Join me in the cold, dark, life-sustaining NE Pacific Ocean to discover the great beauty, mystery and fragility hidden there.

Posts by The Marine Detective

Found! Cryptic Nudibranch

I finally observed some of the most cryptic nudibranchs on our coast! 💙

The Cryptic Nudibranchs you see here are only about 1 cm long and look at how astoundingly evolved they are! They are virtually invisible on the Kelp-encrusting Bryozoan which is growing on Bull Kelp at this time of year. This species of nudibranch is also known as Steinberg’s corambe (Corambe stinbergae to 1.7 cm).

You can see in the photos here that we found some of the nudibranchs mating and there were many of their egg ribbons (each of those coils has a lot of eggs that result from both parents becoming inseminated and laying eggs).

You can also see where they have been feeding on the bryozoans (colonies of animals).

I have looked for them for years knowing their range is from Alaska to Baja California, Mexico.

Mating: Right-side-to-right-side attached via the gonophores. Both hermaphrodite parents lay eggs.

What made the difference in now being able to find them:

(1) Getting the clue from Robin Agarwal to look at the kelp fronds that were REALLY tattered with the Kelp-encrusting Bryozoan colonies .

(2) Having a skilled dive buddy willing to join me in burying our heads in old, tattered kelp in the surge for 30 minutes instead of looking at all the big, colourful life at this dive site. Thank you Janice Crook!

(3) Once we knew what the egg ribbons looked like (those s-shaped little masses), we had a really good clue and knew better where to look even more closely for the nudibranchs.

Now on to finding the SECOND really cryptic nudibranch species that feeds on Kelp Encrusting Bryozoans – Corambe pacifica to 1.5 cm long and whose egg masses are tiny, flat coils.

For more photos and my previous blog on what Kelp-encrusting Bryozoans look like, please see my other blog “Kelp Lace? Bryozoans”.


Photos: September 19, 2022, Browning Pass ©Jackie Hildering, The Marine Detective.

Happy dive buddies
– Janice Crook and yours truly.

What on earth . . . and its tail is a snorkel!

Here’s one of the best mysteries I’ve been gifted recently.

It started with videos sent to me from Leesa Flynn that she had taken at Cordova Bay, southern Vancouver Island, British Columbia. Just look! What powers of observation Leesa has. This animal is less than 6 cm long and what’s with that tail?!

I did NOT know what this animal was and how my interest was piqued. I did suspect it might be an organism found in non-marine environments since it was so high up in the intertidal zone. Likely the water was not very salty where it was found.

The mystery had to be solved
I am very fortunate to have quick access to expertise far greater than my own. Those I reached out to included Rick Harbo, author of many ID guides for marine life of the Pacific Northwest. Rick did not recognize this animal, so off the videos went further into the web of expertise, intriguing many biology experts along the way.

To the relief of all, the identification came back through Hugh MacIntosh of the Royal BC Museum and Kevin Kocot of the University of Alabama. They recognized that this was a larval stage of a species of Hover Fly. The larvae are not known to be in marine environments so the water near this organism must have been from a creek flowing on the beach or highly diluted by rain.

One of the many species of Hover Fly – an Orange-spotted Drone Fly, Eristalis anthophorina.
Photo by Jimmy Dee via Wikimedia

Larva of a bee-like insect
The long tail of these larvae functions like a snorkel. It’s a breathing tube whereby larvae of Hover Flies can be underwater feeding while breathing from the surface. What a remarkable adaptation!

There are MANY species of Hover Fly and they are really important to the environment. The adults are important pollinators and the larvae recycle nutrients and some feast on pests like aphids (which parasitize on plants / crops).


But what species of Hover Fly specifically was the larva that Leesa observed? I think this mystery organism is a species of Drone Fly of genus Eristalis. I provide detail about that at the end of this blog. First let me address . . . Rat-tailed Maggots.

Rat-tailed Maggots and Bum Breathers?
I learned that the broad grouping of larvae in the family of Hover Flies appears to be referenced as “Rat-tailed Maggots”.

There’s an increased chance that you’re cringing now – right? Many of us have negative associations with the words “maggot” and “rat”.

That wonderful adaptation of the long breathing tube allows these larvae to live and feed in environments that may poor water quality e.g. sewage. As described by Real Monstrosities: “Since Rat-tailed Maggots breathe air, they have no use for gills, which in turn means they’re not particularly reliant on water quality. Thus, there’s many a Rat-tailed Maggot that lives in the squalor of cesspits, pools of sewage, watery manure or carcasses.

The one featured in this mystery is not likely to have been in water of poor water quality. It’s just that they could live and feed in those environments. They can also be terrestrial. They do tend to lay eggs in nutrient rich environments.


Here you have colourful text from IFLScience about this broad group of larvae to accompany the video above of a different species of Hover Fly larvae (not the species in this mystery).

“Rat tailed maggots are the larval form of some species of hoverfly, which can be terrestrial or aquatic. They start out life as a blob with a breathing tube, later dragging themselves onto land to pupate and turn into certain flies. Rat tailed maggots enjoy feeding on decaying organic matter which is why you’ll often find them in dank ponds and rotting trees, as well as anywhere there’s an open source of feces (including, one time, Glastonbury Festival).

They have a long breathing tube called a siphon attached to their rear end which is why some entomologists affectionately refer to them as “bum breathers”. They bulk up in their larval, rat tailed maggot form before pupating in soil or other dry material and emerging as several species of hoverfly.

You might think the rat tailed maggot is a little ugly, but they are champions for the environment both in their larval and adult forms. As rat tailed maggots, they encourage the turnover of nutrients by eating decaying matter and pooping it out again. They also predate on common plant pests such as aphids.

As adults, they’re hugely important pollinators which facilitate gene flow across isolate plant populations as they are big travelers. So, if you see a rat tailed maggot, do your bit by simply letting it do its thing.”

Screen grab from Leesa’s video.

But which larvae is this specifically?
I think that the larva in this mystery is a species in a subgrouping of Hover Flies (family Syrphidae), known as Drone Flies (genus Eristalis).

In what I was able to learn from the contributions to iNaturalist.ca, it appears there are 6 species of Drone Fly that have been found on Vancouver Island. I am hopeful that an etymologist reading this blog will be able to narrow down which one this larvae is.

The six are:
Common Drone Fly Eristalis tenax
Dusky Drone Fly Eristalis obscura
Orange-legged Drone Fly Eristalis flavipes
Orange-spotted Drone Fly – Eristalis anthophorina
Orange-spined Drone Fly 
Eristalis nemorum


Thank you so much for your interest in all creatures great and small, furred and maybe what some human brains interpret as a little freaky. These species are perfection with adaptations that ensure success in the web of life. A web to which we, of course, belong. 💙


Sources:

Screen grab of larvae from Eristalis genus from this source.

Above: Comic by UnderdoneComics.com which included the text: “Ever spend time outside and notice an insect that looks like a bee but has wings like a fly hovering near you? Well sir, that’s a hoverfly. And my favorite kind is the drone fly—because, as you can see from the comic—it has an amazing lifecycle.

Before they become bee-lookalikes, their larval stage resembles a deep sea diver. They breathe through a tube that comes out of their butt and they laze around eating plant particles. How crazy is that?”

Kelp Lace? Bryozoans.

And so it begins.
It’s the time of year when the annual kelps like Bull Kelp begin to break down. It’s then that Kelp-encrusting Bryozoans really get a chance to colonize the kelp as you see in these photos.

Every little box is an individual animal. It’s a “zooid”. The oldest member is in the middle and the others all originated from that one by asexual reproduction.

The zooids filter feed on plankton with the tentacles you see in this wonderful video by friend Karen Johnson. These crowns of tentacles are known as lophophores.


“Kelp-encrusting Bryozoan” (Membranipora membranacea) is also known as “Kelp Lace Bryozoan”. It’s no mystery how either common name was inspired. Each circular colony is approximately 20 cm wide.

If you are lucky enough to live near the Ocean, look at the kelp that washes ashore for these colonies. The colonies in these photographs where on Split Kelp (Laminaria setchellii) and Bull Kelp (Nerocystis luetkeana).

What on earth is a “bryozoan”?

From Beachkeepers: “Bryozoans are colonial animals that arrange themselves in circular (radial) fashion, often with the oldest (and first to settle) individual in the middle. . . . The ‘box’ of the zooid is made of either a tough protein (like what you would find in crab shells) called chitin, or what you would find in coral reefs, calcium carbonate. This body box has an opening where the bryozoans extend their feeding apparatus (that looks a lot like a sea anemone) called a lophophore. Yes, they have predators! [Some species of] nudibranch will eat them, though they can reproduce asexually to form the colony back to size after a nudibranch has been grazing on them. Sometimes, when they grow back, they’ll even grow chitonous spines on their body walls to discourage the nudibranchs from coming back. These spines usually form on the individuals on the outside edge of the colony.”

Adalaria nudibranchs feeding on the bryozoan.
Blue Turban snail feeding on Kelp-encrusting bryozoan.
Opalescent Nudibranch near a colony of Kelp-encrusting Bryozoan.

Detail about this bryozoan species – Kelp-encrusting Bryozoan.
From Invertebrates of the Salish Sea: “Bryozoans start from a single individual zooid (an ancestrula) which repeatedly reproduces asexually to form a colony. In this species, the oldest individual is in the middle. Colonies of this species usually begin to be noticeable in late spring and grow through summer into fall. By fall they may form extensive crusts on the kelp and many colonies have merged with one another. In many bryozoans there are various types of zooids but in this species there is only one type of zooid which serves for feeding, for reproduction, and for defense. The colony appears to be a simultaneous hermaphrodite, or male zooids may develop first. They do not brood their young. Eggs are fertilized then released, and quickly develop into cyphonautes larvae which may feed and develop as plankton for several months. The larvae settle when they encounter kelp such as Laminaria or water with an excess of potassium ions. The small white nudibranch Doridella steinbergae [reclassified to Corambe steinbergae] may be found living and feeding on these colonies but it blends in so well it is difficult to see . . .”
Note there is a second similar looking cryptic nudibranch that can found on these bryozoans and that is Corambe pacifica. Corambe pacifica has a notch at the back. Corambe steinbergae does not.
I have never managed to find these cryptic nudibranchs. Grateful to Karolle Wall and Robin Agarwal for their photos below.

What happens to the kelp?

It is the natural cycle of kelp species like Bull Kelp, that at this time of the year, the large version (the sporophyte) begins to break down. Spore packets drop to the bottom of the Ocean which create a different version of the kelp. It’s Alternation of Generations and here is my blog about that wonder. Other kelp species like Giant Kelp are not annuals. They remain year round.

Spore packets (in the centre of the kelp fronds).

All photos (other than those by Karolle Wall and Robin Agarwal) were taken in early August near northeast Vancouver Island in Kwakwaka’wakw Territory ©Jackie Hildering.

Additional information:

Hageman, Steven J., et al. “Bryozoan Growth Habits: Classification and Analysis.” Journal of Paleontology, vol. 72, no. 3, 1998, pp. 418–36. JSTOR

Note: Some report that this species of bryozoan is an invasive in the Atlantic. However, “recent genetic studies indicate that this species is a complex of a number of long-separated clades. The only verified invasion is its introduction from the Northeast Atlantic to the Northwest Atlantic” (Source: Nemesis).

Whorling Wizardry

Here’s a big dose of wonder for you.

It’s the time of year when female Oregon Tritons are laying their eggs. These are BIG, predatory marine snails at up to 15 cm long.

Look at how many fertilized eggs are in each “capsule” and marvel at the shape of the egg mass. These capsules are referenced as “sea corn” for this species. It takes each female about 2 weeks to lay her eggs in this wondrously shaped clutch. A friend referenced the shape of the egg mass as being reminiscent of Van Gogh’s “Starry Night”. Agreed!

See the “blank” egg capsules? They have likely been preyed upon e.g. by shrimp, hermit crabs or other snail species. You can even see hermit crabs and snails in these images feeding on the eggs. Some hermit crabs are even sitting on females as they lay eggs. Oh the cheek!

See the hermit crabs and “blank” egg capsules?
I could not resist providing a closeup on this Whiteeknee Hermit from the previous photo.
Look at those eyes!
Closeup on a Blue Turban snail snacking on eggs (from previous photo).

Almost every time I see Oregon Tritons lay eggs, they are doing so as a group. Reportedly, up to 30 individuals have been found laying eggs together.

Why are there so many eggs? Because chances of survival are so low when there is no parental care (other than the architectural marvel of the egg case) and the young hatch into the soup of the Ocean. Planktonic larvae hatch out of the eggs at about 2 weeks of age.

With it taking 2 weeks for the young to hatch, and 2 weeks for Mom to lay the whole mass, the first capsules could be hatching by the time she is finishing her work. I learned from aquarist Casey Cook from her microscopic observations at the Aquarium of the Pacific that, “By hatch time there are significantly less in the egg [capsules] than at the beginning of the lay. We presume the babies eat each other to gain nutrients for creating their first shell layers.”



One study found that, in an aquarium, the larval stage for this species was up to 4.6 years and they only began metamorphosis into their adult form when something was available for them to settle on e.g. rocks (Strathmann and Strathmann, 2007). Further “time from metamorphosis to first reproduction was 3.3 years” (in these conditions in the aquarium).

The scientific name for Oregon Tritons is Fusitriton oregonensis. That’s a whole lot of Oregon in their name and the species is the official seashell of Oregon state (there’s trivia for you). However the range for this species is well beyond Oregon. They are found from northern Alaska to northern Mexico, and Japan. They are common around northeast Vancouver Island. Depth range is reported to be from the intertidal to 180 m. In my experience they are rarely in the intertidal however.

They are also known as the Hairy Triton. “Hairy” for the bristly “periostracum” you see atop the shells which appears to stop attachment of marine organisms. Some loose this bristly covering and, resultantly, can have a lot of settlement and growth on their shells.

The brown structure you see at the opening of the shell is the operculum. This is hard and made of keratin and serves as the door to close the shell. More about that in my “Shut the Door!” blog at this link.

Predatory? Yes! They are among the marine snail species that drill holes into prey, sedate, and slurp. From Invertebrates of the Salish Sea: “Feeds on ascidians, urchins, bivalves, sea stars, brittle stars, chitons, abalones, and polychaetes [worm species] . . . It produces sulfuric acid in its salivary glands, which may help in boring through shells. A gland in the proboscis secretes an anaesthetic used for subduing prey. It feeds with biting jaws as well as a radula . . . Humans should not eat this snail because it carries a pathogen in its salivary glands which can be fatal to humans.”

I have also seen this species scavenge on dead crabs, anemones and fish and eat Lingcod eggs.

Oregon Tritons scavenging on the head of a Lingcod.
Oregon Tritons mating. I hope you appreciate the mood lighting.

All photos: ©Jackie Hildering, northeast Vancouver Island in unceded Kwakwak’wakw Territory.

Oh look! It’s a Scalyhead Sculpin (indicated with arrow).

Octopuses Have Arms

Big questions often come from little people and there are so many times that I have been asked by children why I reference the limbs of an octopus as “arms” and not “tentacles”.

Here’s why:
Arms have suckers down the full length of the appendage. Tentacles only have suckers near the tip. Thereby, all eight octopus appendages are arms while squid have two tentacles and eight arms. Further, the purpose of tentacles is generally limited to feeding where arms have more functions. Octopuses use their limbs for feeding, locomotion, reproduction (if male*), defence, etc!

Oh and why are they called “arms” vs. “legs”? Because octopuses’ appendages have more purposes than just locomotion.

Octopus walking on her arms (and you thought YOU were special 😁). How to know this is a female octopus? See below for the link to my blog* on octopus sex.

There are scientists who have put forward that some octopus species use two of the limbs mostly for locomotion whereby they would have two “legs” and six “arms” but let’s avoid that debate!

While we are on the topic of semantics and cephalopods, and anticipating that there will be those who question my use of the plural form of “octopus”, please note the origin of the word octopus is Greek, not Latin. Thereby “octopuses” or “octopods” is truly more correct than “octopi”. 😉 From a strict linguistic perspective, the most correct is “octopods” but I choose not to use that. I think if I were to say “octopods” it would distract what I am trying to communicate that is more important that grammar. I might also come across as pretentious and have fewer human friends 🐙.

There, don’t you feel much better armed to speak for our awe-inspiring eight-legged neighbours? Or, are you up in arms?


*Related blog: Giant Pacific Octopuses – How Do They Mate?

Scuba Sisters

Here’s to the salty sisterhood of cold-water divers (and the men with whom we submerge). I am a week late with posting this for “Women’s Dive Day”. Yes, it’s been busy.

But, it’s still really important to me to put these photos into the world and reflect on how much this sisterhood means to me, and why. I have tears in my eyes as I type this, so apparently, the feelings run deep.

Scuba sister Jacqui Engel with Egg Yolk Jelly.

Why? Because you may have noticed that, by some, there is an increasing downward pressure on womxn in an attempt to limit the spaces in which we expand and the choices we WILL make. Because some want to hold on to the assumption of inherent privilege based on the absurd “criteria” of skin pigmentation; whether one’s chromosomes have one X or two; or gender identification. Because some fight equality to claim superiority.

I now have some pretty good expletives in my head which I will not type here.

Scuba sister Natasha Dickinson and Sunflower Star. We documented the same one over a span of 71 days. It’s the sea star species that was / is impacted the most by Sea Star Wasting. This individual is on an anchor block covered with encrusting coralline algae.

Of many examples of times it has become very clear to me that being a womxn* in science and scuba is important, let me share the following:

On a really hot day, I was “show and tell” for two children in our community. I dressed up in all my dive gear (the full weight and heat of it) and walked down the hallway and into the classroom with Cayden’s little hand in mine on one side, and Sophia’s little hand in mine on the other.

I walked in as a surprise to the other students. I then was gifted the time to talk about the science of the dive gear and the life that lived in the cold Ocean; our neighbours who were just below the surface of where we lived.

I took the equipment off piece by piece after explaining what it did. The children chose to try to lift the weights and cylinder and we discussed pressure and buoyancy (always good metaphors 🙂 ).

In the course of this, among so many moments the filled my heart, a little boy looked up at me. He had such an open expression on his face and he said . . . “You’re my first scuba diver”.

I was his first scuba diver – me an older woman, speaking for science and the sea, engaging not in an elevated way but in a way that invited them all to follow where their loves took them, and yes, I was wearing a bright green tutu.

Scuba sister Janice Crook.

How does this help shape the future? We will never know will we? We are all projecting our energies and images into places where we might increase what is good in the world, or suppress it.

From the depths, love to you my scuba sisters, and to the men we swim beside. Respect and gratitude to all who shine their light so that others may follow; who do NOT push others down in an attempt to feel elevated. That’s such a tragic and transparent indicator of being a hollow human.


Below: A slideshow to honour some scuba sisters.

For those that may not have seen the use of “womxn” before. The spelling of womxn is a feminist choice in two ways. It removes the “m-a-n” from “woman” and “m-e-n” from “women”. It’s also an acknowledgement that I am including trans and non-binary humans when I use the word.

I Want for Rights . . .

The is not a scientific post. It is an #OceanVoice post = my thoughts about hope, connection, equality and positive action for future generations.

Scenery The Marine Detective
Mother Ocean. NE Vancouver Island, Kwakwak’wakw Territory ©Jackie Hildering

I posted the following on social media last night with the text:
“I needed to write this for myself.
May it land with those who need it too.”

The reaction to the poem suggests it may be of value to readers here too. Here goes.

I want to hide
Below the waves
Where man
Does not decree

I want escape
From values vile
That choke
Humanity

I want to be
Where those with eyes
Use them
To truly see

I want for light
To shine in dark
This way
To equality

I want for rights
So those who wrong
Shrink in . . .
Their toxicity

Bull Kelp The Marine Detective
Grow towards the light. Summer Solstice 2022.
Bull Kelp just below the surface near NE Vancouver Island, Kwakwak’wakw Territory. ©Jackie Hildering.

For more #OceanVoice, please see click here. 

Silver strands of salmon

Salmon – shiny, silvery threads of life.
Take a few minutes to marvel at the role of wild salmon in holding together the fabric of life on our coast?

June 1st is #BCWildSalmonDay.

See the salmon in Surf’s mouth?
Surf is A66, a mature male Orca belonging to the inshore fish-eating (clearly) population of threatened Northern Residents. He was born to Sonora (A42) in 1996. While “Resident” populations of Orca also eat other fish species, their well-being is correlated to availability of salmon (especially Chinook Salmon).

Whales do not randomly blunder about looking for food. Nor are salmon flailing about arbitrarily. The fabric is so much finer than that.

For thousands of years, generation-upon-generation, families of Orca have depended on the same lineages of salmon. In these dark waters, the fish-eating Orca can literally sound out location, size and species of their prey with biosonar / echolocation. Females almost always share the catch with their family (Wright et al).

Salmon fight to return to the exact rivers of their birth by some pull we human have yet to fully understand. This flow is predictable and essential. This predictability provides ease of hunting for the many who depend on the silver flow – from fish-feasting Orca to human fisherfolk. Less energy is needed because the prey SHOULD be easy to find.

The salmon are guided to spawn so that, in death, they deliver nutrients from the Ocean back to the freshwater where they were born, even hundreds of kilometres inland. That is, if transit is not impeded by drought, siltation and slides, parasites and/or disease, or by lack of cold refuges.

The rich bodies of salmon will nourish the ecosystem so that enough of their young may survive to hold the fabric together. Their bodies feed trees, bears, eagles, song birds, insects, deer, wolves, and so much more.

By spawning and dying, the salmon also ensure their diseases and parasites die with them. Nutrients remain.

This web is made of a fabric of exquisite beauty and perfection, shaped by vast expanses of time. Weathered, refined, and adapted by slow change.

But, now, change comes far too fast through the actions, and insufficient reactions, of those who do blunder and act arbitrarily. We, the humans without sufficient understanding of the intricacy of it all, nor how we are attached to the threads.

Know that what helps salmon, herring, whales – is the fabric that holds we clumsy bipeds together too.

Not disparate problems.
But the same life-enhancing solutions.

Care more. Consume less.

Photo: ©Jackie Hildering taken in 2014 in Kwakwak’wakw Territory, northeast Vancouver Island.


Related blog but with me applying Seussian style: A World Without Salmon

Life Begins Anew

Dear readers, look! Just look!

These photos are from today. The baby Bull Kelp is growing toward the sun. With these images, I have tried to capture the aching beauty of the light “dancing” over the flowing fronds, creating rippling spectrums.

I cannot express in the way I want how watching this interplay filled me with a sense of comfort, continuance, exaltation and even relief.

While humans collide, love and lose, and may not even know what winning is, this continues despite it all (at least for now).

Life begins anew . . . the marvel of another spring . Phenology.

“Our” part of the planet is now tilted closer to the sun. Tomorrow, March 20th, coincidentally is spring equinox when the sun’s rays directly grace the equator in the earth’s journey around the sun. As we spin, the northern regions of the earth will progressively get more sun. It’s the first day of spring for we in the northern half of the planet.

There is more light to fuel the kelp’s growth and leads to food, oxygen, refuge, reduced carbon dioxide and whatever this heady, healing, emotional cocktail is that I am feeling right now. 💙

I hope some of that transmits to you, through the photos and my effusiveness. ☺️


All photos here: March 19, 2022 northeast Vancouver Island in Kwakwaka’wakw Territory ©Jackie Hildering with dive buddy Natasha Dickinson.


More about this version of Bull Kelp and it’s growth rate:

Kelp species and seaweeds are not plants. They are algae.

What you see in these photos is the “sporophyte” stage of Bull Kelp (Nereocystis luetkeana). It results from the reproduction of a completely different looking version of the same species, the “gametophye”. Yes, it’s alternation of generations and I have a blog about it here.

The stipe (stem-like structure) of Bull Kelp can grow to be up to 36 m long. The stipe would have to grow an average of 17 cm a day to reach this length in the 210-day growing period (source: Druel). It has to grow so quickly to reach the sun and be able to photosynthesize and help support life on earth.

If you include both the rate of growth of the stipe and the fronds (leaf-like structures), Bull Kelp can grow 25 cm per day on average to reach the surface (source: Duncan).  


My additional posts about Bull Kelp include:


Sources:

Worms That Bite Anemones?!

Okay, this is a true mystery.

I have relayed my observations to marine worm researchers but want to share with you too. It’s just too fascinating not to do so. These finds emphasize yet again how little we know even about marine species that are just below the surface. I also hope that by sharing my observations here, it may lead to other divers being on the lookout for these interactions and potentially adding to the knowledge about interactions between necklace-worms and anemones.

Necklace-worm species #1 and Proliferating Anemone – January 1st, 2008.
Necklace-worm species #2 and Short Plumose Anemones – March 6, 2022.

My observations involve what I believe are two species of necklace-worm. Each is interacting with a different species of anemone. In both cases, the species of necklace-worm is unconfirmed. The polychaete* researchers I have been in contact with have asked for samples of the worms to allow for microscopic examination and potential DNA analysis.

*Polychaetes are the “many-bristled” worms. They are worms that have a pair of paddle-like appendages / bristles on each segment. Most species of worm in this class are found in the ocean or in brackish water and there are about 15,000 known species globally. Polychaetes “are ubiquitous in the ocean, burrowing and hunting in the sand, crawling on algal covered rocks, living in self-made tubes, or swimming in the water” (Encyclopedia of Biodiversity, 2013).

Note that observations and photos here are from the Pearse Islands and Plumper Islands on northeast Vancouver Island in the territory of the Kwakwaka’wakw in depths less than 17 metres / 50 feet.


Necklace-Worm Species #1 and Proliferating Anemones:
I have written about this previously but include the observations here again so that the information about these necklace-worm / anemone interactions is bundled in one place. It involves a species of necklace worm appearing to bite into Proliferating Anemones (Epiactis prolifera to 8 cm wide).

My first observation of this interaction goes back all the way to 2008 when I documented the following thanks to the keen eye of my dive buddy Natasha Dickinson.

Both photos: Necklace-worm species #1 appears to be biting into a Proliferating Anemone – January 1st, 2008.

I do not know if the necklace-worm dislodged the anemone of if the anemone let go in an attempt to get away. We came upon this scene when the anemone was already upside down.

I have only noted this interaction twice since then. See photos below.

Necklace-worm species #1 and Proliferating Anemone – February 15, 2015. Note the “casings” the worms are in on the left.
Necklace-worm species #1 on the right and Proliferating Anemones – February 22, 2020. [Yes, on the left, those are babies of multiple ages hanging onto their mother. More about that at this link.]

For those who have Lamb and Hanby’s Marine Life of the Pacific Northwest, you may note that this species of necklace-worm looks like AN22 which is referenced as a “mystery necklace-worm”. But again, collection of a sample would be needed to confirm species ID.


Necklace-Worm Species #2 and Short Plumose Anemones:

On February 12, 2022 I saw THIS.

Necklace-worm species #2, Short Plumose Anemones AND the spaces where these anemones used to be. Many of these anemones are retracted. Photo February 12, 2022.

There are necklace-worms in those slime tubes! Where you see the circles is where other Short Plumose Anemones once were (Metridium senile to 10 cm tall and 4 cm across).

Close-up showing the necklace-worms. Photo February 12, 2022.

Were they always at this site? I have done a quick review of past photos and see a few of them in photos back to 2013. Variables in why I may not have noticed them before are that: (1) they were much more apparent as a result of the dislodged anemones; (2) there may be more of them now; and (3) we usually don’t focus on the spot where the concentration of these worms were (we usually dive deeper).

Here’s another photo from that dive to give a better sense of the size of the worms. That Blood Star is about 15 cm long. Photo February 12, 2022.

So TODAY’S mission was to return to this dive site and focus on the interaction between this species of necklace-worm and Short Plumose Anemones. How abundant are they? Are they biting the anemones?Are the worms anywhere other than around Short Plumose Anemones? Are the anemones using their acontia as a defense against the worms? Acontia are defensive strands filled with stinging cells (nematocysts) that are ejected when an anemone is irritated / threatened / stressed. The acontia can extend far beyond the anemone, providing longer distance defense than the stinging cells in an anemones tentacles.

Dive buddy Natasha Dickinson today. This is the exact same spot as what you see in the images from February 12th above. I contrast the two photos at the very end of this blog so you can see how things have changed after 22 days. Of course I do not know how much the anemones would move around in the absence of the worms.


To answer those questions:
– I found the slime tubes almost everywhere there were Short Plumose Anemones at this site. I did not find them anywhere else i.e. this species of necklace-worm’s slime tubes were only around Short Plumose Anemones.
– I only found a few Short Plumose Anemones using their acontia but it seems more likely that they were being used against other anemones. I cannot know if the anemones dislodge themselves as a defense. There were only a few places where there were the circles of slime tubes where an anemone had once been. There were far more places where the slime tubes were in amongst Short Plumose Anemones.
– YES I do believe this species of necklace-worm is biting into the Short Plumose Anemones. See below for abundant photos from today.

Some Short Plumose Anemones using their acontia. See those little white strands?


I will of course provide updates as I learn more via the researchers and other divers / underwater photographers. As always, I hope it is a source of wonder for you to learn more about these species, their adaptations and interactions, AND how much we humans still have to learn about the natural world around us. 🙂


All photos below are from March 6, 2022.

Taking a bite? Also looks like this anemone is about to undergo “pedal laceration” to reproduce asexually.
Here too it looks like some of the anemones are in the process of pedal laceration = form of asexual reproduction.

Below, you can contrast the same spot after 22 days. There has been a lot of change but again, I do not know how much the anemones would move around and/or dislodge in the absence of the worms. Oh no, is this now going to be my life? In addition to trying to document individual Humpback Wales and Tiger Rockfish, now I am going to try to document individual Short Plumose Anemones?! Probably.