Tag Archives: oceans

Word for Wednesday: Z is for zooxanthellae.

This week, for my final Word for Wednesday of the series, I could justifiably have gone for ‘zero’, ‘zip’, or ‘zilch’.  That – very frustratingly – was the state of my internet connection on Wednesday, hence the Thursday publication!  Sometimes there is just no way of working to ideals in this country, and you just have to growl in irritation, breathe deeply for a while, give a resigned shrug, then wait!

Anyway, getting back to my actual chosen word!  I thought that, as the alphabet started, way back in July, with ‘albescent‘, it would round things out nicely to close with zooxanthellae.  And if you’ve been with me on my blogging journey for a while now, you will know that I am passionate about our beautiful, fragile seas and oceans.


Zooxanthellae (noun).

(plural of zooxanthella).

  • any of various symbiotic dinoflagellates that live within the cells of other organisms (as reef-building coral polyps)
  • any of various symbiotic yellow-green or yellow–brown algae in the cytoplasm of certain radiolarians and marine invertebrates.
  • Any of various yellow-brown photosynthetic dinoflagellates that live symbiotically within the cells of other organisms, especially certain corals and other marine invertebrates.

Word derivation: modern Latinzoo ‘of animals’ + Greek xanthos ‘yellow’ + the diminutive suffix -ella.

First Known Use: circa 1891.



Beautiful healthy coral, as far as the eye could see. Plus two curious and friendly Batfish, keeping me company on my dive!


Eugene H. Kaplan’s book, Sensuous Seas: Tales of a Marine Biologist is an absolutely fascinating read.  There really is a whole world of wonder going on just beneath those waves.  I also love that Kaplan is an academic and scientist who writes to actually be read and understood by normal people – fantastic!! It’s a book I go back to time and time again.

“Sadly, the astonishing interaction between coral and zooxanthellae is being reversed by modern man.  Global warming does exist.  Proof lies in the sensitive nature of coral reefs.  Having evolved in the constant temperatures of the open sea, corals are unable to stand even brief exposure to fluctuating temperatures. Present-day oceans average 2°C above past normal temperature.  Corals, needing constancy, do not adapt.  In their death throws, they expel their zooxanthellae.  This sensitivity makes corals the canaries in the coal mines.  They warn us of the impending doom of many of the earth’s less flexible organisms. The life sustaining zooxanthellae are being expelled from corals in all the world’s oceans.  The corals, bereft of their internal providers, die.  The condition is called bleaching.  In all the world’s oceans the green and gold colour of many coral reefs is gone, leaving a slimy white coating of dying polyps.”

(Eugene H. Kaplan, Sensuous Seas: Tales of a Marine Biologist).

SO that’s the end of the line.  It’s been such a fun ride from A to Z.  I hope you’ve enjoyed reading these posts as much as I have enjoyed writing them.  I don’t think I fancy just looping round and starting at A all over again though.  But where to next?  Something new and exciting next week!


Slow and steady wins the race.

Anyone who has ever scuba dived should know that there are some basic safety guidelines to follow to ensure every dive is fun rather than frightening.  Scuba diving is not about who gets from A to B first.  The whole scuba experience is intended to be enjoyed safely, and at a relaxed pace.  And that starts and finishes with a suitably slow, controlled descent and ascent.

“Scuba diving is not considered a good exercise for aerobic conditioning. If scuba divers do everything ‘right’, by maintaining neutral buoyancy, drifting with currents, and breathing slowly and deeply while underwater, they should expend less energy than when resting on land.”

(Michael Strauss, Diving Science).

On the way down, a slow descent gives time to address any buoyancy issues and trim niggles with kit, make sure you and your dive buddy are comfortable in the water, and ensure sufficient time for ears to equalise to the increasing pressure of the water.

On the way up a slow, controlled ascent, with appropriate safety stops for the depth and duration of dive, is even more essential.  It allows our body the time to off-gas the nitrogen accumulated during the dive, which if not eliminated from the body, can lead to decompression sickness or nitrogen narcosis.  And it prevents divers from getting lung injuries and potentially very serious complications, caused by ascending with too much air expanding too rapidly inside our bodies.

Diving is a hugely enjoyable sport and a lifelong passion for thousands of people around the world.  But I think sometimes people overlook that it is also known as an extreme sport for a reason.  The safety rules and guidelines come from years of testing and proven experience. You ignore them at your own peril.

Yet so many people seem disinclined to bother with safety stops at the end of a dive.  Have they become blasé about the risks they are taking, like drivers who drink and then drive? Do they think they look cooler by skipping the safety stop? Do they feel pressurised by others they dive with, to adopt their bad habits? Have they not dived with enough consideration of their air supply to enable them to take the extra time?

If you are a recreational scuba diver because you like diving (and if you don’t like it – well, really, why do it?!) then safety stops should be part of every dive.  The final cherry on the cake.  An extra added bonus.


A good friend, counting off the minutes…

Safety stops are done at shallow depths.  That is usually where the water is warmest, there’s often lots of life to look at, and coral reefs, kelp forests, even the vast deep blue look at their sparkling sunlight best.  Air consumption is slower here than at greater depths, so you can take your time to look around you.  Just enjoy the sensation of floating, weightless in the water, before you have to get back on dry land or the boat, and start the de-kitting process. What’s the rush?

That’s not to say that every safety stop is a gently relaxing end to a dive.  I have spent more than one, swept into a horizontal position, clinging with white knuckles to a descent line dropped by the boat.  Divers above and below me, all of us looking like flags fluttering in the wind as the ripping currents surged past us, trying to pull the regulators out of our mouths. Exhilarating and wild.  Certainly memorable!

I have never skipped a safety stop.  Ever.  Even after hundreds of dives I’d rather take the slow road.  If I’m up on deck five minutes after everyone else, so what?!  Plus, I have seen some incredible things on safety stops that feel like a pay-off for playing it safe.  Some of the most memorable ones?  Eagle rays skimming past in the blue and then hanging around to give us a five minute acrobatics display, turtles swimming right up to check me out, being mobbed by a swirling silvery mass of curious trout.

A handful of minutes, some potentially unforgettable moments to experience, that final chance in a dive to connect with the ocean.  And that safety stop just might save your life.  Slow  and steady really does win the race when it comes to scuba diving.

Happy World Oceans Day!

Today is the 22nd World Oceans Day.  An annual event, celebrating the world’s oceans.  Everything they – and the marine life and landscapes they contain – bring to our life.

And they're off! Green turtle hatchlings, heading off into the sunset on Lankayan, Malaysia.

And they’re off! Green turtle hatchlings, heading off into the sunset on Lankayan, Malaysia.

As a child I literally could not walk along a beach without ending up waist-high in water.  I just couldn’t resist the allure of the waves.  It would start with my shoes and socks coming off.  Then five minutes later I’d roll my trousers up.  Then the trouser legs would be jammed up as high up my thighs as they’d go and I’d wade in a little deeper.  And then in the end I’d just accept the inevitability of soaking wet clothes and go for it. Happy memories.

These days I retain that childlike thrill when I’m walking along a beach or splashing by the shore.  I still can’t help but take my shoes and get my feet wet.  But, as a scuba diver, I also have a deeper love and respect for what lies beneath the waves.  I’ve seen some spectacular underwater sights, sat watching sunsets on some magnificent beaches, been in the company of some inspirational marine conservation champions, and shared some incredible moments with special people whilst under or out on the waters.  I hope for many more magical memories for the future.


Research vessel for the Thresher Shark Research and Conservation Project, Malapascua, Philippines…some of the most interesting and rewarding weeks of my life spent with the team on this scientific study.

I feel so passionately about our oceans.  They are a gift and should be cherished as such.  But as a global population, we take so much from our oceans, put such a burden on them, and give so little back in return.  The World Oceans Day website gives some great suggestions for easy ways to get involved in preservation and protection of our oceans, as well as fun ways to share your love of the oceans with others.

Two of my particular favourites are their ‘wear blue, tell two’ concept and the beach cleanup.

The beach clean-up idea is pretty self-explanatory.  Visit your favourite beach, get your friends and family or local community involved, and do as much as you can to collect and remove the rubbish you find.  But this doesn’t have to be a big all-or-nothing once a year thing.  Make sure that every time you go down to the beach you take away your own rubbish.  And grabbing a few other bits of rubbish you pass on your way to the nearest bin or recycling point is easy. Not only will it improve the appearance of the beach and prevent marine debris, it will make you feel good and at the same time will encourage others to do the same.

‘Wear blue, tell two’ involves you wearing an item of blue clothing, asking people if they know why and then sharing two facts with them about the ocean, or two ways that they can play their part in ocean conservation and protection.  Then ask them to take their turn in ‘wear blue, tell two’.

So here is my little shark warrior all dressed up in blue, and I am assuming that – because you are attentive and nice like that – you would like to ask her why if you could!  So I’ll answer on her behalf!  And because I’m crazy in love with our marine world, I’m going to be generous and give two facts about the ocean AND two ways you can play your part!


Baby shark warrior!

Fact 1: Fish like to stay healthy and look their best, and there are certain species of fish – collectively known as cleaner fish – which help others in their preening.  And the cleaner fish benefit by eating the parasites, dead and diseased tissue that they remove from the client fish.  Cleaner fish set themselves up at a ‘cleaning station’, offering services to bigger fish which under normal circumstances would happily consider such little fish a tasty morsel.  There is a gentleman’s agreement between the cleaner and the client, which is indicated by the client positioning themselves in a certain way, changing colour, or moving in a specific way which indicates that they are there to be cleaned rather than to eat! I am utterly transfixed watching cleaning stations in actions when I spot one when I’m on a dive.  They are amazing examples of fish behaviour.

If you found this interesting then I can highly recommend Sensuous Seas: Tales of a Marine Biologist by E.H Kaplan, which is a fascinating and easy read, even for a non-scientist like me!


Fact 2: In explaining the saltiness of the oceans, there is a myth that they were made salty all at once.  In fact, ocean salts built up over thousands of years to reach today’s levels.  Today, salinity levels in our seas and oceans are relatively stable. And we have learnt how to use that salty water to our advantage. There are more than 4,000 factories around the world removing the salt and changing it into fresh water.  These factories are mostly in the Middle East and other regions where rain and other fresh water sources are scarce.

This fact is taken from Wonders of the Sea by Kendall Haven.  Another fantastic and very engaging book, including some very interesting myths and legends from around the world.


To do your bit to make a difference you can….

  1. Reduce plastic.  Try to use less plastic bags and packaging in general. Take reuseable canvas shopping bags with you when you go food shopping; don’t bag each individual item in a plastic bag.  Recycle.
  2. Eat sustainably.  Think about how sustainable the fish in the supermarket, fish monger or restaurant is, before you buy it.  Avoid fish or seafood which you know is overfished, or which is not sustainably fished.  It can be pretty confusing at times though can’t it?!  The Marine Conservation Society has a great online resource – http://www.fishonline.org/ – to help you make sense of the good, the bad and the ugly when it comes to making sustainable fish buying choices.

I hope you liked the suggestions, and might think about using them.  Perhaps you already do?  Or maybe there are other ways you try to make a difference, in which case I would love to hear them.

I totally understand that it sometimes feels that global conservation efforts and wildlife initiatives can seem overwhelming.  Even a tad futile in the face of the huge difficulties to be overcome.  I know that’s how my husband and I felt when we first moved over from the UK to South East Asia and realised the scale of the shark-fin sales market here.  But all we can all do is do our bit and keep trying.

Just during the three years we have been here the shift in international attitudes about shark finning has been incredible.  And the market for shark fin is noticeably in decline in some areas now, which is a massive achievement.  All that change comes from individuals banging the drum long enough and loud enough to gather others up with them, and start to influence change at a local, national and international level.  People power is an amazing thing when we choose to use it for good.

One of many celebrity-endorsed anti shark fin campaign posters seen on the streets of Singapore

One of many celebrity-endorsed anti shark fin campaign posters seen on the streets of Singapore

We ourselves feel that what we are doing is just a drop in the ocean. But the ocean would be less because of that missing drop.”

Mother Theresa (1910-1997)