Deeper Waters

Adam Taylor’s Close Encounters of the Octopus Kind

by Adam Taylor

My first encounter with an octopus in the wild was nearly 30 years ago and I remember it clearly. It was a cold day in late winter with fresh snow blanketing the North Shore Mountains. We were on our first open-water training dives off the Bowen Lodge/CNIB dock in Kwilákm. Our scuba instructor was islander Brian Hartwick, a marine biology professor who ran the Scientific Diving Program at Simon Fraser University. He was an octopus researcher and his familiarity and comfort level with octopus would help encourage my budding fascination with the ocean.

We followed Brian past colourful sea stars, urchins, and other creatures of the deep. Within a few minutes, Brian directed us to a large boulder and motioned for the first buddy pair to gently lay down on the sandy bottom nearby. He shone his light in a crack under the rock exposing an octopus in its den. Buddy pairs switched places and Brian signaled for us to take turns looking under the rock.

Brian then swam the first group maybe 30 feet away to show us yet another octopus in its den. This one reached out to explore his hand as it rested on the seabed nearby. I was instantly enthralled by this creature. As we were watching it, the octopus, in turn, was watching us through the wide opening in its den. The octopus’ colours and textures changed as it explored Brian’s gloves. I later learned that octopus’ suckers are the only parts of their body which cannot change colour or texture. The suckers are chemotactile, meaning they taste what they touch. One of the ways an octopus explores its world and determines what is edible is through touch. This fact would come into play on numerous future encounters. 

Generally speaking, from an octopus’ point of view, any large animal up in the water column appears as a predator. When I am around an octopus, I gently settle onto a safe spot on the bottom, careful to sit a short distance away and not in the octopus’ direct line of travel. Over the years, I have been privileged to encounter many octopus, and with the exception of specimens hiding in objects collected for interpretive dives or underwater cleanups, the encounters have always been on the octopus’ terms. Interactions with wild animals are unpredictable and should not be sought out. Octopus, however, are highly intelligent and curious creatures and, if they feel comfortable, can initiate an encounter. A giant Pacific octopus is an extremely powerful animal. Divers encountering one should be very careful and only experienced divers should allow an octopus to interact.

Generally red in appearance, octopus have an amazing ability to blend into the background by changing both texture and colour. The most common sign of stress in octopus when they bleach white or flatten themselves on the bottom. When this occurs, it is time to move on and leave the octopus in peace.

Some of my favourite octopus encounters include:

In Kwilákm, three thumb-sized specimens emerged from old bottles collected for beachside interpretation with my niece and nephew’s Kindergarten and Grade 1 classes. One of their classmates, the child of a childhood friend, excitedly but politely interrupted from nearby touch tank while I was showing the kids sea stars “Uncle Adam, Uncle Adam, you even found us octopus!” Thinking he had mistaken a small sea star as an octopus I looked over and sure enough there were three juvenile octopus the size of a thumb exploring the tank.

In Seymour Bay my diving buddy and I encountered a smaller one to one and a half metre GPO out hunting. It was scooping the water facing into the current and appeared to be scenting for prey or a mate. Again, we set down gently off to the side of its direction of travel and, curiosity winning over caution, this octopus made a bee-line for my camera and started exploring it. In addition to gently keeping a low profile in the water column I find the bulk of my camera to create a distraction, especially when an octopus sees its reflection in the lens.

After an initial taste-test of my camera, the octopus disengaged and briefly explored my buddy’s gloved hand. Once it realized nothing was edible, it disengaged again and carried on the hunt.

Wanting to film the hunt, I again settled down off to the side in its direction of travel so it would not be blocked, but the octopus altered course, approached me again and climbed right up on top of my camera and started manipulating the light mounting arms. There I was eye-to-eye with a mesmerizing creature. Gentle colour patterns and flashing around its eye gave me the impression it was thinking or trying to communicate. After seven minutes it disengaged and carried on hunting. As it slid off my camera, I could make out the hectocotylus, or small groove male octopus have on the end of one arm which is used during mating .

We were lucky enough to see it capture a crab at the end of our encounter. While reviewing that footage I noted a small black shape float away from under its mantle. Turns out it stole a small foam float from my camera rig and must have been taking it home to see if it was edible.

Have a look at a video I took in Bowen’s Seymour Bay of a Giant Pacific Octopus on the hunt:

One thing I always found fascinating about octopus was how the good den locations, like a Bowen Island rental, never remain empty for long. Giant Pacific Octopus only live three to five years and in that time grow rapidly from the size of a grain of rice to up to six metres across. This requires a large range of den sizes as they outgrow one location then move into another. Octopi bring captured prey back to the den where they can eat it safely. I’ve been diving local sites for nearly 30 years and there are some dens which are almost always occupied. Those den locations, their size, and the nearby hunting opportunities made them ideal for octopus of a certain size. I often wonder if successive generations have ever utilized the same den.

There is something both beautiful and sad about the devotion of the mother octopus. About 40 days after mating, she attaches strings of small, fertilized eggs (10,000 to 70,000 in total) to rocks in a crevice, or under a boulder, her nesting den. She will spend the last six to seven months of her life gently grooming the eggs with her suckers and blowing water through the string of eggs to help keep the eggs clean and oxygenated until they hatch out as babies the size of a grain of rice. In most cases, the female survives the hatching and lingers in the den for another few weeks before she dies. She has not eaten for as long as 11 months and has lost more than 60% of her body weight. Mother octopus have been known to leave their dens before dying so her body doesn’t attract predators to the eggs.

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Octopus

Two octopus species call the bottom of Kwilákm home: the Pacific red octopus (Octopus rubescens), which can grow to 61 cm arm tip to arm tip, and the Giant Pacific Octopus (Enteroctopus dofleini), which is, by far, the largest octopus species in the world, can weigh up to 50 kg, and span more than six metres.

First Nations stories often portray the octopus as a powerful sea-spirit helper to the chief of the undersea world. The octopus is sometimes depicted as a monster that can devour canoes and even whole villages. The octopus features in the art of healers, perhaps due to its ability to change colour and texture and regenerate lost parts—if an arm is damaged or lost in combat, the part is rapidly repaired or replaced.

Octopi are shy creatures, doing their best to evade predators. Octopi camouflage to avoid detection, changing both colour and skin texture to match their surroundings. If an octopus is certain it has been detected it may jet away, sometimes ejecting ink via its funnel directly at the pursuer.

Active and swift predators, octopi eat a wide variety of invertebrate and fish. In turn, they are eaten by larger fishes and mammals such as seals and humans. They leave the security of their den on hunting trips mostly at night when most visual predators are at a disadvantage.

Click on the photo below to see a video of a thumb-sized, juvenile Pacific red octopus on the prowl, filmed by Bowen diver Adam Taylor:

From a human point of view, octopi seem amazingly put together creatures. They have three hearts: a systemic heart that circulates blood around the body and two smaller hearts to pump blood through the gills where carbon dioxide is given off and oxygen is absorbed. Octopuses use one central brain to control their nervous systems and a small brain in each arm to control movement. They’re also known for having pale blue blood thanks to a copper rich protein called hemocyanin in their bloodstream which is used to transport oxygen.

On the underside, in the centre of the eight arms is the octopus’mouth, containing a horny, parrot-like beak and a radula. The radula is a file-like toothed structure in the mouth—tiny teeth that can drill holes or shred prey.

Other than its beak, the octopus has no hard parts at all, and this enables it to crawl through unbelievably small openings. Giant Pacific octopi (GPO) in Kwilákm learn that crab traps are a potential source of quick and easy food. The octopus crawls into the trap, kills and consumes the crabs, then squeezes its way out of the trap to return to its den where it digests dinner.

The GPO has two rows of 200 suckers per arm and eight arms or 1,600 suckers in total. The largest suckers can reach six cm in diameter and can support about 16 kg each. In theory, the grip of the approximately 1,600 suckers of an octopus spanning less than two metres could have total sucking capacity of almost 13 tons.

Bowen Island SCUBA diver Adam Taylor has spent many happy hours in the company of Kwilákm’s octopi. Learn about Adam’s Close Encounters of the Octopus Kind.

For more about octopus in the Salish Sea: Super Suckers, The Giant Pacific Octopus by James A. Cosgrove & Neil McDaniel, Harbour Publishing. Available to borrow from the Bowen Island Public Library.

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Harbour Seal

(Phoca vitulina)

We are fortunate that we can count on seeing harbour seals in Kwilákm and along the other shores of Bowen Island just about any time of year. If you are a paddler or swimmer, or even just walking along the shore, you will know that these sea dogs are a curious bunch, often approaching to see what we are doing.

Harbour seals are distinctive with half-submerged rounded heads and large dark eyes, and their habit of slipping away underwater nose-last.

During the summer, you may see them hauled out at low tide on a rocky reef just offshore of the large dock at the Bowen Lodge on the south side of Kwilákm.

During salmon runs, seals will congregate near the Causeway, trying to intercept returning salmon.

In January 2019, a large number of adult seals spent a week hunting anchovy in Kwilákm, and young seals were left nearby in a nursery in the shallows by the Causeway.

Harbour seals also congregate in nearby Snug Cove. They use a favorite haul-out rock below the cliffs near the navigation light at the east end of Dorman Point. At times, the Union Steamship Marina has had its own resident seal. One year, a female seal birthed a seal pub on one of the floats in the marina.

Seal coats are remarkably variable in colour and pattern. The background colour can range from cream to grey to black with either dark or light-coloured spots. Adult seals can weigh up to 70 kg, stretch 1.5 m in length, and live 20 to 30 years. They are opportunistic feeders with a varied diet that includes crabs, herring, anchovy, and other fish.

Check out these video links:

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Northern Anchovy

(Engraulis mordax)

Anchovy are a small fish with a huge impact on the overall health of Atl’ka7tsem/Howe Soundand Kwilákm and our enjoyment of nature. If a school of anchovy is nearby, you are sure to know because it creates a spectacle that you cannot miss. All sorts of birds and mammals are in on the feast!

Anchovy are a small (18-25 cm) silvery schooling fish similar to herring, smelt, and sardines that together are referred to as forage or bait fish. Northern anchovy are most abundant further south off the coast of California and Oregon, but southern BC has always been within the northern limit of their range. But since 2015, likely related to a warming ocean, anchovy have become the most commonly observed forage fish in outer Atl’ka7tsem/Howe Soundand around Bowen Island.

Anchovy of all stages of life, except eggs, have been observed in Kwilákm. Anchovy are open water spawners, with females laying their eggs and males fertilizing them with sperm in offshore waters. This spawning is rarely observed.

However juvenile anchovy 2 to 3 cm long have been observed by snorkelers in Kwilákm most summers since 2015.

The summer of 2021 was especially remarkable, with large schools of juvenile anchovy resident in Kwilákm throughout the summer months. Some schools of smaller anchovy 2 to 3 cm long were likely hatched in 2021. Some schools of larger fish, 5 to 6 cm long, were likely hatched in 2020. Cutthroat trout ranging in size from 15 to 20 cm. long were commonly seen hunting these anchovy. The trout swim below the schools, darting up to seize their prey.

But it is the schools of adult anchovy that really create the drama. These schools can be herded into bays and towards shores by diving ducks such as cormorants and merganser, as well as by seals and sea lions. Then a frenzy begins.

Gulls quickly gather to feast on the anchovy school forced up to the surface by the underwater attacks of birds and mammals. Such an event was captured by Bob Turner in his video “Howe Sound Ballet”. While screaming gulls circled above, other gulls plunged to catch anchovy near surface, and seals, a sea lion, cormorants and a merganser attacked from below.

All this time the anchovy school, perhaps 4 metres wide and 3 metres deep, continuously changed shape as fish evaded the attackers but remained as a school.

Anchovy grow to 18 to 25 cm long and can live seven years. They are primarily filter feeders and swim with their mouths agape, straining plankton.

This open-mouth feeding flares the gill covers, causing a circular reflection in sunlight. Aa school of anchovy produce a glittering mass of silver-dollar flashes that distinguishes them from herring.

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Plankton

A breathtaking miniature world of beauty lies hidden beneath the surface of Kwilákm. Plankton are free-floating plants (phytoplankton), animals (zooplankton), and bacteria (bacterioplankton) of infinite form, function, and design.

Some are easily seen, such as jellyfish.

But most are less than a millimetre long. Many can be seen only with the aid of a microscope.

But they can be present in the water in the millions, their bodies colouring the waves and blocking light penetration.

Plankton are of immense ecological importance in Kwilákm and throughout the oceans of the world. Many marine creatures, ranging from other plankton creatures, to anchovies and juvenile salmon, to whales, depend on these tiny plants and animals for food.

Phytoplankton

These microscopic, usually single-celled plants drift in the ocean. They provide essential ecological services, including oxygen production and carbon storage, through photosynthesis. They exist in the billions in the first few metres of the ocean surface, and are the foundation of most marine food webs.

Phytoplankton produce 50% of the oxygen that we breathe.

Watching Phytoplankton

Like land plants on Bowen, phytoplankton in Kwilákm have seasonal growth cycles. Keen observers can see the changes in the colour and clarity of the ocean surface.

In winter, even though storms mix deep nutrient-rich waters with surface waters, the water is too cold, and sunlight is too weak for much phytoplankton to grow. And so, the seawater is generally clear.

In spring, days become longer, the ocean surface warms, and the amount of sunlight increases. These factors, along with the abundance of minerals from freshwater runoff and upwelling from the depths, create ideal conditions for phytoplankton. Although individual plants are too small to see without aide of a microscope, plankton blooms can colour the ocean.

In summer, phytoplankton growth continues and the ocean remains murky, clouded by live phytoplankton and the many small creatures that feed on them. As summer progresses, there are fewer dissolved minerals in the surface water, plankton populations decrease, and the water clears.

Fall winds often stir up the waters, bringing mineral-rich water from the deep to the surface, resulting in fall phytoplankton blooms.

Zooplankton

Zooplankton are animal plankton. They include many bizarre-looking representatives and all major invertebrate groups, including some that can only be found in the plankton.

This group also includes vertebrates such as fish eggs and larvae.

They eat either phytoplankton or each other. Most are microscopic, but some are large enough to see with the unaided eye.

Pacific krill, tiny relatives of prawns and lobsters, are important zooplankton in Atl’ka7tsem/Howe Sound.

In the 1980s, they were so plentiful that there was a short commercial fishery in the Sound. This keystone of the marine food chain was hunted for use in tropical fish food and fertilizer.

Like phytoplankton, zooplankton drift with the currents, and although most can swim, they cannot progress against currents.

Bacterioplankton

These mostly single celled organisms are tiny, ranging in size from 0.5 to 50 micrometres (1×10-6 metre). We can’t see them with the naked eye. Scientists study them using powerful electron microscopes. Bacterioplankton include uncounted species, and thousands may be found in a single drop of water. Almost all are harmless to people. Some bacterioplankton are primary producers, using chlorophyll to convert sunlight into sugar. Most are primary consumers eating dead and dying plankton, mostly phytoplankton.

Studies in Atl’ka7tsem/Howe Sound in the 1980s found that their population follows the annual population cycle of phytoplankton: lowest numbers are in mid-winter, greater in spring, greater again in summer, and greatest in early fall (immediately after the die-off of phytoplankton).

In the local food chain, they are the key food of cloud sponges.

A New Plankton Survey of Atl’ka7tsem/Howe Sound

Since seminal research on the plankton of Howe Sound took place in the 1970’s, there was no further studies on the ecological health of plankton until very recently. As part of the Howe Sound/Atl’ka7tsem Marine Reference Guide, Tides Canada, and the Marine Science Foundation have begun a multi-year survey of plankton in the Sound starting in summer 2020.

This much-needed study will provide baseline population data that may be used in the ongoing monitoring and management of marine food webs in the Sound.

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Some of the sea birds and mammals that venture into Kwilákm are easily overlooked. There are also many creatures that live in the water column and on the bottom that few of us are fortunate enough to encounter. This section features some of the common deep water creatures that live or hunt further from shore.

The deep water of the bay is in direct contact with the mineral-rich salty waters of outer Atl’ka7tsem/Howe Sound. Living here can be challenging. In summer, the upper waters stratify as lighter, sun warmed waters lie on top of dense, colder deep waters. The density differential prevents these layers from mixing. As the summer progresses, phytoplankton use up many of nutrients in the upper layer, starving the plankton, fewer plankton survive into late summer.

Deep waters in Kwilákm exceed 2 metres.

In summer, red tide plankton can be washed in from the Sound and the open waters of the Salish Sea. The toxins they release can poison and sicken fish and other marine creatures.

In winter, the waters change in many ways. The surface can be very rough when the winds come from the east. Wave action mixes the upper and lower levels of the ocean making it a uniform cold as low as 4^oC. As well, winter rain storms swell the freshwater outflow from Terminal Creek, flushing thousands of litres of cold fresh water. The fresh water can rest on the ocean surface until mixed by wave action into the salt waters below, resulting in significant winter dilution of the salt water in the entire bay.

Winter sea birds and year-round resident harbour seals must be adapted to cold rough waters.

At any time of year, predators from outside Kwilákm, such as pods of Bigg’s killer whales, can venture in to hunt seals and sea lions.

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