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Underwater Naturaliast Course

Dining etiquette for an Octopus | The Incredibles Showcase

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How do octopus eat their prey

How do octopus eat their prey

Dining etiquette for an octopus: Dig in with all hands!

Nemo’s reef is a fantastic place to spend hours watching these animals just,be. We follow them quietly, as they go about doing their daily things around the shallows of Nemo’s. That alone is one lifetime of diving right there! People often make the mistake of getting way too close to an octopus. Sure, it is sitting there in its crevice, changing colour in response to divers and that is rather cool! But what would be even cooler and perhaps much less disruptive for the octopus, is if we were to curb the excitement and give the animal enough space to get back to its life. This can in fact be plenty times more extraordinary a sight to behold than a tense octopus hiding in a hole! Here we see a young octopus that frequents the ‘first barrel sponge rocks’ area at Nemo’s reef. All of us have met this octopus over the past few weeks and she/he is now very comfortable around divers. When we first saw it, a diver was ten inches away from it with a camera, as it hid inside a crevice, perhaps thinking to itself – Hurry up mister, I’m starving and you’re in my way. As soon as said mister left the scene, the octopus was on the move! We suppose one can identity an octopus with a ravenous appetite by how thoroughly it inspects each rock, tickling every crevice simultaneously with every arm. Note how it expands each arm, turning its entire body in to a large web-like umbrella to trap any molluscs, crustaceans or tiny fish that get flushed out during its invasion.Once prey is in hand, an octopus might crush it, pry it open, or drill a hole in it, drain in some toxins or simply slurp it up, depending on the nature of its catch. Owing to its highly efficient, powerful and thorough hunting technique, an octopus on the hunt is almost always surrounded by a mob of other fish-a mix of allies and competitors possibly. Here we see a few juvenile groupers, wrasses, goatfishes and a tiny cloud of exasperated damsels. Isn’t this simply fascinating?

Video credit: Chetana Purushotham

The Angler Flounder (Asterorombus Intermedius)

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The Art & Science Of Floundering About

 

We all know what a flounder is, and we’ve surely heard of anglerfish, but what in the world is an angler flounder? As though the flounder and angler were each not sci-fi enough, evolution has fashioned this beautiful animal, a.k.a Asterorombus intermedius!

With intricate and elaborate head-to-toe camouflage and a stiff lure protruding from the tip of its mouth, the angler flounder takes the most effective adaptations of two very good predators and blends into something like a super-predator of the sandy bottom. But, why go through all that effort? Is procuring a meal really that difficult in the wild?

For many of us humans these days, finding food would probably mean, cooking a meal after heading over to the market, going to a restaurant, opening the fridge for a quick bite, making a phone call and ordering in (in increasing order of tech sophistication but in decreasing order of per capita effort?). You and I don’t really have to forage, chase or hunt for our food, sustenance and survival. But animals in the wild do, every single time, requiring sophistication and effort! As prey get smarter and harder to catch, predators have no choice but to evolve better strategies to make sure they have that meal on their plate. It is never an overkill.

The angler flounder on the hunt has heightened senses- it swivels each eye, keeping a look out for potential prey- a watchman goby or partner shrimp maybe? Hidden from view by its granular pattern and colour, carefully it crawls over the sandy bottom with webbed fins, waving its bait, casually but concertedly-come fishy-fishy-fishy…

Camouflage for a flounder is extremely effective but also a lot of work. There is the technical aspect of the chromatophores and pigments that need to be constantly redistributed amongst the flounder’s tissues, just the right amount and at just the right time, to give it the right colour, texture and hue. This requires the thinking aspect, where should I position myself? What should I blend in as? Am I on rock or sand or both? Of course, this is where the cleverness aspect comes in- there comes the goby, it is going to turn in my direction in…3…2…1… BAMMM! Meal.

While we might appreciate the beauty of these animals and their wild schemes, it helps to also appreciate all that goes in the making. Take something like camouflage, for instance. The next time you are trying to get too close to a flounder or scorpionfish or any camouflaged animal for that matter, for the thrill of a better view, a photograph or to instigate movement, remember that disturbing it will not only blow its cover, but also cost it a day’s meal!

Video Credit: Umeed Mistry
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#Ocean Love: Book of the Month – What a Fish Knows, Jonathan Balcombe

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What a Fish Knows: The Inner Lives of Our Underwater Cousins

Jonathan Balcombe, 2017

To me, diving at the same dive site over and over is never boring. It feels like going to hang out at a friend’s house. There is pleasure in seeing them again and there is comfort in knowing all your favourite things about their place are still there.

I have a close friend at Dixon’s Pinnacle, here in Havelock; a cute and curious circular batfish (Platax orbicularis).  When I dive Dixon’s, typically the first thing I see is a 10 meter tall wall of batfish gingerly fighting the current. And nearly every time, there will be that one batfish that peals away from the school and swims over to where I am. Swimming barely a meter away, this batfish accompanies us to the second pinnacle, and waits patiently while we look at the big-eyes hovering behind the third pinnacle. She (or he) even ascends with us to the top of the first pinnacle towards the end of the dive while we look for juvenile emperor angelfish.

The probability of this happening is so high that I can confidently brief my divers about the batfish and sure enough, there my buddy will be!  I have grown attached to this batfish and find it especially comforting when she (or he) accompanies me until the mooring line at the end of the dive, even though it is a good 30 meter swim into the blue that my batfish buddy must swim back to the pinnacles, alone.

Book Review: What a Fish Knows, Jonathan Balcombe

My buddy and I say our goodbyes at the end of a dive at Dixon’s Pinnacle.Picture credit: Mayank Singh

I have not been diving for very long, but it did not take me much time to realise that while it is very difficult to tell individual fishes of a species apart , there is no doubt that every individual is different. Fishes, much like us, have different personalities and temperaments, which may be a sum of their life’s experiences. Although there is a lot that we now know about the lives of fish, there is so much more we are yet to understand about them.

The batfish at Dixon’s and several other underwater friends (and enemies) I have made around Havelock have got my mind constantly churning up questions about what they are doing, what they perceive, feel and think! And as though the forces knew exactly what was going on in my mind, the universe dropped a fabulous book into my lap (alright, read: kindle).

‘What a Fish Knows: The Inner Lives of Our Underwater Cousins’ is an eye-opening and mind-boggling account of fish lives that ethologist Jonathan Balcombe uses to make a strong case for fishes as being sentient beings and not merely animals to be caught or consumed. Balcombe bases his argument on decades of science and numerous anecdotal stories, told in a way that really draws you in. While you may or may not agree with some of his interpretations, the facts and observations he states are real.

Fish swimming in schools are not an arbitrary group of fish moving in arbitrary directions. They have leaders, informants, and navigation-communication systems. They have culture.

Photo credit: Vandit Kalia @vanditkalia

This book comes at a time when fish populations are steadily crashing across the globe. It is taking destructive and wasteful fishing practices to meet the ever increasing demand from the seafood market, the live pet trade, traditional medicine, aphrodisiacs, you name it! There is a need, now more than ever, to talk about fish, as individuals whose lives have intrinsic value and not just commodities that measure in kilograms, pounds or tonnes.

To begin with, we hear very often that we ‘evolved from fish’.  There is significant scientific evidence to show that we are descendants of fish and fossils of the first fishes dates back to 530 million years ago. Today they make up 60% of all vertebrate animals on earth. They have had plenty of time to adapt, evolve and diversify extraordinarily; just, not within our view.

We may never truly know what it is that fish perceive, but we are able to figure out the mind blowing extent to which their sensory abilities have evolved – vision, speech, hearing, taste and touch. Balcombe spends time on each of these and several ‘sixth senses’ including navigation using lateral lines, ultraviolet code language and hunting with electroreception!

Fish can think, calculate and memorise. The ‘three second goldfish memory’ is now a thing of the past. Wouldn’t you agree that a three second memory would be frighteningly painful for a manta ray that plans to travel between specific seamounts in search of plankton blooms and then go back each year for a routine clean at the exact same cleaning station, on exactly the same corner, of the exact same coral reef?

What a Fish Knows, Jonathan Balcombe - Review

Fishes such as this Dascyllus uses its lateral line system (seen as the thin line arching across its body) to detect movements and navigate its surroundings

Picture Credit: Gunnhild Sørås  @gunnigullet 

The most interesting part of this book (and you can tell while reading it), is also probably what Balcombe holds closest to his heart. Going beyond the senses, beyond just cognition, he asks- do fish have feelings? Do they have beliefs?

Through studies and stories that are amusing, sad, and hilarious and awe inspiring all at once, we see how fish can have feelings that range from stress to joy. They can appreciate the warmth of the sun in the same way we do after a cold rainy day. A visit to a cleaning station relieves their stress the same way a good massage does ours. They can be inquisitive, deceptive, empathic and playful. Fish have culture, traits that are not innate and need to be learned through the course of their lives.

It makes you wonder why it has taken us so long to acknowledge that fish are not just instinctive but are also intelligent too. Is it because we just have not spent enough time with them? Is it because their faces are not as expressive as other animals that we relate to, like primates? Speaking of primates and how intelligence is contextual, a quote by Albert Einstein comes to mind. “Everybody is a Genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

“You don’t need to have fur and feather to have a personality. Scales and fins will suffice.” – Jonathan Balcombe

Picture credit: Vikas Nairi  @vikasnairi

In conclusion, this is a really fun book but also pertinent given the current state of affairs where fishes in our oceans and rivers are concerned. We have learned fish behaviour enough to know how and when to detect and catch them using sophisticated technology and yet we fail to use this same knowledge to stop decimating their populations and ecosystems.

Try spending about five minutes on your next dive observing a cleaning station. The interaction between cleaners and clients on a reef alone tells so much about their social systems and will show you that “fish aren’t just alive, they have lives”!

In the meantime, after having read this book, I look forward to heading back to Dixon’s to meet my buddy the batfish again. Do you think that they know that we know what they know?

What a Fish Knows is easily available online, in paperback and kindle versions!

Read other posts in the #OceanLove Book of the Month series here

The author, Chetana is a PADI divemaster and resident biologist at DIVEIndia in the Andaman Islands. She is an alumnus of the Masters program at the Wildlife Conservation Society -India program and National Center of Biological Sciences in Bengaluru. She has been diving and exploring the Andaman Islands since 2013. She is also deeply excited about forests, birds, reptiles and amphibians.

Who Are You Calling an Invertebrate?

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Ernst Haeckel (1834-1919) juggled many professional hats during his life – he was a professor, biologist, philosopher, physician, and in the middle all that, he found the time to be a phenomenal artist as well. He is known for his enormous contribution to science, through the several new species he discovered, scientific concepts he theorized and biological terms he coined. He is also admired across various disciplines for his exquisite and influential collection of illustrations known as the ‘Kunstformen der Natur’ or ‘Artforms in Nature’ (sketched and painted between 1899 -1904).

If you are looking at any of these plates and admiring them for their abstract beauty or commending Ernst Haeckel for his marvellous attempt at science-fiction, take a look again. These are all real marine animals. They actually exist in these very shapes, patterns and forms. Ernst Haeckel observed and appreciated that in these underwater beauties; several decades before the advent of recreational SCUBA diving.

What do all these animals have in common? On careful observation you will notice that, yes they are all stunningly beautiful, there is inherent symmetry, but also, they are all types of ‘invertebrates’. They are all animals that lack a vertebral column or a backbone/spine inside their bodies.

Speaking of invertebrates, I never did understand the figurative use of this term in our society. To call someone a ‘spineless’, ‘invertebrate’ is to describe them as weak, cowardly, inadequate or ineffective. How did this association come to be?

Over 97% of animals on this planet are spineless, especially in the ocean. Some of the most venomous (box jellyfish), strongest (mantis shrimp), smartest (octopus), fastest reflexes (mantis shrimp again!), largest (giant squid), cutest (alright, this one is heavily subjectiveJ) are some form of marine invertebrate or the other.

A barrel sponge (Xestospongia testudinaria) can dwarf you despite your tank and fins
Vandit Kalia @vanditkalia

When reading about evolution and biology today we learn that, more and more, science doesn’t consider evolution to be progressive. Meaning to say that through the course of geological time, being older or having appeared first is no longer considered ‘primitive’ and being more newly evolved doesn’t make you necessarily ‘advanced’. Scientists now prefer to use terms such as ‘ancestral’ and ‘recent’ instead, with much less value judgement. Take sponges for example. Sponges consist of hollow cavities held together by protein fibres and they have numerous different types of cells, to filter food from water that is brought in and sent out. Sponges constitute some of the oldest animals to have ever lived (fossils as old as 640 million years old), and they still exist, all of 9,000 species of them.

A wise old coral colony
Gunnhild Sørås  
@gunnigullet    Vikas Nairi  @vikasnairi

Backbone-free animals are everywhere, and some of them literally shape our world. During the journey of a single dive in a shallow reef, we are immersing ourselves into a world whose multi-dimensional foundation, was built over millions of years, by the remarkably and astonishingly, spineless coral. Stony coral get a majority of their energy from their in-house photosynthetic symbionts and use it to put down calcium carbonate skeletons, layer by layer, that are strong enough to last years, centuries, and millennia. Corals live and lay the foundation of coral reefs, and then everyone else, from feather-duster worms to fish, start to step in to look for ways to build their own lives. An ecosystem is formed.

A closing sea anemone
Chetana Babburjung
 @chutney_babburjung

Through the course of your dive, you will surely find yourself smiling at clownfish in their anemones. Unlike a majority of their coral cousins which live as colonies of polyps, sea anemones are typically singular polyps lined by a whorl of stinging tentacles. Hidden in the centre of the anemone, if clownfish will allow you to see it, is an opening that is its singular window to the outside world- mouth and anus. It happens rarely and very difficult to catch with the naked eye, but sea anemones can move.

A peacock tail anemone shrimp busy on its host anemone
Gunnhild Sørås 
@gunnigullet

Anemones are cheerful hosts that collaborate not just with clownfish, but a variety of crustaceans, especially anemone shrimps and crabs that promise to help the anemone stay clean in return for a home.

Nudibranchs, a cryptic treasure.
Gunnhild Sørås 
@gunnigullet

Some of the more cryptic treasures to look out for on a reef are sea slugs, who are now coming out of the shadow of their celebrity cousins-the octopus. Among the mind-blowing diversity of sea slugs, nudibranchs are unique in that they breathe through gills placed outside their body (hence the name). While they have a versatile diet, some of them love eating fern-like hydroids. Hydroids just like their relatives -coral, anemones and jellies- are laced with stingers. No matter, Aeolid nudibranchs eat them anyway, carefully pocketing the stingers for later use as self-defence. Similarly sap-sucking slugs feed on algae but extract the algal pigments and keep them alive in their bodies for their own personal photosynthetic use. Is that ingenious, or is that ingenious?

Ernst Haeckel was particularly taken by the symmetry he saw in nature. A classic example for us would be- Echinoderms. A group found exclusively in the ocean, echinoderms are the sea stars, feather stars, brittle stars, urchins, cucumbers and several other unbelievable but underappreciated marine invertebrates (and therefore warrant a separate feature altogether).

A mollusc larva dancing in the blue
Vikas Nairi 
@vikasnairi

A typical shallow dive might last forty-five minutes to an hour and we may still not be ready to ascend to the surface, even though the gases in our tanks and bodies might dictate otherwise. But wait, the dive isn’t over yet.  Safety stops are the best time to connect with bizarre but brilliant drifting creatures, as we hover in an endless soup of plankton.

At the end of the day, if Boris Johnson were to ever call me a “supine invertebrate jelly”, I think I might just say, thank you.

Watch this space for our next  showcase on the underwater lives of the Incredibles.

The author, Chetana is a PADI divemaster and resident biologist at DIVEIndia in the Andaman Islands. She is an alumnus of the Masters program at the Wildlife Conservation Society -India program and National Centre for Biological Sciences in Bengaluru. She has been diving and exploring the Andaman Islands since 2013. She is also deeply excited about forests, birds, reptiles and amphibians.

Back to School dive package

Back To School Dive Package: Underwater Naturalist

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Introducing the Back to School dive package!

If the ocean were your classroom, would you like to go back to school?

If you have been looking to know more about the marine environment and how life works underwater or if you would like to learn how to identify fish and other reef organisms, this two day package is for you! Learn more about some of the conservation challenges our oceans are facing and help us come up with solutions to protect these magical places.

We also offer this package as an Underwater Naturalist specialty through PADI and SSI open to any diver with at least an Open Water certification.

This program runs over two days and includes short theory classes and discussions along with four open water dives. You can also choose to do a night dive as one of the four dives.

During this course we introduce you to some of the numerous ocean ecosystems (yes, there is more than one!). We take you through how environmental factors shape these coral reefs as well as our experiences when we dive these sites. Reefs are extremely diverse spaces, where survival is based on cut-throat competition but also to an equal measure on cooperation and forging partnerships. Learn about some of these interactions as they unfold like a show around you on every dive! You also get to try your hand at identifying fish and other reef organisms and be a part of REEF LOG, the first diver-led reef monitoring program here in the Andamans!

Image courtesy: Gunnhild

Marilia and Jugal were the first two students on this course package.  Here is what Marilia had to say, Diving became much more interesting after a short Underwater Naturalist course, that basically introduced micro life, which I couldn’t identify before, and explained the relationships between the animals down there.” Jugal feels that understanding more about the underwater environment is rewarding on various levels. Knowledge of fish identification, understanding of interactions between organisms, relation between organisms and their environment are few aspects this course develops, which make every dive more interesting, fun and fulfilling. It also makes you aware of the importance of conservation through individual and collective efforts. Learning through discussions and reading along with practical demonstration (during dives) of everything in live action makes for a beautiful experience while developing a special tool to take away and make use of in all future dives!”

Diving with a naturalist’s perspective can also be fun.

To get more information on the same, please email us.