Fredrik Ryderheim's Avatar

Fredrik Ryderheim

@fryderheim.bsky.social

Plankton ecologist. Postdoc at the University of Copenhagen.

247 Followers  |  143 Following  |  11 Posts  |  Joined: 06.09.2023  |  2.0164

Latest posts by fryderheim.bsky.social on Bluesky

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Upptäckten: Hundratals döda fiskar i Höje å Lommabon: ”Det är tragiskt.”

www.sydsvenskan.se/lomma/hundra...

14.02.2026 12:14 — 👍 0    🔁 0    💬 0    📌 0
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First time doing field work in 8 years 😵‍💫 Local newspaper reported lots of dead fish floating around Lomma harbor. Lack of oxygen is the likely explanation, but is it the cold weather/stagnant water or perhaps something microscopic? Looking forward to analyzing samples next week in the lab.

14.02.2026 12:14 — 👍 0    🔁 0    💬 1    📌 0

Phytoplankton empiricists: anyone have a good protocol (or reference) for treating fungal contamination in stock cultures without re-isolating? 2026 continues bringing all the icks...

23.01.2026 17:56 — 👍 1    🔁 5    💬 1    📌 0

Happy to see our analysis on scaling up temperature x nutrient interactions from populations to communities published in Ecological Monographs @esajournals.bsky.social! 📈

09.12.2025 15:21 — 👍 39    🔁 14    💬 1    📌 0

Hey #microbialsky - anyone looking for a good PhD student this cycle? Ugrad from my lab is looking but no luck with the PIs she has contacted (no funding, no response). She worked in my lab for 1.5 years, now is a research tech at the FWC research institute. Excellent at the bench & super smart!

26.11.2025 01:36 — 👍 4    🔁 6    💬 2    📌 0
Journal of Plankton Research Call for Papers: Advances in Planktonic Harmful Algae Research from Marine and Freshwater Environments. Submit by 15 March 2026.

Journal of Plankton Research Call for Papers: Advances in Planktonic Harmful Algae Research from Marine and Freshwater Environments. Submit by 15 March 2026.

Has ICHA 2025 left you inspired? Journal of Plankton Research is seeking submissions for an upcoming special issue exploring harmful algae dynamics in both marine and freshwater systems.

Submit your next paper with us: oxford.ly/48FyrpP

24.10.2025 16:00 — 👍 2    🔁 3    💬 0    📌 0
Poster for 90 minute workshop on HOW TO DESIGN BETTER EXPERIMENTS, by Mridul Thomas & Ravi Ranjan. 

Details: September 23rd 16:00 CEST ; 14:00 UTC

Description: 

Experimental designs can make or break an experiment. A good experiment has a clear goal and efficiently uses experimental resources to achieve that goal. In this workshop, we will review what experiments are for, basic and advanced principles of designing experiments, and how to use simulations to evaluate designs before actually doing the
experiment. We’ll do a moderate amount of coding in R and so experience with this would be helpful but is not required. We intend to have small-group discussions to help participants develop their own experiments, and encourage participants to think of a specific question they would like to answer with an experiment.

Poster for 90 minute workshop on HOW TO DESIGN BETTER EXPERIMENTS, by Mridul Thomas & Ravi Ranjan. Details: September 23rd 16:00 CEST ; 14:00 UTC Description: Experimental designs can make or break an experiment. A good experiment has a clear goal and efficiently uses experimental resources to achieve that goal. In this workshop, we will review what experiments are for, basic and advanced principles of designing experiments, and how to use simulations to evaluate designs before actually doing the experiment. We’ll do a moderate amount of coding in R and so experience with this would be helpful but is not required. We intend to have small-group discussions to help participants develop their own experiments, and encourage participants to think of a specific question they would like to answer with an experiment.

@raviranjan.bsky.social & I are teaching a free online workshop with on experimental design for environmental scientists on the 23rd.

We'll focus on using simulations to evaluate how well different experimental designs help achieve your goals.

Please sign up & share! forms.gle/MZTxeQs4UpMr...

15.09.2025 11:20 — 👍 27    🔁 21    💬 2    📌 2
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Mapping the transcriptional landscape of algal resistance to viral infection reveals a core expression program Algal blooms and their demise by viruses drive global-scale ecological processes in the ocean. These blooms form the foundation of marine food webs, regulate microbial communities, and shape biogeoc...

📣 We are excited to share our latest paper, led by @taliashaler.bsky.social! We explore the transcriptional basis of #microalgae resistance to #viral_infection and identified a core group of resistance-related genes. >>
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#New_Phytologist #Marine_Biology #Viruses

04.09.2025 11:03 — 👍 22    🔁 12    💬 2    📌 0
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What could be more exciting than watching Euplotes scurry around under the microscope? How about adding some raptorial predation by supergiant cannibal cells?

www.biorxiv.org/content/10.1...

Video by Vittorio Boscaro.

1/n

26.08.2025 20:56 — 👍 113    🔁 37    💬 3    📌 11
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PhD Scholarship in marine fish habitats in Denmark - DTU Aqua We are looking for a motivated PhD candidate to explore how fish distribution and habitats are linked across coastal and offshore waters in Denmark. The project focuses on improving our understanding ...

#PhD Scholarship in #marine #fish habitats in Denmark

...at DTU Aqua with a very good colleague of mine.
#jobalert

efzu.fa.em2.oraclecloud.com/hcmUI/Candid...

13.08.2025 14:18 — 👍 0    🔁 1    💬 0    📌 0

Sequestration by the biological carbon pump: Do we really know what we are talking about? aslopubs.onlinelibrary.wiley.com/doi/10.1002/... #jcampubs 🌊

12.08.2025 13:09 — 👍 6    🔁 2    💬 0    📌 1
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We have a postdoc opening for a protistologist with biophysics inclinations to join our @hfspo.bsky.social project! (focus will be on characterising the morphology, ultrastructure and behaviour of excavates) #protistsonsky

Apply by Sept 17th (RTs appreciated!)
jobs.exeter.ac.uk/hrpr_webrecr...

06.08.2025 19:19 — 👍 47    🔁 49    💬 1    📌 0
Nutrient Co-limitation of Marine Microbes: Exploring Cellular to Ecosystem-Level Effects Nutrient availability limits microbial growth in marine ecosystems globally. Accumulating evidence has highlighted the prevalence of nutrient co-limitation, whereby two or more nutrients restrict mari...

🌊Curious how multi-nutrient scarcity impacts marine microbes🦠? Excited to announce our #OSM26 session, Glasgow Feb 22-27! Join us in bridging cell biology, modelling & oceanography! tinyurl.com/zzt5s9su @exetermarine.bsky.social @thembauk.bsky.social @proteocean.bsky.social @cmarkmoore.bsky.social

31.07.2025 08:34 — 👍 9    🔁 6    💬 0    📌 0

Still debating attendance? Check out the amazing souvenir mugs that our lab technician, Julian Jacobs, has made for the occasion! #TraitBasedApproaches #Traits2025

28.07.2025 15:31 — 👍 10    🔁 2    💬 1    📌 1
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Seventh Workshop on Trait-based Approaches to Ocean Life The 7th Workshop on Trait-based Approaches to Ocean Life will bring together scientists to discuss how functional traits shape marine ecosystems, using experimental, statistical, and modeling approach...

Trying to develop predictive theory for how biology works in the ocean? Interested in unifying traits? Keen to hang out in a beautiful place with amazing people? Consider joining us in a couple of weeks at the 7th #TraitBasedApproaches workshop in Asilomar! carnegiescience.edu/seventh-trai...

19.07.2025 23:15 — 👍 23    🔁 12    💬 1    📌 1
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Intraspecific differences in the effects of salinity and light on growth and prymnesin cell quota in Prymnesium parvum The haptophyte Prymnesium parvum produces large polyether compounds (prymnesins) with lytic properties that accumulate in the cell or may be released …

In our study on Prymnesium parvum, we found that low salinity inhibits prymnesin production, while slower growth leads to higher cellular toxin quotas. Intraspecific differences may help explain bloom success across environments.

#openaccess in Harmful Algae

www.sciencedirect.com/science/arti...

16.07.2025 11:56 — 👍 3    🔁 0    💬 0    📌 0
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Predator-induced defense reduces growth rate and carrying capacity in a toxic diatom, Pseudo-nitzschia seriata Phytoplankton employ a wide variety of defenses to reduce mortality from zooplankton grazing. Many such defenses are inducible, that is, they are upre…

Our latest paper on predator-induced defense is now out in Harmful Algae. We show that Pseudo-nitzschia seriata induced to produce more domoic acid grow slower and, because of increased cellular N, produce less cells as nutrients become depleted.

www.sciencedirect.com/science/arti...

09.07.2025 17:45 — 👍 0    🔁 0    💬 0    📌 0
A blue poster describing opportunities to join the Bernhardt Lab -- for more information please see https://www.bernhardtlab.org/join-us

A blue poster describing opportunities to join the Bernhardt Lab -- for more information please see https://www.bernhardtlab.org/join-us

✨ The Bernhardt Lab at the University of Guelph is recruiting graduate students for 2026! Join us! We have several fully funded grad positions available ✨

Please spread the word!

www.bernhardtlab.org/join-us

#CSEE2025

07.07.2025 23:21 — 👍 106    🔁 101    💬 1    📌 2
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Are you interested in how diatoms communicate with each other? Exciting post-doc position available in my lab to study the signalling mechanisms of cell-cell communication in diatoms. Deadline 14th July. @kehelliwell.bsky.social @thembauk.bsky.social www.jobs.ac.uk/job/DNO210/p...

04.07.2025 07:18 — 👍 42    🔁 24    💬 1    📌 3
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Excited to share the lab's 1rst preprint! Rapid high-res immunofluorescence is now possible in cultured & environmental diatoms thanks to 4-fold expansion microscopy. A step-change for comparative cell biology in one of the most important phytoplankton groups on the planet 🥳
tinyurl.com/m9s5su7s 1/2

17.06.2025 07:33 — 👍 322    🔁 89    💬 8    📌 19

A modular, open source Scanning Particle Image Velocimetry system for spatial mapping of flow, oxygen concentration and boundary layers around aquatic organisms/samples.
Great collaborative work headed by @pacherres-co.bsky.social

@moorefound.bsky.social @villumscience.bsky.social @MSCActions

13.06.2025 11:02 — 👍 5    🔁 2    💬 0    📌 0
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Take a look at our new article where we present a system to spatially map oxygen and flow fields around corals and algae 🪸

besjournals.onlinelibrary.wiley.com/doi/10.1111/...

Thanks to @microsensing.bsky.social @MSCActions @villumscience.bsky.social

12.06.2025 14:37 — 👍 7    🔁 2    💬 0    📌 1
The sandeel's sense of sand The sandeel plays an important role in the marine ecosystem as a key species in the food chain. Now research shows that sandeels are picky about the sandy bottom where they burrow – and this makes them vulnerable to potential changes to their habitats, which are sand and gravel banks.

Sand is not just sand when you are a #sandeel.
Read about one of our studies that came out last year in JEMBE.
#fish #teamfish
@elsevierconnect.bsky.social

www.aqua.dtu.dk/english/news...

16.05.2025 10:33 — 👍 2    🔁 1    💬 1    📌 1
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David Attenborough’s Ocean reveals how bottom trawling is hurting sealife in horrifying detail Industrial fishing has caused immense damage to ocean life, but given the right protection, the sea has miraculous powers of recovery.

The footage of bottom trawling alone makes the film worth watching. Let’s hope this destructive method of killing ocean creatures is outlawed soon.

08.05.2025 21:02 — 👍 203    🔁 73    💬 4    📌 1
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NIOZ - Postdoc position (45 months):“Marine phytoplankton – virus interactions and loss rates from small to ocean scale” The Department of Marine Microbiology and Biogeochemistry (MMB; principal investigator and PHYVIR project coordinator Prof. Dr. Corina Brussaard) of NIOZ is looking for a talented and dedicated Postdo

Another position within the PHYVIR project 😁.
Are you looking for an interesting Postdoc (45 month!) on marine viral ecology? Check out the ad below.
workingat.nioz.nl/o/postdoc-po...

03.05.2025 06:40 — 👍 6    🔁 9    💬 0    📌 0
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The diatom–copepod arms race Kiørboe and Ryderheim introduce the competitive arms race between copepods and their diatom prey.

We wrote a 'quick guide' on the diatom–copepod arms race. Published today in @currentbiology.bsky.social

www.cell.com/current-biol...

21.04.2025 17:20 — 👍 6    🔁 1    💬 0    📌 0
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🚨 3-year Postdoc Opportunity! Join me and the Aquatic Ecosystem Analysis group @UniKoblenz. 🔬 Microbial #ecology, #protist predation, #algae #plankton & flexibility | 💻 Environmental -omics | 🌊 Rivers 📅 Apply by May 15 | 🔗 kennethdumack.de | tinyurl.com/dumack
Please share! #MicroSky #ProtistsOnSky

16.04.2025 07:46 — 👍 15    🔁 21    💬 2    📌 1
Postdoctoral researcher in Plankton Ecology // University of Oldenburg

We offer a 5-year research position in the #PlanktonEcology lab in Wilhelmshaven. Are you interested in empirically testing ecological concepts? We offer a stimulating scientific environment, experimental facilities & support to establish an independent research profile
uol.de/en/job/postd...

15.04.2025 17:59 — 👍 60    🔁 76    💬 0    📌 2
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BSNCN

Come and talk Baltic Sea nitrogen with us in Uppsala May 13-15, a workshop hosted by the Baltic Sea Nitrogen Cycling Network balticnitrogen.com for registration please visit: www.slu.se/en/ew-calend... listen to talks and mingle around posters, and exchange ideas on what’s needed in the future.

03.04.2025 16:34 — 👍 6    🔁 5    💬 1    📌 1
Professorship in Theoretical Physical Oceanography // University of Oldenburg

@icbm-uol.bsky.social offers a fully funded professorship in theoretical oceanography. Join a great team of physicists, chemists, and biologists working on the marine environment. Oldenburg is a truly livable city and connected to a range of marine institutes in NW Germany

uol.de/en/job/w2-pr...

03.04.2025 17:47 — 👍 41    🔁 38    💬 1    📌 0

@fryderheim is following 20 prominent accounts