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Varoon Supratya @varoon-supratya.bsky.social · Jul 18

For #phycologyfriday: The unusual fishhooks of Bonnemaisonia californica
#rhodophyta #algae #seaweed #intertidal #marinelife #redalgae #marinebiology #science

A magnified view of a finely branched scarlet red seaweed. The main axes have occasional enlarged branchlets that look like swollen hooks

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Reposted by Varoon Supratya

Siobhan Schenk @siobhanschenk.bsky.social · Jul 11

Halosaccion glandiforme at Whiffin Spit. This red algae fills with water, likely to prevent desiccation.

🦑 #PhycologyFriday #Intertidal #tidepools

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Varoon Supratya @varoon-supratya.bsky.social · Jul 11

Today for #phycologyfriday: two commonly confused PNW kelps next to each other, from the same site (Whiffin Spit, BC). Left is Saccharina latissima, right Hedophyllum nigripes.
#marinelife #intertidal #pnw #biology #marinebiology #science #kelp #seaweed

Two large bladed kelps lying next to one another on an eelgrass bed. The left kelp is Saccharina latissima, with a narrower and lighter colored blade and stipe, while the right kelp is Hedophyllum nigripes, with a broad dark blade

A close up of the stipes of two large kelps. Saccharina on the top has a narrow rounded stipe, Hedophyllum nigripes on the bottom has a broad flattened stipe

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Reposted by Varoon Supratya

Siobhan Schenk @siobhanschenk.bsky.social · Jul 10

Pretty barnacles and sponges

🦑 #intertidal

A colony of pink sponges on the bottom of a rock. The top of the rock is colonized by barnacles

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Reposted by Varoon Supratya

Siobhan Schenk @siobhanschenk.bsky.social · Jun 27

For this #PhycologyFriday I'm happy to share my ✨new paper✨ about #kelp disease -> rdcu.be/ets28

Pink-spot disease occurs in kelp nurseries across North America and Europe according to our survey and we identified a bacteria (Algicola sp.) as the likely causative agent.

🦑 #aquaculture

A very extreme and unusual presentation of pink-spot disease on a kelp spool

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Varoon Supratya @varoon-supratya.bsky.social · Jun 27

Today for #phycologyfriday: Soranthera ulvoidea, a saccate brown alga that grows only on some species of red algae (in this case Odonthalia floccosa)
#marinelife #tidepools #algae #seaweed

Brown, ball shaped seaweed with wrinkled surfaces grow in a grapelike cluster on a different species of finely branched seaweed in a rocky intertidal zone

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Varoon Supratya @varoon-supratya.bsky.social · Jun 13

Lab grown stipeless bull kelp to reduce tangling in tumble culture. Removal of the stipe before the internal cavity inflates results in the cut sealing over to form a "knot" instead of the usual pneumatocyst + stipe
#phycologyfriday #kelp #marinebiology #science #algae #seaweed

Three unusual looking bull kelp that lack the usual pneumatocyst and stipe

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Varoon Supratya @varoon-supratya.bsky.social · May 30

A gumboot chiton in a medley of seaweeds #phycologyfriday #intertidal #tidepool #marinelife

A mix of predominantly brown and red algae growing off a cobble bottom, with a submerged gumboot chiton in the middle

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Reposted by Varoon Supratya

Siobhan Schenk @siobhanschenk.bsky.social · May 30

My ✨new paper✨ looking at how low salinity and high temperatures alter the bacterial community of sugar #kelp was just published!

Lab and field results agree: the overall changes are small, but core taxa decrease under abiotic stress

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

#PhycologyFriday 🦑

Part of figure 1 for the paper. There is a map of the field sites and an overview of the lab experiment. Field measurements were temperature and salinity. Lab was only salinity

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Varoon Supratya @varoon-supratya.bsky.social · May 9

Honoured to have been able to make speaker gifts for the 2025 international seaweed symposium! #phycologyfriday #iss25 #pottery #ceramics #kelp

A three tiered display of brown mugs featuring handles that look like bull kelp stipes and blades that wrap around the mug body

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Varoon Supratya @varoon-supratya.bsky.social · May 2

P1: Monthly macroalgal surveys reveal a diverse and dynamic community in an urban intertidal zone
P2: Effects of thermal stress on sorus formation in bull kelp Nereocystis luetkeana
P3: Kelps on demand: closed-system protocols for culturing large bull kelp sporophytes for research and restoration

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Varoon Supratya @varoon-supratya.bsky.social · May 2

A very unexpected find: Laminaria ephemera at Stanley Park in a seaweed diversity survey quadrat! I'll be presenting on this project (and others) at #ISS25 - see comments for details.
#phycologyfriday

Two hands holding an individual Laminaria ephemera kelp up for a photo. The kelp is small but a dark spore patch is already visible near the blade base. The holdfast is attached to a pebble which is being held. In the background, the lionsgate bridge is visible.

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Reposted by Varoon Supratya

Siobhan Schenk @siobhanschenk.bsky.social · Apr 11

Drift Lessoniopsis for #PhycologyFriday.

Lessoniopsis lives in very wave exposed areas. If you look closely at the stipes, you will find holes made by burrowing amphipods

🦑🧪🌊

Dark brown kelp with light brown stipes on sand. The stipes are short and woody

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Varoon Supratya @varoon-supratya.bsky.social · Apr 11

Blink and you miss it: the spring bloom of Laminaria ephemera, one of the shortest-lived and smallest kelps

#phycologyfriday #intertidal #marinelife #kelp #science

Narrow golden brown blades of the kelp Laminaria ephemera hang from a rock mingled with young blades of other kelp species, filmy ulvoid green algae and various red algae

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Varoon Supratya @varoon-supratya.bsky.social · Apr 4

One of the few kelp species that can spread clonally through a rhizomatous holdfast

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Varoon Supratya @varoon-supratya.bsky.social · Apr 4

A rarity in Canadian waters: Laminaria sinclairii at French Beach, BC.

#laminaria #phycologyfriday #kelp #seaweed #intertidal #marinelife #science #marinebiology #algae

A dense cluster of brown kelp hangs from a half submerged rock. Long dark stipes rise from a hidden rhizomatous holdfast and terminate in straplike, translucent blades

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Reposted by Varoon Supratya

Dr. Brooke Weigel @brookeweigel.bsky.social · Mar 28

For #PhycologyFriday, check out this gorgeous red algae (possibly Gloiocladia laciniata) that appears iridescent blue / purple underwater! Photo taken underwater ~6 m depth 🤿

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Reposted by Varoon Supratya

Adi Khen @adlysia.bsky.social · Mar 14

Closeups of historical seaweed pressings from the University Herbarium in Berkeley for #PhycologyFriday

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Varoon Supratya @varoon-supratya.bsky.social · Mar 21

Today for #phycologyfriday: a couple of tiny bull kelp sprouting from the shell of a dogwinkle

#bullkelp #nereocystis #kelp #phycology #seaweed #algae #marinelife #intertidal #marinebiology #science #tidepool

Several small bull kelp sprouting from the top of a dogwinkle (marine snail) shell

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Reposted by Varoon Supratya

jensmith11.bsky.social @jensmith11.bsky.social · Mar 8

Happy #PhycologyFriday #Seaweed #Art

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Varoon Supratya @varoon-supratya.bsky.social · Mar 14

Today for #phycologyfriday: the gorgeous Erythrophyllum delesserioides, found along exposed, wave-swept coasts of the PNW

#redalgae #erythrophyllum #phycology #marinelife #intertidal #marinebiology #seaweed #algae #science #botany

Narrow blades of seaweed moving in the current. The blades are dark blood red with striking pale veins

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Varoon Supratya @varoon-supratya.bsky.social · Mar 7

Antithamnionella spirographidis under a microscope. Collected at Stanley Park during a long term macroalgal survey by @siobhanschenk.bsky.social and I that was recently accepted as a paper cdnsciencepub.com/doi/abs/10.1...

#phycologyfriday #marinelife #intertidal #seaweed #marineecology #science

A microscopic view of a filamentous red alga called Antithamnionella spirographidis. The alga is a filament made of cylindrical cells, with a herringbone-like branching pattern and large, round and dark sporangia at the base of each branch

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Reposted by Varoon Supratya

Siobhan Schenk @siobhanschenk.bsky.social · Mar 7

Some Codium setchellii on a drift Pterygophora californica holdfast for #PhycologyFriday

Close up of the holdfast. The algae are washed up on sand.

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Reposted by Varoon Supratya

Chris Neufeld @cneufeld.bsky.social · Feb 28

From the edge of the Pacific in BC, Canada...

I offer the compact but mighty 'Sea Palm', Postelsia palmaeformis, for this #PhycologyFriday.

"I will bend but I will not break"

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Reposted by Varoon Supratya

S. W. Lawrence, MD @swlawrence.bsky.social · Mar 1

Curr. Biol. (2025) 10.1016/j.cub.2024.12.025 Kelp forests are integral + critical to aquatic ecosystems, but species such as giant kelp + bull kelp have experienced population bottlenecks in recent decades.

Giant kelp. In particular, kelp forests are declining in many parts of the northeast Pacific, practically right off my doorstep where we live close to Puget Sound [Salish Sea]. "Bemmels et al. sequenced the genomes of 429 bull kelp (Nereocystis luetkeana) and 211 giant kelp (Macrocystis sp.) from the coastlines of British Columbia and Washington." They found 'low effective population size was associated with low genetic diversity and high inbreeding coefficients (including increased selfing rates), with extreme variation in these genetic health indices among bull kelp populations but more moderate variation in giant kelp.' They found fewer deleterious variants than predicted, but suspect their loss was more likely due to genetic drift rather than purging. "The researchers predict (1) reduced within-population inbreeding depression in small populations, which may be associated with an observed shift toward increased selfing rate, and (2) hybrid vigor in crosses between small populations." These findings inform several possible strategies for optimal sourcing and crossing of populations for restoration + aquaculture. Kelp have keystone ecosystem functions, but also represent a potential source of both biofuel + agricultural amendments.

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