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

Posts tagged ‘kelp forest’

Ode to Algae

Ever feel like you want to drift away for a while?
Here you go, a slideshow featuring my photos of kelp and other seaweeds/algae.

Maybe watch it while listening to your favourite calming songs?

I put this slideshow together for an upcoming workshop on seaweed. It’s full, but you can sign up for alerts about future workshops.

Photos are from near northeast Vancouver Island taken by yours truly in the Traditional Territories of the Kwakwa̱ka̱’wakw (the Kwak̕wala-speaking Peoples). Final photo of me photographing kelp is by dive buddy, Don Gordon.

The Importance of Algae
The Ocean’s algae, from the microscopic to the giant kelps:

  • Produce at least 50% of the Earth’s oxygen.
  • Another result of their photosynthesis is that they absorb very significant amounts of carbon dioxide – a very significant climate-changing gas.
  • The algae / seaweeds are producers, converting sunlight to food to fuel the food web. They offer we humans so much nutrition too.
  • Kelps are habitat for hundreds of species.

Kelp in Trouble
Where every species lives is, of course, because the conditions are right. For example, the temperature is not too cold. It’s not too hot. It’s just right. Yes, this is referenced as the Goldilocks Principle. Changing temperatures are impacting the health of kelp forests, as are other variables involved with climate change such as more frequent and stronger winds ripping away more kelp.

Also, there are far fewer Sunflower Stars due to Sea Star Wasting Disease which is believed to be associated with climate change. Sunflower Stars are predators of Green Urchins. Green Urchins graze on kelp. With less Sunflower Stars, there are more Green Urchins. More urchins leads to more grazing on kelp. In the extreme, this leads to “urchin barrens” where the kelp forest has been grazed away. This is not the urchins’ fault, of course. It’s due to human activity.

Less kelp = less food, oxygen, habitat and buffering of carbon dioxide.

Common Solutions:
This is not an additional problem! There are common solutions for many socio/environmental problems. What is going on with kelp is another symptom of the same negative forces – disconnect, a focus on short-term economies, and a culture that perpetuates fear, misinformation, overwhelm and reduced empowerment. Whatever you do to reduce carbon dioxide (from your energy use, consumerism, to how you vote) will help the kelp and all that depends on them. 💙


Amber Forest

Sob! I am having a moment.

The photos you see here are from the new exhibit “Seaweed: Mysteries of the Amber Forests” at the Shaw Centre for the Salish Sea. Those are my kelp photos. 💙

I am choking up at typing that. I have never seen my photos printed that big and am massively moved that they are part of this education aimed at increasing awareness and action for algae.

Mayor Cliff McNeil-Smith cutting the Bull Kelp stipe to open the exhibit yesterday 🙂 .
In green – friend and Director of Exhibits & Engagement, Leah Thorpe.
On right, Executive Director of the Centre, Pauline Finn. On left, Director Allan Lane.

Also featured is the art of Josie Iselin. She scans seaweeds with her flatbed scanner and then often places the photos atop historical images from when that species of seaweed was first described.

Executive Director Pauline Finn pointing to some of Josie Islelin’s art.

I am so grateful to Leah Thorpe, Director of Exhibits & Engagement, for all of her work to make this real.

I have NOT seen the exhibit in person but am now strangely compelled to go to 9811 Seaport Pl, Sidney, southern Vancouver Island. How about you? Show me photos when you go?

You will be thrilled to see there are also some my Find the Fish challenges in the exhibit but in BIG photos WITH answers. 🙂

Yep, choking up at seeing this. That’s my photo associated with all this vital messaging.

How to Help the Kelp, and Why?
The Ocean’s algae, from the microscopic and to the giant kelps:

  • Produce at least 50% of the Earth’s oxygen.
  • Another result of their photosynthesis is that they absorb very significant amounts of carbon dioxide – a very significant climate-changing gas.
  • The algae / seaweeds are producers, converting sunlight to food to fuel the food web. They offer we humans so much nutrition too.
  • Kelps are habitat for hundreds of species.

Kelp Is in Trouble
Where every species lives is, of course, because the conditions are right. For example, the temperature is not too cold. It’s not too hot. It’s just right. Yes, this is referenced as the Goldilocks Principle. Changing temperatures are impacting the health of kelp forests, as are other variables involved with climate change such as more frequent and stronger winds ripping away more kelp.

Also, there are far fewer Sunflower Stars due to Sea Star Wasting Disease which is believed to be associated with climate change. Sunflower Stars are predators of Green Urchins. Green Urchins graze on kelp. With less Sunflower Stars, there are more Green Urchins. More urchins leads to more grazing on kelp. In the extreme, this leads to “urchin barrens” where the kelp forest has been grazed away.
Less kelp = less food, oxygen, habitat and buffering of carbon dioxide.

Green Urchins grazing on kelp.

Don’t Despair!
This is not an additional problem. It’s another symptom of the same problem. Whatever you do to reduce fossil fuel use (from consumerism to how you vote), will help the kelp and all that depends on them.

May the knowledge motivate, not lead to fear and paralysis which perpetuates the problem. It truly is the case that if you are not contributing to solutions, you are part of the problem.
Care more. Connect more. Consume less.

Finding Fish at the Exhibit! ☺️

The exhibit “Seaweed: Mysteries of the Amber Forests” will be at the Salish Sea Centre for about a year.

See my other blogs about the importance of kelp at this link.


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:

Regarding the farming of kelp, please see the Hakai Magazine article at this link which also includes a video from kelp experts about “Kelp Farming: Promises, Pitfalls, and What We Still Don’t Know”.

https://hakaimagazine.com/…/banking-on-the-seaweed-rush/

Holdfast

Have you wondered about what holds down an underwater forest?
It’s the holdfast.

I spent the majority of a recent dive in a sun-soaked Bull Kelp forest. My hope was that the photos I took would communicate the role of the holdfast AND the stunning beauty of being in such forests.

Kelp does not have roots. Rather the algae / kelps get their nutrients through the fronds (leave-like structures) and it is the holdfast that anchors kelp onto rocks.

It’s  a tangle of woody structures that you may have seen washed up on the beach.

Holdfast found on the beach.

You can imagine how strong the holdfast has to be to withstand the buoyancy of the waves, current and the kelp’s floatation (the gas-filled pneumatocysts). The two photos below show how the buoyancy is greater than the mass of the rocks whereby the rock cannot anchor the kelp. 

If rocks are too light to counter the floatation of the pneumatocyst and/or the force of waves and currents, the kelp will change the ocean bottom by carrying away those rocks. You might see these holdfasts, still attached to the rocks, when they wash ashore.  

Friend in the forest – Janice Crook. Second buddy on this dive was John Congdon
Green Urchins climbing up the stipe of Bull Kelp where they will feed. Not a problem when there are enough of predators like Sunflower Stars and Sea Otters. It’s a big problem is there are not enough predators as then too much kelp is grazed away leading to “urchin barrens”.

There you go – a daily dose of depth for you. 

It may be that knowing about holdfasts and their rocks is of particular value in these stormy times.

Holdfast dear readers. Holdfast.

The canopy of the Bull Kelp forest.

Added January 2024, research into the age of holdfasts.

My additional blog items on kelp include:

What on Earth is “Alternation of Generations”?

Late season Bull Kelp forest near Telegraph Cove.

Have you ever wondered how it can be that Bull Kelp forests largely die off in the winter but then reappear in the spring?

Have you ever wondered about the light patches in the fronds of Bull Kelp as seen in the four images below?

I hope that’s enough of a hook for you to want to know more about the remarkable reproduction of most algae / seaweeds (and ferns and mosses).

Their reproduction involves two versions of the same species. The parent generation looks nothing like their offspring but DOES look like their great-offspring’s generation i.e. there is alternation of generations.

Those light patches in the fronds of Bull Kelp are known as as sori (singular is sorus). They most often drop to the bottom of the ocean, release spores which create a completely different, very tiny version of Bull Kelp (asexually) which then makes the big, long version of Bull Kelp (sexually).

Below you have my attempt at further explaining this aided by a really good graphic.

And for the super science nerds (I see you), more detail from Wernberg et al regarding reproduction in kelp forests: “Recruitment involves multiple microscopic stages (i.e. gametophytes and juvenile sporophytes). Because the sperm has to find an egg, male and female gametophytes must settle in close proximity at densities of ca. 1 square millimetre in order to secure fertilization (Reed, 1990). Gametophytes and microscopic sporophytes can persist in the kelp forest understory for weeks to months, where they serve as a ‘seedbank’ (Hoffman & Santelices, 1991). Microscopic sporophytes start growing once stimulated by high light (Reed & Foster, 1984) .  . . Recruitment into the adult population takes anywhere from a few months to 2-3 years depending on the species and local conditions (Pedersen et al, 2012, Teed, 1990). Most juvenile plants succumb to predation, stress, or self-thinning within the first year, but some individuals can remain viable for years without growing (Sjotun, Christie, & Helge Fossa, 2006) until space and light become available.” 

But wait, there’s more. Research from Ulaski and Konar (2021) and others showed that Bull Kelp has an alternate life history strategy. Occasionally, the sori release embryonic sporophytes! These embryonic sporophytes can directly develop (on the blades / fronds) into the large version of Bull Kelp again without going through the free-swimming sexual reproduction phase. The percentage of spores vs. embryonic sporophytes released from sori ranged from 0 to 100% and did not seem to be influenced by (1) if the sori came from overwintering or first generation Bull Kelp; and (2) if the sori came from Bull Kelp that was drifting or attached to the bottom (substrate).

From the abstract of the research paper: ” . . . embryonic sporophytes were occasionally released alongside viable spores. Though embryonic sporophytes were released from sori as early as spring, it was not evident that they were bound by seasonal or spatial limits. The percent of propagules that were embryonic sporophytes ranged from 0% to 100% but were not significantly different between first generation and overwintered adults, nor were they different between attached and drifting individuals. Nevertheless, the characteristic of directly releasing embryonic sporophytes from adult sporophytes might have ecological advantages for N. luetkeana.”

And you thought your sex life was complicated! 🙂

Note that of the giant kelp species found off our coast from California to Alaska, Bull Kelp (Nereocystis luetkeana) is an annual whereby most sporophytes die off every year. Giant Kelp (Macrocystis pyrifera) is perennial whereby the sporophyte does NOT die off at the end of the growing season.

If you have read to this point, congratulations! You are amongst the few humans who may have a good comprehension of alternation off generations. You know what is in the photo below.

Spore packet in the frond of Bull Kelp that washed up on the beach. It always makes me smile to see them while diving, knowing that they will make the forest grow anew. 
The “tear” is where a spore packet has fallen away.

You also know how it can be that Bull Kelp forests reappear in the spring. They were never really gone. The species was there all along, but just in a different version  / generation.

With regard to growth rate, the stipe (stem-like structure) of Bull Kelp can grow up to a maximum height of 36 m. The stipe would have to grow an average of 17 cm a day to reach this length in the 210-day growing period (Druel).  If you include the growth of the fronds (the leaf-like structures), the maximum growth rate has been documented to be at least 25 cm per day (Duncan). Giant Kelp grows even faster and bigger = up to 30.5 cm at day to heights of 53.4 m.

Do know that there is concern about diminishing kelp forests due to impacts of changing ocean conditions  / climate change  / Sea Star Wasting Syndrome. Some sea star species are recovering but the Sunflower Star is not whereby there are more of their prey, including urchins which graze on kelp forests.

Sporophyte of Bull Kelp photographed in summer.  That’s the time of year when the Ocean is all the more soupy with life. It means that the more typical photos of beautiful kelp forests are difficult to obtain because the water is thick with gametes, phytoplankton, larvae and other zooplankton. Bu this is the time of year that the kelp forests are at maximum productivity – as habitat, food, oxygen producers and carbon dioxide absorbers. When it is colder, there is better visibility because there is less sunlight for phytoplankton growth and reduced cues for reproduction of marine invertebrates.

The two mages below are from the Beaty Biodiversity Museum via Bridgette Clarkson.

Sources: 

More good sources to understand alternation of generations:

Bull Kelp in January.

Enough Carbon Monoxide to Kill a Chicken ?

If you live on the West Coast, you may have heard someone say . . .   “There’s enough carbon monoxide (CO) in Bull Kelp to kill a chicken”.

Recently, while teaching a marine naturalist workshop, I was asked if this was true. And oh what a rabbit hole this took me into, leading not only to chickens, but elephants! Actually, just one elephant but it’s a whole menagerie of facts. You’ll see.

I knew that carbon monoxide is a byproduct of respiration in some brown algae like Bull Kelp (Nereocystis leutkeana). I also knew that carbon monoxide is one of the gases found in the float-like structure called the “pneumatocyst”, keeping the kelp buoyant so that the fronds can better photosynthesize, nearer to the sun. The stem-like structure, the stipe, is also hollow and directly connected to the pneumatocyst and, thereby, must contain some carbon monoxide too.

However, I had never checked if the amount of carbon monoxide could indeed be measured by the official scientific unit of “chicken killer”.

The fact-finding mission took me all the way back to 1917 and the research of Seth Langdon who discovered that there was carbon monoxide in Bull Kelp and then exposed the concentration to various animals. And yes, he killed chickens. So it’s true.

But it gets even more interesting.

Bull Kelp float (pneumatocyst) and fronds. ©Jackie Hildering.

Jump ahead to 2013 and the Masters thesis of Lauran Liggen. How thrilled I was to learn from her work that, not only is there enough carbon monoxide in Bull Kelp to kill a chicken – there’s enough to kill an adult man (don’t worry, she did not use Langdon’s lethal methods to prove this).

Specifically from her research: ” Earth’s atmosphere contains only a small amount of CO (~0.000025%) whereas pneumatocysts contain an average concentration of 1.6%  . . .  A study conducted by Landgon (1917) determined whether or not the concentration of CO was at a toxic level by exposing pneumatocyst gases to animals and measuring their physiological effects. Subsequently, the statement familiar to most phycologists [cool people who study algae], that the pneumatocysts of Nereocystis have enough CO “to kill a chicken” was a product of Langdon (1917). Without harming any animals, data collected during this study can further support this statement. 1.6% CO is a potentially toxic amount given that concentrations of CO greater than 100 ppm (0.01%) could kill or render a person unconscious (Suner et al. 2008). Given that an average adult male has a lung capacity of 5800 ml and the largest recorded pneumatocyst in this study (725 ml) had a CO concentration of 1.6%, if an average sized man inhaled the gas inside the largest sampled pneumatocyst, then in one breath he would ingest 1500 ppm of CO, 15-times greater than the maximum concentration a person could tolerate before passing out.”

Wow. Just wow. That’s a lot more than one chicken.

So where does the elephant come in? 

While trying to source the chicken and Bull Kelp story, I came across the following about Bull Kelp in the book “Pacific Seaweeds” by super phycologists, Louis Druehl and Bridgette Clarkston: “Ronald E. Foreman, in pursuit of his PhD (University of California, Berkley, 1970), discovered that the float, which may have a volume of up to 3 litres . . . has carbon monoxide, an infamous poison as one of its buoyancy gases. Some years ago LD [Louis Druehl] had the opportunity to test the herbivore’s ability to detect the kelp-packaged carbon monoxide. While teaching a seaweed course for the University of Alaska, [he] shared an apartment complex with Bo, a circus elephant [say WHAT?!] and once presented Bo with an entire fresh bull kelp. Bo’s response was to yank the plant from [his] hands (poor table manners) and eat the blades. Then, to Louis Druehl’s surprise, Bo stomped on the float, releasing the gas before he ate it. Does this behaviour suggest elephants once lived in association with kelp and learned to avoid the poisonous gas?”

Let me answer that. No! This is a sample size of ONE with a circus elephant who lived in an apartment complex in Alaska. This may not have been the wildest of elephants but possibly a pretty wild apartment complex. 🙂

Can’t make this stuff up and it’s great to be able to report that naturalists didn’t. Those who have been saying “Bull Kelp is kept afloat with enough carbon monoxide to kill a chicken” are right. In fact, they’ve been low-balling the amount. However, I would suggest that there is more valuable messaging around Bull Kelp and its great importance as habitat, fuel for the food web, oxygen production and carbon dioxide absorption.

And once again, with this blog, I feel like I have fulfilled part of my calling by providing essential, factual, life-enhancing information. In this case, involving kelp, chickens and an elephant named Bo.

You’re welcome.

Note: The genus for Bull Kelp, “Nereocystis”, is Greek  for “mermaid’s bladder”.

For more on Bull Kelp, please see my additional blogs:

Sources:

All photos in this blog ©Jackie Hildering.

Into the Forest

Submerge into the forest with me.

Escape for just a little while.

Immerse into the beauty. Feel the fragility?

Know your connection and reliance and . . . embrace the humility of it all.

Hoping these photos from today’s dive in a Bull Kelp forest provide you with all of that.

For more on the importance of kelp forests, please see the posts at this link. 

Down we go.November sun streaming into the Bull Kelp forest and . . . trees above the surface.
©2018 Jackie Hildering.

 

Split Kelp, Striped Sunstar and female Kelp Greenling. See her (orange fish)?
©2018 Jackie Hildering

 

Blood Star, Crimson Anemone, Pink Soft Coral, Giant Plumose Anemones, etc!
©2018 Jackie Hildering

 

Striped Sunstar just below the surface.
©2018 Jackie Hildering

 

Crimson and Giant Plumose Anemones (with a school of rockfish in the background).
©2018 Jackie Hildering

 

Proliferating Anemones on the stipes of Split Kelp and on a species of coralline algae.
©2018 Jackie Hildering.

 

Lingcod in the forest.
©2018 Jackie Hildering.

 

Northern Kelp Crab climbing in the Bull Kelp Forest.
©2018 Jackie Hildering.

 

And . . . following my bubbles to the surface, sun refracting through the Bull Kelp. Back to the terrestrial part of our world so reliant on the Ocean’s algae for the production of oxygen, buffering of carbon dioxide and as fuel in marine food webs. 
©2018 Jackie Hildering.

Every Breath You Take . . . .

XX

Er – sorry about that. Thanks to the blog title, you likely now have The Police’s stalker-ish lyrics playing annoyingly in your head.

Let me take the Sting out of that for you.

The only lines of the song that apply to this blog item are: “Every breath you take” and “Every move you make” because  . . . this blog is about marine algae.

giant kelp DSC06372

Fronds of kelp ©Jackie Hildering

Yes, that’s right – marine algae; the plant-like material of our oceans that ranges in size from the phytoplankton that give the NE Pacific Ocean its emerald colour and soupy richness, to the giant kelp species that provide habitat as ocean forests.

Breathe in.  A conservative 50% of the life-sustaining oxygen in that breath came from marine algae.

These organisms are also attempting to scrub away the devastating impacts of our fossil fuel addiction, photosynthesizing carbon dioxide into oxygen and serving as carbon sinks.

Bull Kelp Forest

One of the images that started it all. ©Jackie Hildering

Life on earth simply could not survive without marine algae and this conclusion is valid even without considering their role as the basis of ocean food webs (and recognize that an estimated 50% of all species on earth are marine).

Why then, while we seem to have some understanding of how dependent we are on the terrestrial plants living up here with us, do so many of us appear to be ignorant of the vital importance of the marine algae that inhabit 71% of the earth’s surface?

Bull kelp forest in current © Jackie Hildering

Bull kelp forest in current ©Jackie Hildering

Why are we seemingly not as driven to save marine algae from the impacts of pollution as we are to stop deforestation? Is it that damn illusion that land is separate from sea?

Or, somewhere deep within or briny beings, do we feel a connection?

I have experience that suggests this might be the case.

It’s an accidental discovery . . . I never really planned to become an underwater photographer. Having the great privilege of living in this beautiful place, initially I focused largely (quite literally) on photographing big marine mammals. I was using charismatic megafauna to try to inspire conservation.

© Jackie Hildering

But then  . . . I was gifted an underwater camera and quite early on, I started photographing kelp.

For me, kelp is the entry point into the marine world into which I love to disappear and its beauty has long intoxicated me. In fact, I have a kelp forest tattooed on my lower left leg!

But never, ever could I have anticipated the way the images would be received by non-divers. They have proven to be vital tools in “taking” people underwater with me and I believe no whale image I have taken has done as much to engage, create wonder, appreciation and, hopefully, respect and positive action for what lies below the surface.

© 2012 Jackie Hildering-5121314

Sun streaming through bull kelp forest ©Jackie Hildering

Why are these images received as they are?  Many answers are possible from a pure aesthetic appreciation of kelp’s form and colour to the fact that kelp forests are literally at the surface, recognizable but submerged in mystery.

But, maybe, just maybe there’s a deep connection born out of knowing that we are dependent on marine algae for every breath we take.

And that – gives me hope.

For more kelp images, please click here for my gallery.

Note: Seaweeds, kelp and phytoplankton photosynthesize but are (most often) not classified as plants. They are algae. For an explanation of the classification, distinction and scientific debate, see:  “The Seaweed Site – “What are algae?” 

Below the Kelp

It’s the day before summer begins and  . . . what a day it was.

We had radiant sunshine and a flat-calm ocean during our dive today.

I can think of no better way to share the beauty and wonder of today’s adventure than to take you below the kelp with me.

Please see today’s images at link below. I have included captions that provide a bit of information about the species we were so fortunate to see.

Come below the kelp – by clicking here.

Journey Through Kelp

Bull Kelp is so beautiful, especially now in the early spring when the young “sporophyte” stage is growing at an insanely fast rate. The stipe (stem-like structure) of this kelp species, Nereocystis luetkeana, 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). 

The growth rate of the stipe and fronds together (the leaf-like structures) has been documented to reach an average of 25 cm per day (source: Duncan). 

Baby bull kelp

Baby Bull Kelp

It is at this early stage of growth too that Bull Kelp is an intense colour green unlike anything else I know. When older, the colour darkens to an olive green. 

Kelp is an alga, not a plant. However, like plants, algae also photosynthesize, converting the sun’s energy into food. Algae have simpler structures and different chemical pathways than plants.

Young Bull Kelp grows so fast to allow the leaf-like parts, called “fronds”, to be closer to the sun so that more food can be made.  

Sun streaming through a Bull Kelp forest.

The round, floating part of the kelp, is the “pneumatocyst”. This bladder-like structure is completely hollow and is filled with carbon monoxide (NOT carbon dioxide), allowing the long fronds to drift at the surface to catch the sun’s rays. 

Apparently, there is enough carbon monoxide in Bull Kelp to kill a chicken! Now that’s valuable information. See my blog “Enough Carbon Monoxide to Kill a Chicken” at this link. 

The stipe is also hollow. I’m sure it is not what Nature had intended, but this allows we humans to play the stipe of Bull Kelp like a trumpet or didgeridoo! The stipe gets thinner and whip-like near the holdfast which is why Bull Kelp likely got its name because the stipe is shaped like a “bull whip”.

Bull Kelp does not have roots. Rather it is a “holdfast”, a tangle of  woody structures, that anchors Bull Kelp onto rocks. However, if rocks are too light to counter the floatation of the pneumatocyst, the kelp will actually change the ocean bottom by carrying away smaller rocks, likely ending up washed onto the shore. 

Bull kelp holdfast. No roots.

Bull Kelp holdfast. No roots. See my blog on holdfasts at this link. 

Bull Kelp always grows in patches, truly forming an underwater forest that is life-giving for the same reasons as terrestrial forests: kelp forests buffer the climate change gas carbon dioxide; produce oxygen; and provide food and habitat for so many other organisms. Bull Kelp forests are, in fact, estimated to provide habitat for some 750 species of fish and invertebrates (animals without backbones).

Sea urchins are one of those invertebrates, living in the forest and grazing on a lot of Bull Kelp. If Sea Otters, Mink, Wolf-Eels and other predators of urchins did not keep urchins in check, there would be further reduced kelp forests. Sea Star Wasting Syndrome has devastated the world’s largest sea star species, the Sunflower Star (Pyncopodia helianthoides) which is a predator of Green Urchins. This has led to too many of these urchins and an increase in the number of urchin barrens. Please see my blog here for information on urchin barrens and Sea Star Wasting Syndrome. 

Kelp forests are not what they used to be for reasons far beyond our foolishness in over-harvesting Sea Otters. There used to be such dense forests that it is theorized “Ancient humans from Asia may have entered the Americas following an ocean highway made of dense kelp.“

All coastal boaters still benefit from kelp. It is a navigational aid since, where it grows, you know you there is shallower water.

We divers have yet an additional reason to value kelp.  Since it is so strong,  we can hold onto it if we need to during our safety stop (3 minutes at 5 metres depth) or if needing to gradually pull ourselves down into the depths or back to the surface.   

Oh – and you can eat it. (I love pickled young Bull Kelp!) 

And yes, you could do puppet shows with Bull Kelp, cutting a face into the bladder like you would into a jack-o-lantern. The fronds even look like two pig-tails! 

THEN there is how Bull Kelp reproduces. The offspring look nothing like their parents. Please see here for my blog on the remarkable phenomena that is “alternation of generations”. 

But for now, come underwater with me. Come into the forest, breath in, breath out and worship the kelp!

My additional blog items on kelp include:

Sources: