Monday, November 11, 2013

The Waters of Howe Sound

What an inspiring sight it must have been for those sailors aboard the surveying ships of the last century as they edged into Howe Sound or numerous other coastal inlets. Many of their impressions have become part of official ship's logs. No doubt there would have been many stories to tell on their return home but unfortunately only of those scenes observed above the waves. But what of the mysteries below? Science fiction writers like Jules Verne had hinted at the possibilities of underwater exploration but only today can we see what wonders are indeed available to us with the help of technology such as SCUBA.

During my University years I was introduced to the environment beneath the surface and to this day I am still amazed at the diversity and formidable beauty that exists there for all who would venture forth. Whenever one wades in from a shore or rolls off the side of a boat there is a door which opens into a new and different world; a world with its own rules, needs and systems.

The cold waters of our Pacific Northwest are full of nutrients brought down by rivers laden with the essential minerals necessary for the growth of microscopic plant life which in turn provides the basis of the ocean food chains. Howe Sound is ,for example, a model for this process. This is reflected up and down our coast in every inlet that has rivers and streams running into it. In our own inlet light from the sun reaches through the shallows to nurture the plants and in every estuary a nursery of new life spills its rich bounty into the endless ebb and flow of the ocean.

Oh yes, oftentimes, a microscope is what is needed to appreciate these small beginnings but many of us find larger "beasties" more exciting. These we do have in Howe Sound, including some creatures of great beauty and size.

As the estuarine bottom life and swimming creatures merge into the bodies of the larger consumers further out in the Sound we see an increasing diversity of form and size which sets the stage for a showcase of underwater wonder. So let us at random visit some of these performers in our play beneath the waves.

Just a few tens of meters below the surface can be seen creatures that are not familiar to the shore explorer and a glimpse of them requires special equipment, both for sustained underwater breathing
and for insulation from our very very cool water. Most divers feel it a great privilege to be able to visit the domain of the largest species of octopus in the world or to play with six foot eels in front of their rocky dens.

As one would imagine, much of Howe Sound's bottom is covered with a thick layer of silt brought down by the river and might seem an unattractive place to pursue the sport of SCUBA diving but it is here that many fascinating creatures dwell. The new diver on his first lesson at Porteau cove may encounter the Dungeness crab which often graces our restaurant table but there are other more exotic forms to behold further out on the current swept rocky reefs and on the craggy spurs which project out from the shoreline. One of the richest spots are the Islands in the middle of the sound such as Pam rocks, Defense Islands and Cristie Islet. Here stalks the giant octopus which can reach a full eight metres span in a mere lifetime of four years. Though they are large and truly awe inspiring to encounter , they are gentle creatures and harmless to man. As a mollusk it is surprising that they have much intelligence. The proportion of their central nervous system to their body mass is the greatest of the animals without back bones. Both octopus and Squid have an ability to change colour in an instant to match their surroundings. It is interesting to note that this ability far surpasses the chameleon. It is also amazing that a mother octopus will guard her eggs in her den without feeding until all are hatched-she will then die of starvation.

Many of the smaller creatures of the reef are adept at camouflage and mimicry . One that particularly comes to mind is the decorator crab which collects pieces of seaweed and shell fragments to festoon his body in order to merge into the background, perhaps avoiding the marauding octopus or prowling rockfish. There are sea-slugs called Nudibranchs which show a variety of forms and demonstrate fascinating survival tricks. With generic names taken from Greek mythology such as Aphrodite, Eolis and Doris. Many steal the stinging cells from sea anemones by eating the owner and incorporating the arsenal into their tissues. In this way they protect their soft bodies from an obvious fate. The giant Nudibranch reaching a length of a foot or more can swim with the grace of a Spanish dancer and may swallow a burrowing sea anemone in an instant. Vulnerable creatures which have soft, unprotected bodies may display warning colours which may be associated with an unpleasant taste or poisonous effect. Patterns of orange and black are common in many Nudibranchs and there is evidence that this does help them discourage would be predators. Some other animals, like the Pacific red Sea Urchins, have a rather more pointed way of protecting themselves!

There are animals which exhibit bizarre behavior in their strivings to escape their enemies. The swimming Scallop is a wonderful example which behaves like a set of snapping dentures when a shadow passes over. This clam has many blue eyes and its two shells will clap together as it seems to purposely swim towards its foe in a threatening manner. Sea cucumbers squirm when faced with the oncoming odor of its arch enemy, the sunflower starfish. And of course it is well known that the octopus sets up its "ink screen" when faced with a real threat.

It is a gift of nature to be able literally to sit and watch these events in the apparent weightless state provided by the physics of immersion, without the artificiality of the aquarium. At every turn one realizes the scope for future research as well as the obvious fragility of the ocean environment. Howe Sound has gone through many traumas over these past years and we hope that there is the beginning of a concerted effort towards conservation in our area. Life forms which I have observed to have been waning in numbers over the past ten to fifteen years, appear to be actually on the increase again. However, one cannot be certain of the reasons without some further scientific investigation. Lingcod have been on the decline and the Fisheries did bring in some recent control measures. These may be working, as many of my diver friends have reported more sightings. They are much smaller than they used to be but let us hope that we can return to the state of twenty years ago when 50-60lb specimens were common here.

It is also interesting to watch the territorial behavior of this species particularly during the winter breeding season. The male guards the clutch of eggs until they hatch and will even lunge toward a diver if he/she gets too close. They have a set of very sharp teeth which has convinced me to respect any fish over ten to fifteen pounds. Their Latin name is Ophiodon which means snake-tooth! Many other species of fish abound in the area; some large like the Salmon or the five foot Mud Shark and some very small like the Bullheads, Gobies and Blennies. Some are more colourful than others but each has some unique quality that only has to be noticed to be appreciated. all you have to do is be patient and pause a while. Some of my best dives were when I remained still or almost still in a very small area rather that rushing about and thereby using up valuable air too quickly. For example, on a dive on Boyer Island reef a couple of years ago I observed a deep sea variety of fish known as a Lancet fish that had come up from the deeper regions . This fish was about six feet long ,snake-like, silver and had a sail resembling a Marlin. It also had long thin sharp teeth. What if I had been swimming too fast and had missed this one!

Never let it be said that there is not beauty in our own underwater backyard- a beauty which rivals some tropical areas. There is a garden like quality to some of our reefs which sport huge sea anemones reaching height of 3-4 feet. Some, like the White Plumose Anemone, form ghostly groves, resembling Grecian columns, standing majestically in the current. They are deceptive in one sense since they are armed to the hilt with thousands of sting cells all ready to paralyze their prey.
These seductive snares will later digest their meal at leisure. Other relatives of the anemones called sea pens, feed in the same way but are orange and get their name from a feather-quill appearance.

Close by there is so much to see, worth preserving. Here in the Sea to sky country we have immeasurable, growing, living fascinating resource; the value of which, we are only beginning to realize. Let's keep learning. 

Jellyfish Bloom in Howe Sound November 2013

                                                 
It has been noticed that recently there has been a bloom of Jellyfish in Howe Sound near Squamish. Many have been seeking an explanation.

 This is the Moon jellyfish (Aurelia). It feeds on any floating organic matter which can range from decaying flotsam such as the left overs from fish like our pink salmon, pollution from humans like sewage, to natural seasonal plankton. They are common all up our coast, including pristine waters.

Their population is greatest in the fall where they are found feeding on the phytoplankton/zooplankton bloom. However the plankton bloom can be especially high where there is an extra amount of suspended organic matter in the water. And yes their population can increase with an increase in water temperature. Remember that we have had an unusually warm summer and fall temperatures this year....They are in greatest numbers in the fall rather than in the spring because of the higher ocean lag temperature..... So the reason is complex and may or may not be a cause for alarm, given all these factors!

We are not always the culprit and nature has still lots of checks and balances. She/he has been at it for a very long time.