Wade VanderWright

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...

What success looks like (5–10 years)
• Fishing mortality aligned with species’ life histories
• Species-level reporting becomes the norm
• Management completeness rises above critical thresholds
• Shark & ray populations stabilize and recover

Read the paper here: rdcu.be/eZ9n9

• 40% of global shark & ray catch comes from low- and middle-income countries
• Small-scale fisheries underpin livelihoods and food security
• Under-resourced management = high biodiversity & social risk
• Reduced fishing mortality reduces extinction & social risk, improving ecosystem functions.

Bending back the biodiversity loss curve of sharks and rays. The loss of sharks and rays to date has involved serial depletion of the largest, most evolutionary and functionally distinct species, and the increasing prevalence of smaller-bodied species that have benefited from release from predation.

Where investment has the highest leverage to bend back biodiversity loss?

Funding that strengthens:
• Species-level catch & trade data
• Compliance and enforcement
• Capacity in national agencies
• Monitoring in small-scale fisheries
→ Directly reduces fishing mortality

A theory of shark and ray conservation change. Structural drivers of shark and ray decline can be addressed through three types of measures that target trade and demand management, fisheries management, and rehabilitation.

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

Green List Status Assessment of the Banded Wobbegong (Orectolobus halei) The recovered (blue) status compared to what the past status might have been without conservation (Conservation Legacy, green) and future status unless management continues (Conservation Dependency, orange).

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

Progress and priorities in shark and ray fisheries management. The risk to species owing to incomplete management (‘M-Risk’, part a) can be described by Compliance, one of 19 attributes across four classes for requiem sharks and guitarfishes

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

Progress and priorities in shark and ray fisheries management. The risk to species owing to incomplete management (‘M-Risk’, part a) can be described by 19 attributes across four classes for requiem sharks and guitarfishes.

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

Taxonomic differentiation of catch. FAO (United Nations Food and Agricultural Organization) on the percentage of catch reported to the species level worldwide.

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

Extinction risk and the spatial patterning of shark, ray and chimaera richness, including hotspots of coastal and deepwater richness, for wide-ranging and endemic species.

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

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...

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 biodiversity loss curve of sharks and rays. The loss of sharks and rays to date has involved serial depletion of the largest, most evolutionary and functionally distinct species, and the increasing prevalence of smaller-bodied species that have benefited from release from predation.

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

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.

New online! Bending back the curve of shark and ray biodiversity loss

Why Vancouver's decision to host a Harry Potter attraction quickly became controversial | CBC News It's a story bringing together two very different things that nonetheless regularly attract controversy: the Vancouver Park Board and the Harry Potter universe.

Bravo @cbcstephenquinn.bsky.social for taking Vancouver Park Board to task for this terrible decision.

🚂 Back up this train, folks! 🚂

* JK Rowling fuels hatred and financially benefits from this deal
* U.S. based company delivers it

www.cbc.ca/news/canada/...

Image credit: April Bencze

The last 10 yrs were the worst decade on record for salmon spawner monitoring in Pacific Canada. Any scientist who works with local-scale salmon abundance data knows this. Many papers written about the 'ghost streams' no longer monitored by the streamwalkers of decades past. We wrote another.

The next wave of monitoring cuts crests. Brutal. How do you steward salmon without counting them? You don't.

I am close to this issue & I know nuance abounds but I don't see how hundreds of millions of dollars towards restoration work can be effective without counting the fish we seek to support.

Opinion: It's time to fast-track actions to defend B.C.'s lands, waters, fish and wildlife B.C. recently passed Bills 14 and 15. As a scientist who studies the health of western Canada’s ecosystems, my alarm bells are going off

Published an op-ed the other day--fast-tracking actions to protect lands, waters, fish, and wildlife.

BC and Canadian policies are rushing natural resource extraction forward--there is a parallel need to fast-track safeguards of lands and waters.
vancouversun.com/opinion/op-e...

@fao.org released their 2025 report on the status of marine fisheries resources (openknowledge.fao.org/items/ac6d51...).
In talking to the media about the report at #UNOC FAO stated that ~57% of sharks stocks are sustainably fished (t.co/fVFnZkY4vQ).
This fact is WRONG
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Professional fishers’ knowledge informs distribution and interaction dynamics of Sawfish and River Sharks in coastal fishing grounds of the Northern Territory, Australia - Maritime Studies Through their time at sea professional fishers possess and obtain invaluable knowledge and insights into the behaviour, distribution, and abundance of both target and non-target species. Their observa...

New #sharkscience led by Vinay Udyawer
Professional fishers’ knowledge informs distribution and interaction dynamics of Sawfish and River Sharks in coastal fishing grounds...

Amazing insights from fisher interviews about their changing interactions through time
link.springer.com/article/10.1...

‘Gut punch’: top shark expert quits Queensland advisory panel after LNP expands cull program Exclusive: Colin Simpfendorfer’s resignation comes as other members of working group members say state government went against their advice against expanding lethal controls

Colin Simpfendorfer’s resignation from working group comes as conservationists lash expansion of lethal program they say ‘does nothing to improve beach safety’
www.theguardian.com/australia-ne...

I've waited a decade to finally have the chance to work with this ghost #shark 👻🦈 legend. While we were geeking away on this giant beast, we also got word that the first and only Ghost Sharks of the World book finally has a released date. Coming to you January 2026!

The carbon tax in Canada, explained | The Narwhal Canada’s carbon tax is on thin ice. We explain the consumer vs. industrial price and what Poilievre, Carney are saying amid the federal election

The rise and fall of the carbon tax, explained by @thenarwhal.ca
thenarwhal.ca/video-carbon...

Just 8 of 422 species at risk of extinction are doing better: study | The Narwhal A new study found a crucial first step to recover endangered species, is to stop the harm

From peregrine falcons to humpback whales, a new study finds a crucial first step to recover an endangered species is to stop known harms.
via @ainsliecruickshank.bsky.social thenarwhal.ca/endangered-s...

Welcome to the Salmon Watersheds Lab! We are a group of fishy folks doing aquatic ecology research @ Simon Fraser University! 📚🤓🐟 Led by our fearless fish leader, Dr. Jonathan Moore. Follow along for lab updates, opportunities, and some good ol’ fish content! #salmon #AquaticEcology

Just 8 of 422 species at risk of extinction are doing better: study | The Narwhal A new study found a crucial first step to recover endangered species, is to stop the harm

A handful of Canada’s at-risk species have made a comeback. Here’s what they can teach us | @thenarwhal.ca
thenarwhal.ca/endangered-s...

#SARA #COSEWIC #Conservation

A reminder that there is a starter pack for the CONSERVATION PHYSIOLOGY COMMUNITY. Today we welcomed cons phys gurus @trishschulte.bsky.social @physiologyfish.bsky.social & @craigefranklin.bsky.social. Ping me if you work in this space and want to be added! go.bsky.app/RRAUWkk

New summary of 2 massive recent publications documenting the status and trends of sharks, rays, and chimaeras 🧪🦈🌎 @mongabay.bsky.social
news.mongabay.com/2025/01/new-...

🚨New postdoc positions available: we are looking for 2 postdoctoral researchers to join a large, collaborative effort to document, describe, and investigate the biodiversity of tiny, cryptobenthic fishes in the Indo-Pacific 🤏🐠🧪. More details: fishandfunctions.com/join%F0%9F%9...

Please repost 🦑🧪

🦈🌎🦞🧪https://www.sfu.ca/sfunews/stories/2024/12/new-study-finds-overfishing-has-halved-shark-and-ray-populations.html

Dive into the exciting work of the Earth to Ocean Research Group! Follow our brilliant students, research assistants, lab managers, postdocs, and faculty as they explore, discover, and make waves in science. 🌊✨

go.bsky.app/153jnvd

Nouvelle étude #GlobalSharkTrends publiée dans @ScienceMagazine révèle que la #surpêche a réduit de 50% les populations de requins et de raies en 50 ans, causant une érosion des fonctions écologiques et un risque d'extinction élevé.
Article : bit.ly/GlobalSharkT...
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