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Decorator Crabs! The best-dressed in the NE Pacific Ocean.

Are you ready? I’ve been collecting these photos for a long time. Now, finally, I think I have enough to deliver this marine fashion show to you – the best dressed of the NE Pacific Ocean!

Decorator crabs are camo-crabs. They pluck bits of life from their surroundings and attach it to themselves. AND, if their surroundings change, they change their outfit.

Graceful Decorator Crab covered with hydroids including the “Raspberry Hydroid” which was only recognized as a new species in 2013 with the area near Telegraph Cove (Weynton Pass) being one of the few areas these colonies are known to live. ©Jackie Hildering.

This is highly functional fashion. Not only does this covering of life allow the crabs to hide from potential predators, it also apparently changes the way the crabs feel and taste in a way that deters their predators. Sponges taste bad or are even toxic to many predators and animals like hydroids and other “cnidarians” have stinging cells. Thereby, if you cover yourself with sponges or cnidarians, predators be gone!

Indeed, even though decorator crab species look like walking gardens, often what they attach are not algae but other animals – hydroids, sponges and bryozoans.

Additional bonuses of carrying other organisms on your back may be:

You have potential snacks within a pincher’s reach.
Your camouflage allows you to get closer to your prey.
You are carrying weapons!

From A Snail’s Odyssey: “Apart from passive camouflage from potential predators, other functions of the behaviour may include disguise for closer approach to prey, and provision of tools for active defense, such as a branches of hydroids containing functional stinging cells or pieces of sponges or tunicates containing toxic chemicals.”

Graceful Decorator Crab with snippets of sponge attached to his/her carapace (Hooded Nudibranchs in the background). This individual realized it had been seen and switched to the defence strategy of looking big since “so many fish predators are limited by the size of their mouths” (Source: Crabs and Shrimps of the Pacific Coast); ©Jackie Hildering.

Note too that not all growth on the back of crabs is the result of decorating and remember that crabs moult, crawling out the back of their shells in order to grow. Also from A Snail’s Odyssey: “In some cases these camouflagings result from settlement of spores and larvae . . . . Passive buildup of growths is greater with increasing age as moulting frequency decreases. Also, in many species there is a final or terminal moult which, if the species’ exoskeleton is receptive to settlement of larvae and spores, leads to an even greater build-up of cover.”

Graceful Decorator Crab adorned with (and atop of) Glove Sponge. ©Jackie Hildering.

“Spider crab” (superfamily Majoidea) species are the ones that most often adorn themselves. From Greg Jensen‘s Crabs and Shrimps of the Pacific Coast: “Many spider crabs . . . mask themselves with algae or encrusting organisms so that they can hide in plain sight. The decorator crabs are equipped with curved setae much like the hook part of Velcro fasteners: after shredding material a bit with their mandibles, they press it into place. The largest species tend to stop actively decorating once they outgrow most of their predators.”

Crab predators include the Giant Pacific Octopus and fish species like Cabezon, some rockfish, Surfperch, Wolf Eel and the Staghorn Sculpin. Of course, at low tide, birds and mammals are also predators.

Hoping this adds to the wonder, connection and respect for our marine neighbours. Enjoy the rest of the show!

[For research on decorator crabs with great diagrams explaining how how attachment occurs see this link.]

Try not to smile!

Another Graceful Kelp Crab adorned with Raspberry Hydroids.

Here you can even see where the Graceful Decorator Crab has clipped off bits of sponge. AND s/he’s in the act of attaching clippings. ©Jackie Hildering.

Longhorn Decorator Crab. ©Jackie Hildering.

Heart Crab (I THINK) – not likely to have decorated itself but rather this is the result of the settlement and accumulation of organisms = a walking ecosystem. ©Jackie Hildering.

Graceful Kelp Crab with adornment of Sea Lettuce. ©Jackie Hildering

Graceful Decorator Crab in front of a Painted Sea Star. S/he had just moved from being camouflaged among kelp to moving in front of the sea star. ©Jackie Hildering.

This Graceful Decorator Crab has adorned him/herself with bits of Barnacle Nudibranch egg masses for camouflage. You can see the egg masses behind the crab.

Decorator crab species in the NE Pacific Ocean include:

Graceful Decorator Crab – Oregonia gracilis
Graceful Kelp Crab – Pugettia gracilis
Longhorn Decorator Crab – Chorilia longipes
Other species too will sometimes put a bit of camouflage on their rostrum e.g. Northern Kelp Crab – Pugettia producta

Sea Angels and Sea Butterflies?!

My dry suit has been hosed down and is drying in the sun; my regulator is soaking in fresh water; the washing machine is chug chug chugging with the clothes used over the last days of diving; and my head and heart are full of so much I want to share.

I’m back from another trip organized to God’s Pocket Dive Resort just beyond Port Hardy . . . more than 11 hours spent underwater over the last days. Such an escape. Such an immersion in wonder and that sense of humility that comes with submerging in the force that sustains this planet. Such an opportunity to learn.

I saw my first Sea Angel.

My buddy and I had been drifting along for about an hour. We had schooled with rockfish; hung next to Orange Sea Pens as they bowed in the current; and marvelled at the abundance of anemones and their babies, studding the forests of kelp. We had done our safety stop with a seeming snowfall of pulsing Aggregating Jellies streaming down around us in the sun’s beams.

Thousands of Aggregating Jellies aka Umbrella Jellies. Eutonina indicans to 3.5 cm across. Collective noun for jellies is "smack". ©2016 Jackie Hildering.

Thousands of Aggregating Jellies also known as “Umbrella Jellies”. Eutonina indicans to 3.5 cm across.
Collective noun for jellies is “smack”. ©2016 Jackie Hildering.

Close-up on Aggregating Jelly aka Umbrella Jelly. Eutonina indicans to 3.5 cm across. ©2016 Jackie Hildering.

Close-up on Aggregating Jelly – Eutonina indicans to 3.5 cm across.
©2016 Jackie Hildering.

We had already been further awed by Sea Butterflies “flying” by our masks. Sea Butterflies are planktonic sea slugs! They are “pteropods” – swimming shell-less molluscs whose “wings”(ptero) are their feet (pods). This genus does have an internal gelatinous “pseudoconch” (false shell) and the brown dot you see in my image is the gut. Sea Butterflies feed by forming a mucus web up to 2 m in diameter in which they trap smaller plankton and bits of organic matter. Oh to see that. It was apparently first documented in the 1970s by researchers while SCUBA diving.

Sea Butterfly - Corolla spectabilis. Dark spot is the gut. ©2016 Jackie Hildering.

Sea Butterfly – Corolla spectabilis. Dark spot is the gut. See this link for more species information and a video (with excited diver vocals) of a swimming Sea Butterfly.

All those jellies and Sea Butterflies pulsing around us and then, just when I was about to break the surface back into the world where gravity has such a stronger hold on me, I saw it! So small, tiny wings pulsing . . . a Sea Angel!

Image #1 of the Sea Angel – Cliopsis krohni to 4 cm long. Also known as a “Sea Cherub”.
©2016 Jackie Hildering.

Image #2 of the Sea Angel. ©2016 Jackie Hildering.

Image #3 of the Sea Angel. ©2016 Jackie Hildering.

This is another species of planktonic, “winged” sea slug (but the adults of this species are completely shell-less; they do not even have pseudoconch). Sea Angels are a rarity so far to the north and are only occasionally seen at the surface (found to depths of 1.5 km). Their presence is likely due to warmer waters (El Nino and possible climate change) and a big northwest wind that had raged a couple of nights prior. The wonder of it, to see something so otherworldly, to know of its rarity in this area, and to get a sense of its planktonic fragility – surviving from a larval stage, escaping predation by fish, and to be carried by the currents in the vastness of the sea.

It may be hard to imagine but this species is a voracious predator! Cliopsis feeds on other planktonic snails by grabbing them with a long proboscis (which can be up to two times its body length), a sharp radula and hooks made of chiton!

Screen grab from the "Plankton Chronicles" showing a Sea Angel feeding! See amazing 1.5 min clip here http://planktonchronicles.org/en/episode/pteropods-swimming-mollusks/.

Screen grab from the “Plankton Chronicles” showing a Sea Angel feeding!
See amazing 1.5 min clip at this link.

And yes, their diet includes Sea Butterflies. Sea Angels can eat organisms up to three times their size!

When a Sea Angel comes into contact with a Sea Butterfly’s feeding web, it reels it in, dragging the Sea Butterfly with it. When close enough, the Sea Angel then uses its probosis to “cut” the Sea Butterfly from its psuedoconch and eats it.

The marvel of it all, the delicate balance of this planktonic world about which so few of us have knowledge but which can be so impacted by our activities. There is concern about the impact of ocean acidification (caused by our carbon use) on the development of these organisms.

As always, don’t be despondent. See the beauty, know your connection, and recognize the common solutions and great gains of caring more . . .. and consuming less.

And They Spread Their Giant Wing-Like Fins . . .

TMD Memes.001

And they spread their giant wing-like fins . . . and returned from the brink.

The whales remind us of our great capacity for positive change . . . when our value systems change and knowledge, connection and humility replace fear and misunderstanding.

The simple solution? Care More. Consume Less.

There are still so many ways to indirectly kill a whale and damage the life-sustaining seas upon which we all depend.

Image is of “Jigger” the mature female Humpback Whale who breached for 18 minutes. More images below.

You simply can’t be the same after seeing something like this, nor would I want to be.

What triggered this behaviour may have been an encounter with another Humpback (“Slash” BCX0177″) but we cannot know for sure.

For the work of our Marine Education and Research Society, please see here and yes, you can support our work by sponsoring a Humpback Whale!

Remarkable Giant Pacific Octopus + Wolf Eel Encounter

Trust me, you are going to love the video below!

Giant Pacific Octopus passing over a mature male Wolf Eel in his den. See video below. ©Jackie Hildering

It is one of the most remarkable encounters I have witnessed in all my dives.

It’s a fortunate enough thing to be able to watch a large Giant Pacific Octopus when it is hunting. In this encounter, the octopus passes directly over a mature male Wolf Eel in his den. THEN, a Decorator Warbonnet emerges as well.

It was an exciting day in this wonderful marine neighbourhood.

I hope this 3-minute clip allows you to share in the awe and excitement.

For me, this was the NE Pacific Ocean equivalent of seeing a giraffe, elephant and rhino in close proximity.

Video and photos contributed by dive buddies Katie Morgan and Diane Reid while on our trip with God’s Pocket Dive Resort.

For more information on Wolf Eels (including that they are not an eel at all), see my previous blog here.
For more information on Giant Pacific Octopuses, click here for previous blogs and here for a blog specifically on hunting in Giant Pacific Octopus.

Underwater Smoking Log and the Worm That is Not a Worm?

Submerging into the dark, you never know what you are going to see.

It is a large part of what is so intoxicating about diving in cold, dark waters – all the mystery; all the wonder; all the opportunity for learning and sharing.

So what was it today?

This – a smoking log at about 6 m depth!

Teredo navalis spawning. March 8, 2015 ©Jackie Hildering.

Northwest Shipworms spawning. March 8, 2015 ©Jackie Hildering.

The “smoke” was brief but intense and of course it was not smoke at all. It was the spawn of some animal. Many marine invertebrates are broadcast spawners where all individuals in an area release their sex cells at the same time to enhance the chances of fertilization.

I knew the source of the “smoke” had to be a shipworm species since it was coming from a rotting log with lots of tunnels bored into it. I then had to do a bit of reading to be sure of whether it was the invasive Naval Shipworm (Teredo navalis), or the indigenous Northwest Shipworm (Bankia setacea).

Either way, shipworms are not worms at all!

Northwest Shipworm Source: MARINE WOOD BORERS IN BRITISH COLUMBIA; D. B. Quayle; 1992

Shipworms are saltwater clams. They look like a worm in a calcareous tube but have two small shells at the front of their bodies that are specialized to bore through wood, much to our dismay! The clams also have symbiotic bacteria that release an enzyme to help break down the cellulose in the wood.

I believe in this case it was the Northwest Shipworm that was spawning and the initial cue for the synchronous release of sex cells in this species is believed to be a sudden change in temperature or salinity. Once the spawn begins, it is believed that neighbouring Northwest Shipworms drawing water into their siphons detect the spawn and that this further triggers them to release their sex cells.

The Northwest Shipworm it is more common in BC than the Naval Shipworm; the tunnels in the wood looked like those caused by this species; but also relevant in my knowing it was this species is that I saw eggs being released as well as sperm.

With the oh-so-successful Naval Shipworm that originated in the Atlantic but is now boring through wood in all the world’s oceans, only the males release sex cells. Sperm are then drawn into females’ inhalant siphons; the eggs are fertilized and develop in the female’s gills in huge numbers to be released as free-swimming larvae.

Northwest Shipworms spawning. The white material on the logs is known as “frass”- waste discharged through the clams’ excurrent siphons. March 8, 2015 ©Jackie Hildering.

The Northwest Shipworm does not have this reproductive strategy. With both genders broadcast spawning, you can imagine how many sex cells need to be released for successful reproduction.

After about 3 weeks (at 12 – 15°C), the Northwest Shipworm larvae appear to be able to detect wood. They attach themselves, soften the wood, bore into it, develop into adults and cause economic discontent in we humans. This is especially the case in the logging industry which depends on transporting and storing wood in the Ocean.

Apparently the Northwest Shipworm can burrow 10 cm per month at temperatures greater than 10°C. See here for examples of the damage to wood by this species. If you are a Northern Vancouver Islander, you can see how this wood has been used as a decorative wall covering in the Whale Interpretive Centre.

For me, there was no discontent today. It was a wonder to be swimming by at the exact time this species was spawning. Providing me with a further opportunity to . . . smoke out facts about our marine life and share them with you!

Gentle Giants. What to do when you find your dive buddy with a Giant Pacific Octopus on her head.

Please note, I have shared our experience below to reduce the misunderstanding and demonization of octopuses NOT to stimulate diver attempts at interactions. What is described below was an unsolicited gift experienced by those with a very high level of dive experience; knowledge of octopuses (and dive buddy) behaviour; and solid safety protocols.

The Kraken?! Devilfish?!

Scary?! Dangerous?! Alien?

Suggest such things about a Giant Pacific Octopus to any scuba diver respectful of marine life who has had an encounter with one of these gentle giants, and there is going to be a very strong response shattering such mythology.

As it always goes, fear and mythology thrive where there is absence of knowledge.

Any negative encounters between divers and Giant Pacific Octopuses that I am aware of, result from divers manhandling them “insisting” on an encounter, or involve octopuses that are habituated as a result of being fed by humans.

Giant Pacific Octopus, Copper Rockfish and dive buddy Natasha Dickinson.
Read about this remarkable encounter below. ©2015 Jackie Hildering

We, as divers, are so fortunate to come across Giant Pacific Octopuses in their world where they are invertebrate royalty. We are able to meet them on their turf, and thereby know how inquisitive and intelligent they are. We know they are mighty, highly adaptable predators.

And, we know too, when we look into their eyes, that observation and assessment is being reciprocated.

That preamble was necessary before sharing what happened today.

This did . . . .

1. Dive buddy Natasha Dickinson during the remarkable Giant Pacific Octopus encounter.
See the Copper Rockfish too? ©2015 Jackie Hildering

I had been taking photographs of Lingcod males guarding their egg masses and noted that my dive buddy Natasha Dickinson was signalling me with her light, indicating that she had found something of particular interest.

I took a few more shots and then swam towards her and found . . . my dive buddy with a Giant Pacific Octopus completely covering her face. Sorry that I missed that shot. I was so in awe of what I saw.

Natasha is an incredibly skilled and experienced diver with a deep respect for marine life. She was clearly not afraid, nor was the octopus.

Natasha had taken the precaution of putting her hand over the regulator in her mouth in case the octopus took an interest in that but otherwise, allowed her to explore.

I would learn later that, while waiting for me she had been watching the Copper Rockfish that you will see in all but one of the photos in this blog. This rockfish stuck very near the octopus. A buddy? That I don’t know but escorting a Giant Pacific Octopus on the hunt is a really good strategy. As the octopus flushes out animals from under rocks with his/her arms, the rockfish can grab the prey that do not end up under the octopus’ mantle.

While observing the rockfish, the Giant Pacific Octopus had slowly advanced toward Natasha and she remained where she was, intrigued at what would happened and having a contingency plan.

When I started to take photos the Giant Pacific Octopus gradually backed away but had taken a particular interest in a clasp at the end of a bungee cord on Natasha’s gear.

You can see how her arm was entwined around the cord and how there was some flashing of white in the skin. You can also see the Copper Rockfish!

I believe this octopus was a female, thanks to feedback I received from self-admitted Cephalopod Geek supreme, Keely Langford of the Vancouver Aquarium. Octopus males have a “hectocotylus arm”. In Giant Pacific Octopuses, it is the third arm on their right. The hectocotylus stores the spermatophores – packets of sex cells, two of which are handed over to a receptive female who stores them until ready to fertilize her eggs.

Having the good fortune to get photos of the right side of this octopus, particularly #5 and #7, allowed me to see that the top of third arm on the right is not differentiated and that therefore, this was a female.

Back to recounting our adventure . . . .

After about a minute or two of gently tugging on the bungee cord, Ms. Giant Pacific Octopus let go.

Natasha swam a bit further off, allowing me a few minutes to marvel and photograph this beauty – the Giant Pacific Octopus AND the Copper Rockfish.

When Natasha circled back, the octopus flashed a bit of white as you can see in the image below. Recognition?

We both found ourselves waving goodbye when we, regretfully, had to return to our terrestrial world.

So what to do when you find a Giant Pacific Octopus on your dive buddy’s head? Observe, marvel, take some photos, share and maybe it can help dispel some of the mythology and vilification about these fabulous marine neighbours.

12.. Eye-to-eye with a gentle giant. My peering into a Giant Pacific Octopus’ den earlier this month (using a macro lens). ©Jackie Hildering

Giant Pacific Octopus Facts:

Enteroctopus dofleini is the world’s largest octopod species with the maximum records for size being 9.8 m from arm tip to arm tip and 198.2 kg.
Average life expectancy is only 3 to 4 years.
Like other octopuses:
- They have a beak with venom, three hearts, blue blood, and their skin is capable of detecting chemicals (as our nose does).
- While many sources report their having 9 brains, octopuses only really have one donut-shaped brain positioned around their oesophagus and then each of their eight arms has many neurons, this is referenced as “distributed intelligence”. Damir Allen explains at this source; “Think of it like a command centre and 8 independent soldiers. They all act semi-independently, and if separated from the main body they will continue to capture food and try to deliver it to a non-existent mouth.”
- Their ink is not just a distraction for predators but contains the chemical tyrosinase which causes eye irritation and messes up the predators’ senses of smell and taste.
- They are jet propelled and are capable of incredible camouflage where they can not only change the colour of their skin but also its texture to blend in with their surroundings.
- They mate only once. From the Vic High Marine website regarding Giant Pacific Octopuses: “Females die directly after they have finished laying and guarding to their egg however males live a slightly longer time. Octopus reproduction starts when a male uses a specialized tentacle [sic, octopuses have arms not tentacles] to pass two spermatophores (sperm packages) to the female. Once given the sperm the female stores the package until she is ready to fertilize the eggs. Before a female is ready to fertilize the eggs she has to find a suitable den. This search can take the future mother up to one month! Once the perfect place is found the female shuts herself in using rocks. From there she fertilizes each egg and gathers them in bundle of approximately 200. She hangs each group of eggs from the ceiling of the cave. This is a long process because, on average, a female octopus can lay up to 50,000 eggs. The incubation time for octopus eggs are six and a half months. During this time the female stays in the cave, not even leaving to eat, attending to the eggs by constantly blowing oxygenated water on to them. When the baby octopuses hatch they are referred to as paralave. These tiny juveniles swim up to the surface joining other zoo plankton and spending weeks feeding on tiny phytoplankton. Once they have developed enough mass they descend to the benthic zone. As for the mother, she waits until all the eggs have hatched then emerges from the cave and dies shortly afterwards due to the starvation she endured during the months she spent devoted to tending her eggs.“
Excellent on-line resources on octopuses.
- A Snail’s Odyssey – Learn About Octopus. Includes excellent information on reproduction in Giant Pacific Octopuses.
- Berkley – The Cephalopoda – Squids, octopuses, nautilus, and ammonites. Includes an explanation of why octopuses have “arms” (non-retractable) not “tentacles” (retractable).
- http://scubadiverlife.com/2014/01/15/the-giant-pacific-octopus/
Best book on Giant Pacific Octopuses – The Giant Pacific Octopus and Other Cephalopods of the Pacific Coast by James A. Cosgrove and Neil McDaniel.
And the plural really is “octopuses” not “octopi”! See #3 at this link if you are doubtful.

Great thanks to Gwa’sala-‘Nakwaxda’xw Marine Services for making this dive possible.

Media coverage so thankfully resulting from this blog includes:

Earth Touch News; 2015-02-26; “What to do when an octopus gives you an eight-armed face hug“
Global News TV interview (video); 2015-02-25 – “Encounter with a Giant Octopus“
Global News; 2015-02-25; “WATCH: Local diver’s encounter with a giant octopus goes viral”
Huffington Post; 2015-02-24; “Giant Octopus, Diver Encounter Shows Nature Of ‘Gentle Giant’: Biologist“
CTV News TV interview (video); 2015-02-24; “Gentle hug from octopus“
CTV News; 2015-02-24; Deep-sea hug: Giant octopus wraps around diver’s face near Vancouver Island

Otherworldly Drifter. Mind Blown.

Today was the first time ever that, while diving, I made a gesture to my dive buddy indicating that my brain had exploded.

We weren’t deep; the remarkable find that had me awestruck was at 3 to 5 metre depth. It’s a known species and is found throughout the Atlantic, Pacific and Indian Oceans but . . . . it’s certainly extremely rare here around NE Vancouver Island and it is SO otherworldly.

Let me take you on a short journey of discovery.

I was already pretty excited when I found the organism in the photo below. I knew it to be a salp “aggregate” and was delighted that there was an amphipod hitchhiker. See it?

Cyclosalpa bakeri with amphipod hitchhiker ©Jackie Hildering; www.themarinedetective.ca

Cyclosalpa bakeri with amphipod hitchhiker.
©Jackie Hildering; http://www.themarinedetective.ca

Salps are such unique gelatinous animals! They belong to the group of highly evolved invertebrates known as tunicates. Most tunicate species live attached to the bottom when they are adults but salps remain Ocean drifters for their whole lives. Because of their gelatinous “tunic” they have even been referred to as Ocean Gummy Bears.

Their reproduction is totally otherworldly! They alternate between two forms. The image above is of the “aggregate” form or “salp chain” that, dependent on species, can be made up of millions of individuals. The aggregate form reproduces sexually to form a barrel-shaped solitary form. The solitary form buds off (asexually) to produce the individuals that make up the aggregate form and so on! Salps apparently grow faster than any other multicellular organism! (Source: JelliesZone).

Back to the dive . . . so I was already pretty thrilled to have seen the salp chain of this unique species and was taking the photo below of an Alabaster Nudibranch (because you can NEVER have enough photos of Alabaster Nudibranchs) . . . .

Alabaster nudibranch. Dirona albolineata to 18 cm aka “white-lined dirona” or “frosted nudibranch”. ©2015 Jackie Hildering

. . . . and then I saw something hovering above me, zeppelin like.

Brain exploded. WHAT was this?!

Pelagic tunicate. Salp species - Thetys, solitary phase. To 33 cm. ©2015 Jackie Hildering

It was about 25 cm long.

It had openings on both ends.

It clearly had internal organs.

And it had unique projections on what I assumed was its back end.

The look on my dive buddy Natasha Dickinson’s face in the image below says it all!

Dive buddy with Thetys. ©2015 Jackie Hildering

I was pretty sure that it was the solitary form of some species of salp but . . . so big?

As soon as I got home I grabbed my copy of Wrobel and Mills’ “Pelagic Coast Pelagic Invertebrates” and emailed a few photos of this unique find to Andy Lamb, co-author of Marine Life of the Pacific Northwest.

Ahh – it’s wonderful to have friends in deep places. Andy came back very quickly with the ID. It was a salp indeed, in fact, the world’s biggest. Thetys* in the solitary form can grow to 33 cm!

From Dave Wrobel’s The JelliesZone webpage: “Thetys is truly an impressive member of the zooplankton. It is the largest species of salp along the West Coast and is relatively easy to distinguish from all others. Unlike most gelatinous animals, the body is relatively firm due to the thick spiny test (the test, or tunic, is the hard outer covering typical of many tunicates, hence the name for the group). It retains its shape even when removed from the water. Solitary individuals have 20 partial muscle bands . . . that are used for constricting the body while pumping water for feeding and locomotion. A pair of pigmented posterior projections are very distinctive, as is the darkly colored, compact gut . . . Like other salps, Thetys continuous pumps water through a mucous net to extract phytoplankton and other small particles. Although relatively uncommon in Monterey Bay [and therefore very uncommon so much further north where I sighted this individual], this widespread species can be found in temperate and tropical waters of the Pacific, Atlantic and Indian Oceans, to depths of about 150 meters.”

I was intrigued how an animal that lives in the open Ocean and depends on plankton could be so big?

How could it filter enough plankton out of the water?

I came upon research from MIT (2010) that revealed how salps could get enough nutrients to be so big and fast growing. Their mucus nets are astounding in how they are able to trap incredibly small-sized plankton. With this find, the researchers referenced salps as “the vacuum cleaners of the ocean” and confirmed how important they are because of what they do to huge volumes of climate-changing carbon.

In the Oceanus Magazine article Salps Catch the Ocean’s Tiniest Organisms, the researchers explain “As they eat, they [the salps] consume a very broad range of carbon-containing particles and efficiently pack the carbon into large, dense fecal pellets that sink rapidly to the ocean depths, Madin said. “This removes carbon from the surface waters,” Sutherland said, “and brings it to a depth where you won’t see it again for years to centuries.” And more carbon sinking to the bottom reduces the amount and concentration of carbon in the upper ocean, letting more carbon dioxide enter the ocean from the atmosphere, explained Stocker” [thereby reducing the amount in the atmosphere where it impacts climate.]

I of course also hoped to find a good photo or video of the salp chain of this species (the aggregate form) and came upon this 1-minute clip by Patrick Anders Webster (taken off the coast of central California).

Wow!!! Mind-blown again.

And below, an additional video from Patrick from May 2016, also off the coast of California.

[*You may have noticed that the full scientific name for this tunicate species is Thetys vagina as assigned by the German naturalist Wilhelm Gottlieb Tilesius von Tilenau in 1802. Likely at that time, “vagina” did not yet have its anatomical meaning and the species name was chosen for the Latin origin of the word meaning “wrapper” / “sheath”.]

Further information:

Scripps zooplankton guide – https://scripps.ucsd.edu/zooplanktonguide/species/thetys-vagina

Jelly Zone – http://jellieszone.com/pelagic-tunicates/thetys/

Thank Goodness for Second Chances . . . .

It’s Canadian Thanksgiving and I am overwhelmed with depth of gratitude and purpose.

It is an extraordinary privilege to be able to live the life I do and I want so much for it to count.

Thank you dear readers for helping to amplify the beauty, mystery and fragility into the world so that there may be more understanding that there is no divide between land and sea and how our daily actions regarding chemical and energy use connect us – no matter how far away from this place you are.

The photo below is from two days ago – “Frosty” the Humpback Whale in Johnstone Strait, NE Vancouver Island.

To think we could have lost these glorious, majestic, mysterious, winged, singing, acrobatic ambassadors of our life-sustaining seas . . . .

Thank goodness for second chances.

Frosty the Humpback Whale (BCX1187) in Johnstone Strait, October 11, 2014. Just outside Telegraph Cove. Blinkhorn Light in the background. ©Jackie Hildering.

Sea of Love – Broadcast Spawning!

Most often, divers prefer good visibility. But oh to have the good fortune to happen to be in the water when marine invertebrates are spawning!

I’ll never forget the first time the seas suddenly turned white and these green packets drifted by my mask.

I was euphoric that I happened to be in the water when Orange Sea Cucumbers (Cucumaria miniata) and Giant Plumose Anemones (Metridium farcimen) were broadcast spawning. Witnessing the magnitude of this great force that ensures these species will survive is as awe-inspiring as witnessing the annual spawn of herring or salmon.

Female orange sea cucumber about to release an egg pellet. Click to enlarge. © 2014 Jackie Hildering; www.themarinedetective.ca

The same female orange sea cucumber 1 minute later, releasing the egg pellet. Click to enlarge. © 2014 Jackie Hildering; www.themarinedetective.ca

Another spawning male. Orange sea cucumbers can also be this darker colour. Click to enlarge. © 2014 Jackie Hildering; www.themarinedetective.ca

During broadcast spawning, invertebrate males and females each release their sex cells into the water column – in astoundingly copious amounts.

You can imagine how many gametes must be released for there to be a chance of fertilization and for enough of the resulting larvae to survive and not to be eaten by the many filter feeders such as barnacles, anemones and sea cucumbers!

Not only was it the male Orange Sea Cucumbers that were making the cloudy with their astounding numbers of gametes. The Giant Plumose Anemones were broadcast spawning too. Males releasing slow, white jets of their sperm and females then releasing their pinker egg masses. (Note that Giant Plumose Anemones can reproduce asexually as well by pedal laceration but broadcast spawning allows for diversity through sexual reproduction). [Update 2017: Photos added showing contrast between male and female gamete “packages” with thanks to Neil McDaniel for confirming the pink masses are eggs.]

Spawning giant plumose anemone. Click to enlarge. © 2014 Jackie Hildering; www.themarinedetective.ca

Giant plumose anemone releasing gametes. Click to enlarge. © 2014 Jackie Hildering; www.themarinedetective.ca

It is of course a good strategy to have males and females living in close proximity and that timing is everything! The spawn must be synchronized. To release sex cells when others of your kind are not doing so, would be a very failed reproductive strategy indeed. Probable cues for spawning are ocean temperature; the number of days/hours of sunlight (cumulative temperature); and/or the presence of a plankton bloom.

Apparently for both Orange Sea Cucumbers and Giant Plumose Anemones, the males are the first to release their gametes, triggering the females to spawn.

Research has also found that, in the case of Orange Sea Cucumbers, females release around 130,000 eggs packaged in buoyant egg pellets. The egg pellets drift to the surface and dissociate into the individual eggs after about 20 minutes. Spawning in orange sea cucumbers most often happens within 1.5 hours after slack low tide which adds to the success by allowing for a greater concentration of sex cells, maximizing the chances of fertilization.

Through these images, I hope I have been able to relay the awe I felt at witnessing this biological marvel that has allowed these species to survive on Earth for thousands of times longer than we humans have walked upright.

Female Gumboot Chiton spawning. Click this link for video and more information.

Attack of the Sea Slugs!

[Update March 2018 – There has been a reclassification of this species of nudibranch whereby Hermissenda crassicornis is also being referenced as the “Thick-Horned Nudibranch. Please see my blog at this link for that information.]

This is an Opalescent Nudibranch (Hermissenda crassicornis).

Opalescent nudibranch. The white batch is a colony of animals known as kelp-encrusting bryozoan. © 2014 Jackie Hildering; www.themarinedetective.ca

Here is one climbing giant kelp with hooded nudibranchs in the background.

Opalescent nudibranch © 2014 Jackie Hildering; www.themarinedetective.ca

I know! Aren’t they astonishingly beautiful? Opalescent Nudibranchs are one of the most powerful ambassadors for shattering the misconception that warm waters are home to more colourful life. They truly help in raising awareness about the incredibly exotic and vibrant life hidden just below the surface in the dark, rich, cold waters of the NE Pacific.

But they help with something else too.

I recently received a video clip of Opalescent Nudibranchs from Tavish Campbell, taken while with Pacific Wild documenting the life that would be at risk if tanker traffic came to Caamano Sound. Tavish, who is a fellow-diver and appreciator of all things marine, asked, “Hey Marine Detective, what’s going on here?!” What I saw led me to realize how this species is also a very powerful engager for addressing another default notion we humans seem to have.

We tend to bestow judgemental labels on animals depending on our interpretation of their beauty. We are inclined to think beautiful animals are “nice”, “cute” and “benign”, and foreign looking animals are “mean”, “ugly” and/or “bad”.

While I appreciate that some organisms may be more aesthetically pleasing than others, there is no “ugly” in Nature and there certainly isn’t “bad”. Organisms look and live as they do because it works. Their appearance and behaviours are the result of expanses of time longer than we humans, as newcomers, can truly appreciate. Organisms’ adaptation allow them to survive and fulfil their niche in Nature’s puzzle so that there is the greatest chance of balance. [Insert “God” instead of “Nature” if this is your preference.]

Therefore, for example, there are no “bad” kinds of orca but rather orca populations whose job in Nature is to eat other marine mammals. There are dolphins that sometimes kill other marine mammals without this being for the purposes of food (no matter how much this conflicts with the “Flipper-like” identities we have imposed on them). Sea otters do things that definitely are NOT cute and . . . it also means that beautiful sea slugs will also do what they need to in order to survive.

I take such comfort in not needing to judge Nature. It just is. In contrast, human behaviours too often do NOT enhance the potential of balance in Nature or even the chances of our own survival.

So here’s the jaw-dropping video. Ready . . .?

Opalescent Nudibranchs in all their beauty, are extremely voracious predators and, as is evident in the video, will also attack their own kind. Reportedly, fights most often result when the animals come into contact head-to-head. The animal closest to the head or end of the other has the advantage of getting in the first bite and thereby the greater likelihood of killing their opponent and eating them.

But, they are hermaphrodites, they need one another to mate! As hermaphrodites, there is not even male-to-male competition for females! So why, when your chances of finding a mate as a sea slug are already pretty limited, would you kill another of your kind instead of mating with them?

I hypothesize that it would have to do with the balance between needing to eat and needing to mate and/or that there is some sort of genetic competition going on. That’s all I got. Insert rap awe and wonder here. I may not know why they do what they do but I do know, there has to be an advantage to their survival.

What I also know for sure is that this gives a whole new meaning to “slugging it out”!

Opalescent nudibranch egg mass. http://jackiehildering.smugmug.com/Underwater/Sea-slugs/

Opalescent Nudibranch egg mass. Every species of nudibranch has distinct egg masses i.e. they are species specific. 2014 Jackie Hildering; http://www.themarinedetective.ca