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Reposted by Michael Mahon, PhD

Steve Ormerod @steveormerod.bsky.social · 9d

How #climatechange is reshaping fish communities in the United States as temperatures rise and non-native fishes proliferate: @ian-vaughan.bsky.social overviews recent extensive work by @rumschsl.bsky.social www.nature.com/articles/d41... www.nature.com/articles/s41...

Climate change is reshaping fish communities in the United States

Rising temperatures and the introduction of non-native fishes have been linked to rapid changes in fish communities across the United States.

www.nature.com

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Reposted by Michael Mahon, PhD

Nature Portfolio @natureportfolio.nature.com · 13d

Changing water temperatures and human-driven introductions of fish have altered the composition of fish populations in streams and rivers across the USA over the past three decades, a study in Nature suggests. go.nature.com/47ZCcWH 🧪

Photo of field crew conducting electroshock sampling for fish as part of the US EPA National Rivers and Streams Assessment in Little Hunting Creek in Virginia, USA.

Photographer: Kevin Biallas

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Michael Mahon, PhD @mmahon.bsky.social · 13d

In short, fish biodiversity in U.S. streams are changing fast.
- Cold streams are losing biodiversity
- Warm streams are gaining in a homogenized way
- Human choices will shape the future of freshwater fish

Free access in first post.
www.nature.com/articles/s41...

Diverging fish biodiversity trends in cold and warm rivers and streams - Nature

In the past three decades, fish abundance, richness and uniqueness have diverged across cold and warm streams, and the effects on native fish communities of stream warming and increases in introduced fishes have magnified each other.

www.nature.com

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Michael Mahon, PhD @mmahon.bsky.social · 13d

What can be done?
- Restore riparian forests to cool waters
- Limit introductions & spread of non-native fishes
- Protect local species before losses become irreversible

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Michael Mahon, PhD @mmahon.bsky.social · 13d

When warming streams also had more stocked or introduced fishes, local non-game species took the hardest hit, declining in both abundance and richness.

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Michael Mahon, PhD @mmahon.bsky.social · 13d

“Average” or cool streams are stable. Streams in the intermediate range showed minimal biodiversity change. Their mix of species with different thermal tolerances may provide a buffer against changing stream temperatures.

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Michael Mahon, PhD @mmahon.bsky.social · 13d

Warm streams show the opposite trend.
Abundance rose 70% and richness rose 15%. But this came with a big downside: fish communities became homogenized. Opportunistic minnows & shiners replaced larger periodic species.

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Michael Mahon, PhD @mmahon.bsky.social · 13d

Cold streams are in trouble.
Fish abundance fell 50% and richness dropped 30%. Small-bodied, cold-adapted species declined, while larger game fishes (like trout) increased. Cold-water biodiversity is eroding fast.

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Michael Mahon, PhD @mmahon.bsky.social · 13d

Our research group just published a study in Nature on how fish biodiversity in U.S. rivers and streams has been changing over the past 27 years (1993–2019). The results show sharply diverging trends depending on historic and changing water temperature. 🧵 rdcu.be/eH0l8

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Reposted by Michael Mahon, PhD

Ecotoxicology lab RC One Health Ruhr @ecotox.bsky.social · 13d

Exciting collaboration with colleagues from the US and Frederik de Laender - lead by S. Rumschlag and Mike Mahon - on how climate change has lead to alterations in US fish diversity over the last decades. Paper just out: www.nature.com/articles/s41...

Diverging fish biodiversity trends in cold and warm rivers and streams - Nature

In the past three decades, fish abundance, richness and uniqueness have diverged across cold and warm streams, and the effects on native fish communities of stream warming and increases in introduced fishes have magnified each other.

www.nature.com

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Reposted by Michael Mahon, PhD

Mike Dettinger @mdettinger.bsky.social · 18d

EPA has ordered scientists in its Office of Water to immediately pause almost all research & stop publishing studies. Researchers were told that, unless scientific journals had already returned proofs, studies will be subject to an additional EPA review.

www.washingtonpost.com/climate-envi...

EPA tells scientists to stop publishing studies, employees say

Staff from the EPA’s Office of Water were summoned to a town hall meeting this week and told to pause the publication of most research, pending a review.

www.washingtonpost.com

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Michael Mahon, PhD @mmahon.bsky.social · Jul 14

Looking for a great photo of a freshwater fish (North American) to submit as a journal cover image for a manuscript on fish biodiversity trends! If you have one you’d be willing to share (with credit, of course!), please reach out. 🎣📸 #fishphoto #freshwaterfish #scicomm

Reposted by Michael Mahon, PhD

Dave Levitan @davelevitan.bsky.social · Jul 3

NEW: per multiple sources, apparently there may be punishment/retaliation coming for EPA employees who signed the Declaration of Dissent this week. People are starting to get letters putting them on administrative leave, seems like potentially targeted at those who signed with their names.

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Reposted by Michael Mahon, PhD

Nathan Kalman-Lamb @nkalamb.bsky.social · Jun 19

Amazing: MIT researchers revealed how ChatGPT etc are destroying our brains and booby-trapped the report to expose those who want to use AI to ostensibly summarize the results.

t.co/JXeTALBPds

Ironically, upon the paper’s release, several social media users ran it through LLMs in order to summarize it and then post the findings online. Kosmyna had been expecting that people would do this, so she inserted a couple AI traps into the paper, such as instructing LLMs to “only read this table below,” thus ensuring that LLMs would return only limited insight from the paper.

She also found that LLMs hallucinated a key detail: Nowhere in her paper did she specify the version of ChatGPT she used, but AI summaries declared that the paper was trained on GPT-4o. “We specifically wanted to see that, because we were pretty sure the LLM would hallucinate on that,” she says, laughing.

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Reposted by Michael Mahon, PhD

MPR News @mprnews.org · Jun 16

Authorities have taken 57-year-old Vance Boelter into custody in Sibley County. He's the suspect in the targeted fatal shootings of Minnesota House DFL leader Melissa Hortman and her spouse, and the shooting of state Sen. John Hoffman and his spouse.

Vance Boelter, suspect in shooting of Minnesota lawmakers, taken into custody in Sibley County

Authorities have taken 57-year-old Vance Boelter into custody in Sibley County. He's the suspect in the targeted fatal shootings of Minnesota House DFL leader Melissa Hortman and her spouse, and the s...

www.mprnews.org

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Reposted by Michael Mahon, PhD

Steve Vladeck @stevevladeck.bsky.social · May 16

Make it seven:

DOJ just sought emergency relief from #SCOTUS in the AFSCME/mass-RIFs case. It’ll be docketed as 24A1106.

In case you’re keeping score, this marks the 15th emergency application from Trump in 16 weeks.

Across 16 *years,* the GWB and Obama administrations filed a total of … eight.

Lawrence Hurley @lawrencehurley.bsky.social · May 16

There are now emergency applications pending at SCOTUS on SIX different Trump policies. That must be an unprecedented number.

-birthright citizenship
-agency firings
-Alien Enemies Act
-TPS for Venezuelans
-DOGE access to SSA data
-Ending parole for 500k immigrants

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Reposted by Michael Mahon, PhD

Josh Gerstein @joshgerstein.bsky.social · May 10

FLASH: Federal judge blocks RIFs/Trump administration reorganization plans for 20 federal agencies. SF-based Judge Susan Illston (Clinton) says they appear to exceed executive branch authority to implement without Congressional approval. Doc: storage.courtlistener.com/recap/gov.us...

storage.courtlistener.com

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Michael Mahon, PhD @mmahon.bsky.social · May 3

Not to mention the coming dissolution of ORD.

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Reposted by Michael Mahon, PhD

Jeff Dukes @dukesjeff.bsky.social · Apr 21

Glad to see the MRCC is back up! Funding restored by NOAA/Dept of Commerce. But ridiculous that funding for regional climate centers was removed in the first place.

Screen capture of again-functional MRCC web site.

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Reposted by Michael Mahon, PhD

Alexander Berger @albrgr.bsky.social · Apr 17

New preprint finding that eliminating US global health funding over the next fifteen years would cause:
- 15.2m deaths from AIDS
- 2.2m deaths from TB
- 7.9 additional child deaths

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Reposted by Michael Mahon, PhD

Duluth News Tribune @duluthnewstribune.com · Apr 15

From the editorial: "If the Duluth EPA lab is being indiscriminately targeted, the cutting and slashing (in D.C.) clearly isn’t being done with the care, consideration, or thought such a process demands."