Dr. Catherine Macdonald
@drcatmac.bsky.social
Marine scientist and teacher Field School & University of Miami. Director of sharktagging. NatGeo Explorer. Shark & ray ecology, biology, conservation. She/her.
Reposted by Dr. Catherine Macdonald
January 19, 2026 at 10:25 AM
Reposted by Dr. Catherine Macdonald
The secret lives of #Florida’s elusive, giant manta rays www.sun-sentinel.com/2026/01/17/t... via @jenstaletovich.bsky.social
The secret lives of Florida’s elusive, giant manta rays
New findings reveal how South Florida’s waters are nursery grounds for the mysterious giant rays, and how mantas function as mobile homes to many other species.
www.sun-sentinel.com
January 18, 2026 at 8:18 PM
The secret lives of #Florida’s elusive, giant manta rays www.sun-sentinel.com/2026/01/17/t... via @jenstaletovich.bsky.social
Reposted by Dr. Catherine Macdonald
High Seas Treaty #BBNJ enters into force tomorrow, marking a new era for ocean governance and migratory species that depend on connected high seas habitats.
CMS stands ready to help conservation measures beyond national borders deliver real benefits for marine wildlife: www.cms.int/news/high-se...
CMS stands ready to help conservation measures beyond national borders deliver real benefits for marine wildlife: www.cms.int/news/high-se...
January 16, 2026 at 3:19 PM
High Seas Treaty #BBNJ enters into force tomorrow, marking a new era for ocean governance and migratory species that depend on connected high seas habitats.
CMS stands ready to help conservation measures beyond national borders deliver real benefits for marine wildlife: www.cms.int/news/high-se...
CMS stands ready to help conservation measures beyond national borders deliver real benefits for marine wildlife: www.cms.int/news/high-se...
Reposted by Dr. Catherine Macdonald
Well shoot isn’t that a cute snoot on the eagle ray with some serious barbs to boot! #spottedeagleray #eagleray #stingraysofcoralcity #stingray #cutesnoot #venomousfish #elasmobranch #coral #coralcitycamera #miami #portmiami #biscaynebay #coralcity
January 16, 2026 at 4:31 PM
Well shoot isn’t that a cute snoot on the eagle ray with some serious barbs to boot! #spottedeagleray #eagleray #stingraysofcoralcity #stingray #cutesnoot #venomousfish #elasmobranch #coral #coralcitycamera #miami #portmiami #biscaynebay #coralcity
Reposted by Dr. Catherine Macdonald
Analysis of video from #freediving shows that #mantarays near #Florida may function as a mobile ecosystem.
Example:
Juvenile fish moving between reefs might do better traveling with Manta been moving alone along a Sandy bottom.
Example:
Juvenile fish moving between reefs might do better traveling with Manta been moving alone along a Sandy bottom.
Catch amazing PhD candidate Emily Yeager @emilyyeager9.bsky.social on public radio talking about her recent publication!
The secret lives of Florida's elusive, giant manta rays
According to a new study and hundreds of videos shot mostly in waters near Palm Beach County, manta rays can act as a mobile home, providing food, shelter, even honeymoon suites for fish in sometimes ...
www.wlrn.org
January 15, 2026 at 1:30 PM
Analysis of video from #freediving shows that #mantarays near #Florida may function as a mobile ecosystem.
Example:
Juvenile fish moving between reefs might do better traveling with Manta been moving alone along a Sandy bottom.
Example:
Juvenile fish moving between reefs might do better traveling with Manta been moving alone along a Sandy bottom.
Catch amazing PhD candidate Emily Yeager @emilyyeager9.bsky.social on public radio talking about her recent publication!
The secret lives of Florida's elusive, giant manta rays
According to a new study and hundreds of videos shot mostly in waters near Palm Beach County, manta rays can act as a mobile home, providing food, shelter, even honeymoon suites for fish in sometimes ...
www.wlrn.org
January 15, 2026 at 12:41 PM
Catch amazing PhD candidate Emily Yeager @emilyyeager9.bsky.social on public radio talking about her recent publication!
Reposted by Dr. Catherine Macdonald
The red dot is a baby North Atlantic right whale trying to migrate up the east coast of the United states.
The blue streaks are fast moving shipping vessels entering and leaving New York City harbor.
One collision and the whale is dead.
We need *mandatory* speed limits for these vessels! 🧪🦑🌍
The blue streaks are fast moving shipping vessels entering and leaving New York City harbor.
One collision and the whale is dead.
We need *mandatory* speed limits for these vessels! 🧪🦑🌍
January 14, 2026 at 4:34 PM
The red dot is a baby North Atlantic right whale trying to migrate up the east coast of the United states.
The blue streaks are fast moving shipping vessels entering and leaving New York City harbor.
One collision and the whale is dead.
We need *mandatory* speed limits for these vessels! 🧪🦑🌍
The blue streaks are fast moving shipping vessels entering and leaving New York City harbor.
One collision and the whale is dead.
We need *mandatory* speed limits for these vessels! 🧪🦑🌍
Reposted by Dr. Catherine Macdonald
"Nope, just this one picture that obscures all the characteristics you need for identification!"
January 14, 2026 at 1:15 PM
"Nope, just this one picture that obscures all the characteristics you need for identification!"
Reposted by Dr. Catherine Macdonald
That was a real low point for marine biogeography research
But a high point for internet mockery
But a high point for internet mockery
January 14, 2026 at 1:01 PM
That was a real low point for marine biogeography research
But a high point for internet mockery
But a high point for internet mockery
Also: we had a situation in shark science where a range-extension paper was retracted because a photo of a child’s toy washed up on a beach confused experts! So assuming we’re all going to be able to discern reality from endless reams of AI slop forever seems pretty optimistic.
January 14, 2026 at 12:57 PM
Also: we had a situation in shark science where a range-extension paper was retracted because a photo of a child’s toy washed up on a beach confused experts! So assuming we’re all going to be able to discern reality from endless reams of AI slop forever seems pretty optimistic.
Reposted by Dr. Catherine Macdonald
Yellow stingrays are our smallest cartilaginous fish in Coral City. They are also the most fashionably dressed. 😎 #yellowstingray #stingraysofcoralcity #stingray #elasmobranch #coral #coralhead #coralcitycamera #miami #portmiami #biscaynebay #coralcity
January 13, 2026 at 4:16 PM
Yellow stingrays are our smallest cartilaginous fish in Coral City. They are also the most fashionably dressed. 😎 #yellowstingray #stingraysofcoralcity #stingray #elasmobranch #coral #coralhead #coralcitycamera #miami #portmiami #biscaynebay #coralcity
Reposted by Dr. Catherine Macdonald
“We cannot withdraw from the fact that over 1 million species of plants and animals face extinction.”
IPBES remains committed to its mandate to provide the most credible science and evidence about biodiversity to all decision makers and actors.
— @davidobura.bsky.social , @ipbes.net Chair
IPBES remains committed to its mandate to provide the most credible science and evidence about biodiversity to all decision makers and actors.
— @davidobura.bsky.social , @ipbes.net Chair
January 8, 2026 at 6:13 PM
“We cannot withdraw from the fact that over 1 million species of plants and animals face extinction.”
IPBES remains committed to its mandate to provide the most credible science and evidence about biodiversity to all decision makers and actors.
— @davidobura.bsky.social , @ipbes.net Chair
IPBES remains committed to its mandate to provide the most credible science and evidence about biodiversity to all decision makers and actors.
— @davidobura.bsky.social , @ipbes.net Chair
Reposted by Dr. Catherine Macdonald
ICYMI:
Our new (in December) paper offers advice for early career scientists who want their research to help influence conservation and management policy. Lots of people say that they want to do this, but lack the policy training to do it meaningfully and usefully. Our paper can help!
🧪🦑🌍🦈
Our new (in December) paper offers advice for early career scientists who want their research to help influence conservation and management policy. Lots of people say that they want to do this, but lack the policy training to do it meaningfully and usefully. Our paper can help!
🧪🦑🌍🦈
Shark scientists want their research to help save threatened species, but don’t know how. Our new paper can help.
Sharks are some of the most threatened animals on Earth, and accordingly many scientists who study sharks want their research to be useful for conservation. However, most scientific training does n…
www.southernfriedscience.com
January 8, 2026 at 2:02 PM
ICYMI:
Our new (in December) paper offers advice for early career scientists who want their research to help influence conservation and management policy. Lots of people say that they want to do this, but lack the policy training to do it meaningfully and usefully. Our paper can help!
🧪🦑🌍🦈
Our new (in December) paper offers advice for early career scientists who want their research to help influence conservation and management policy. Lots of people say that they want to do this, but lack the policy training to do it meaningfully and usefully. Our paper can help!
🧪🦑🌍🦈
The best time to get your flu shot was fall, but the second best time is now! 🧪
This year’s flu season just surpassed a grim new record.
Nearly 1 in 10 doctor visits in late December were for flu-like symptoms—the highest level recorded in nearly 30 years. To date, the U.S. has seen 120,000+ hospitalizations and 5,000 deaths, including children. bit.ly/3LkZiOI
Nearly 1 in 10 doctor visits in late December were for flu-like symptoms—the highest level recorded in nearly 30 years. To date, the U.S. has seen 120,000+ hospitalizations and 5,000 deaths, including children. bit.ly/3LkZiOI
January 8, 2026 at 7:01 PM
The best time to get your flu shot was fall, but the second best time is now! 🧪
Reposted by Dr. Catherine Macdonald
Federal govt & boaters fight over rule to protect endangered right whales, which breed off the coast of #Florida every year. www.wgcu.org/environment/... via @wgcunews.bsky.social
Federal government, opponents battle over right whale rule
The federal government is trying to fend off a lawsuit challenging a boat speed limit designed to protect endangered North Atlantic right whales, which migrate each year to calving grounds off Northea...
www.wgcu.org
January 6, 2026 at 10:32 PM
Federal govt & boaters fight over rule to protect endangered right whales, which breed off the coast of #Florida every year. www.wgcu.org/environment/... via @wgcunews.bsky.social
Reposted by Dr. Catherine Macdonald
Jellyfish & sea anemones lack brains & yet seem to sleep in ways similar to humans
New findings bolster a theory that sleep evolved before centralized nervous systems to repair DNA damage that builds up in individual nerve cells while animals are awake.
“Neurons are very precious”
New findings bolster a theory that sleep evolved before centralized nervous systems to repair DNA damage that builds up in individual nerve cells while animals are awake.
“Neurons are very precious”
Jellyfish sleep like humans — even though they don’t have brains
Studying ancient sea creatures’ snoozing habits could shed light on the origins of sleep.
www.nature.com
January 6, 2026 at 10:29 PM
Jellyfish & sea anemones lack brains & yet seem to sleep in ways similar to humans
New findings bolster a theory that sleep evolved before centralized nervous systems to repair DNA damage that builds up in individual nerve cells while animals are awake.
“Neurons are very precious”
New findings bolster a theory that sleep evolved before centralized nervous systems to repair DNA damage that builds up in individual nerve cells while animals are awake.
“Neurons are very precious”
Reposted by Dr. Catherine Macdonald
1. Did you know that Girl Scouts has, for a long time, accepted trans girls and nonbinary scouts?
Trans kids are under attack. Every year, I make a thread of trans and nonbinary girl scouts you can get your cookies from.
Lets get our cookies from them this year in solidarity!
Trans kids are under attack. Every year, I make a thread of trans and nonbinary girl scouts you can get your cookies from.
Lets get our cookies from them this year in solidarity!
2026 Trans Girl Scouts To Order Cookies From!
This year, consider ordering your Girl Scout cookies from a trans girl scout to make their day!
www.erininthemorning.com
January 6, 2026 at 4:16 PM
1. Did you know that Girl Scouts has, for a long time, accepted trans girls and nonbinary scouts?
Trans kids are under attack. Every year, I make a thread of trans and nonbinary girl scouts you can get your cookies from.
Lets get our cookies from them this year in solidarity!
Trans kids are under attack. Every year, I make a thread of trans and nonbinary girl scouts you can get your cookies from.
Lets get our cookies from them this year in solidarity!
The telltale sign is: you are in the ocean.
Sharks are closer than we think. Here are the telltale signs they're nearby
Australia is changing the way it deals with sharks, but can we avoid becoming prey as attacks increase?
www.sbs.com.au
January 5, 2026 at 10:38 PM
The telltale sign is: you are in the ocean.
Come fish with us—the 2025 sections of this class were some of the most fun I had all year!
Friends, I am excited to announce that my Center for Wildlife Studies biology and ecology of sharks course went so well that we're already running it again! Class starts in February and you can sign up now.
🧪🦑🌍🦈
🧪🦑🌍🦈
Biology and Ecology of Sharks and Their Relatives (Online & Field) — Center for Wildlife Studies
www.centerforwildlifestudies.org
January 5, 2026 at 9:05 PM
Come fish with us—the 2025 sections of this class were some of the most fun I had all year!
I’ve never found it tempting to use AI tools in teaching, because I deeply believe that teaching is worth doing as well as I can.
As @jbakcoleman.bsky.social and I wrote, “Every time a scientist abdicates their work to an AI tool, that is a tacit admission that the work is not worth being done by the scientist.”
Same goes for instructors.
Same goes for instructors.
You’ll have to read for the what happens next part, but I can tell you what will happen when parents and students realize profs have handed over expertise and teaching to chatbots.
January 5, 2026 at 8:07 PM
I’ve never found it tempting to use AI tools in teaching, because I deeply believe that teaching is worth doing as well as I can.
Reposted by Dr. Catherine Macdonald
So everyone knows that northern cod collapsed completely in the 1980s and never recovered. Well... it's actually kind of recovering now. Spawning biomass is at pretty good levels, while catches remain at a tiny fraction of the heyday levels.
publications.gc.ca/collections/...
publications.gc.ca/collections/...
January 5, 2026 at 4:54 PM
So everyone knows that northern cod collapsed completely in the 1980s and never recovered. Well... it's actually kind of recovering now. Spawning biomass is at pretty good levels, while catches remain at a tiny fraction of the heyday levels.
publications.gc.ca/collections/...
publications.gc.ca/collections/...
Reposted by Dr. Catherine Macdonald
The deepest confirmed fish observation occurred at ~8,300 m. I know the shape behind it is another fish’s tail, but my brain insists it looks like the foreground fish is wearing a party hat. #deepsea #marinelife
www.nhm.ac.uk/discover/new...
www.nhm.ac.uk/discover/new...
January 5, 2026 at 2:49 PM
The deepest confirmed fish observation occurred at ~8,300 m. I know the shape behind it is another fish’s tail, but my brain insists it looks like the foreground fish is wearing a party hat. #deepsea #marinelife
www.nhm.ac.uk/discover/new...
www.nhm.ac.uk/discover/new...
Reposted by Dr. Catherine Macdonald
New Year’s nurse shark starts the year swimming through clear blue winter water. Let’s hope 2026 brings many more clear water days in the months ahead! 💙🩺🦈💙 #nurseshark #sharksofcoralcity #shark #newyearsday #clearwater #bluewater #coral #coralcitycamera #miami #portmiami #biscaynebay #coralcity
January 2, 2026 at 5:23 PM
New Year’s nurse shark starts the year swimming through clear blue winter water. Let’s hope 2026 brings many more clear water days in the months ahead! 💙🩺🦈💙 #nurseshark #sharksofcoralcity #shark #newyearsday #clearwater #bluewater #coral #coralcitycamera #miami #portmiami #biscaynebay #coralcity
Reposted by Dr. Catherine Macdonald
Fish At Pretty Good Place In Its Life Right Now https://theonion.com/fish-at-pretty-good-place-in-its-life-right-now-1819573188/
January 2, 2026 at 4:00 PM
Fish At Pretty Good Place In Its Life Right Now https://theonion.com/fish-at-pretty-good-place-in-its-life-right-now-1819573188/
Reposted by Dr. Catherine Macdonald
ROV pilots filmed this giant phantom jelly, or Stygiomedusa gigantea, at 253 meters during an ROV descent to explore the Colorado-Rawson submarine canyon wall. #ArgentinianDeepSeeps
January 2, 2026 at 12:07 AM
ROV pilots filmed this giant phantom jelly, or Stygiomedusa gigantea, at 253 meters during an ROV descent to explore the Colorado-Rawson submarine canyon wall. #ArgentinianDeepSeeps