling practice can result in pretty high survival for sharks! 🦈🎣🌊
Exeter Marine@exetermarine.bsky.social · 9mo agoNEW PAPER: Survival and recovery of three shark species in North-East Atlantic recreational fisheries. academic.oup.com/icesjms/arti... @garzonfrancesco.bsky.social @drmjwitt.bsky.social 🦑🐟🧪🌐🌊🎣