Diving

The Rapture of the Deep

DCIM100GOPRODeep diving is something that I am passionate about – especially if it involves a shipwreck. It is a chance for me to push my skills, training and equipment and to explore some of the lesser dived or known sites. However this comes at a considerably higher risk which involves specialised training and equipment to manage safely. One of these risks is Nitrogen Narcosis – aka “the rapture of the deep”. Not a lot is known about the causes of nitrogen narcosis, but it is a narcotic effect brought on by the increased partial pressure of nitrogen in the breathing gas at depth. The threshold for nitrogen narcosis is different for each diver and can even vary dive-to-dive within a diver, depending on many factors. I usually enjoy getting a little “narc’d”. It can be quite euphoric and enjoyable if managed well. Nitrogen narcosis itself is not dangerous, unlike decompression illness, and there are no long lasting effects – no nasty hangovers. What can be dangerous though is the impaired actions of the diver experiencing euphoria. It’s essentially diving drunk. Nitrogen narcosis, like other narcotics can also present as paranoia and confusion which can lead to panic. Bad news in any depth of water. Thinking about these effects, I thought I’d share a story I wrote about a dive many years ago where I was overcome by narcosis paranoia in the hope that others can learn from my bad experience. This dive was a huge learning experience for me and still serves as a source of healthy anxiety before a deep dive. Nitrogen narcosis is not something that can be (nor should be) avoided, but it is certainly something to be aware of.

Before I get into the story, I should also make a quick note about solo diving. This practice is often frowned upon in diving circles and I do agree that diving with a buddy significantly reduces many risks associated with diving. However, I also believe that with proper training and additional equipment, many of these risks can be minimised and solo diving can be conducted reasonably safely. The training that I have done to enable me to dive outside the recreational limits had a special focus on redundant equipment and self reliance in emergency situations. I personally find solo diving to be quite relaxing and enjoyable, but only because I take the necessary precautions when I do it (which isn’t often).

When 3 things go wrong…

“If you turn right when you get to the anchor you’ll see the boiler. Then if you go left from there, you’ll get to the stern section” said my buddy.

“No worries. Too easy”. I think to my self.

There are some days when you really should just stay in bed. I was gearing up to dive a wreck off Sydney. It was one of those magic days on the water, with the sun newly risen and barely a whisper of a breeze to ruffle the smooth surface of the ocean. Unfortunately this magic had been marred by the realisation on the trip out that I’d left the undergarment for my dry suit laying on the back seat of my car. Idiot! This was to be the least of my troubles on this dive. As I was gearing up, to my horror I discovered that my fins were no where to be seen. They too were laying in the boot of the car along with my ankle weights. The ankle weights didn’t really concern me, but without my fins I was resigned to being the boat boy. Shit! how could I forget my fins! The undergarment and ankle weights were no big deal, I could get by without them, but my fins! You Idiot! I cursed my self again.

My buddy has said on many occasions “when you have 3 things go wrong on a dive, any 3 things at all, call it off”. Hmmmm, fins, ankle wights, undergarment…. I should have taken that advice.

The two others on board rolled over the side and descended onto the wreck 50 m below. I watched them disappear into the inky blue depths. 20 minutes later my buddy reappeared on the surface. He was diving in a wetsuit and was getting cold so had called his dive short. He climbed back on board raving about the excellent visibility and the fish life. He suggested I take his fins and go check out the wreck. It didn’t take much to talk me into it, although I could hear his words (spoken to me so many times) going through my head “when 3 things go wrong….”. But I couldn’t resist. I had gotten up early and made the trip out here and I was grateful to him for the offer of his fins, giving me the opportunity to explore this wreck that I’d heard so much about.

So I turned on the air for my two back mounted tanks, checked my gauges and climbed into my harness. As I was attaching my stage tank (a 3rd tank containing a Nitrox mix to reduce the ascent time) my buddy described the layout of the wreck to me.

“If you turn right when you get to the anchor you’ll see the boiler. Then if you go left from there, you’ll get to the stern section”.

I was so excited by this stage as this was my first time on this wreck and the conditions couldn’t have been better.

“What bottom time are you going to do?” He asked me.

“I’ll just do 10 minutes” I replied, feeling safe in the knowledge that I’d previously planned a 20 minute bottom time with breathing gas to spare.

I donned my buddies fins, went through my final checks, rolled over the side and kicked below the surface to the anchor line.

Breathe in breathe out…. slow, even breaths. Equalize. The particles suspended in the water whiz past me as I descend. I’m dropping fast. Breathe in, breathe out, equalize. Check instruments: depth – 12 m, dive time – 0:00, air – 223 bar. Every thing looks good. I feel great! I love this part. There is nothing around me. The only reference is the anchor line in front of me, disappearing into oblivion. I feel like I’m in free fall.

The visibility at this depth is only 5 m at best. My descent continues. 15 m… 22 m… 25 m… The visibility opens up. I can just make out the wreck below me sitting in 50 m of water. The gunk in the water above me partially blocks out the sunlight. I turn on my torch, more for comfort than anything else. I’m breathing a little harder now with the increased pressure so I adjust the resistance on my reg and add some more air to my dry suit to slow my descent. as I pass through 30 m depth I’m still dropping fast so I add some air to my BC to slow my descent.

Instrument check: depth – 48m, dive time – 0:02, air – 204 bar. As I arrive at the bottom, I try to unclip my reel from my harness. My fingers are clumsy, I must be narc’d but I still feel fine. I get my reel free and manage to tie onto the anchor line. I take a couple of seconds to catch my breath and gather my senses. Breathe in… breathe out… Wow! I am narc’d! I can’t concentrate…. better check my gauges: 0:05 dive time. What happened to those 3 minutes! This is fantastic! The vis is at least 30 m! 3 huge trevally cruise past me glinting bronze in my torch light. I watch them disappear into the distance. I’m surrounded by wreckage covered with tiny pink, purple and white bryozoans. Orange and yellow sponges fight for space with iridescent algaes. A school of pomfret, glowing golden in my torch light, cascade over parts of the wreck. I’m loving it!

Ok, what was I doing?…. Turn right from the anchor…. Right or left? No it was definitely right…. Which way is that? Ok concentrate now… this is my right hand… turn that way. I see the edge of the debris field and sand…. Where is the boiler? I keep turning. There’s the anchor…. Ok, I’ve turned right around. maybe it was left…. Ok turn left…. Wreckage… Sand… Anchor. I’ve turned around again…. where is that boiler? it was definately “turn right from the anchor”…. Ok, calm down, breathe. Should I bail out? I’m really really narc’d and I feel like I’m really pushing my abilities. No I’m ok, I’m well trained, I’m using familiar equipment (apart from the fins), my skills are up to scratch and I have heaps of air… I can handle this situation. Stop, breathe, think and act. Breathe in….breathe out. Think: “turn right from the anchor…” Act. Ok…. turn right. Ok I see a shadow out on the sand…. Is that the boiler? All the way out there? Ok… Start swimming…. It’s hard work…. Bugger that. I’m not swimming out there. Turn around… Which way?… Oh yeah, that’s right, it won’t matter.

I turn around and reel my way back to the anchor. I’m so narc’d. I can’t think. Calm down…. Breathe…. Check instruments: dive time 0:08 minutes. damn! I’ve wasted most of my bottom time. Air – 182 bar. I can’t think straight.

I close my eyes to try to gather my thoughts. Breathe in… Breathe out… Ok…. I’m on the edge of the debris field. I’ll just follow the sand line for a little bit. Which way? There’s a slight current… I’ll just drift along with that…. No wait!… I tell my students not to do that in the open water course… But I only have 2 minutes left. I’ll just drift a little way, then turn around. It’ll be fine.

I move along the wreck with the current. There are some beautiful little gorgonian fans, and some little pink bryozoans. Three juvenile blue wrass scull along beside me…. This isn’t so bad… A little leather jacket moves out of my way. Wow! this is a beautiful wreck! There are scattered deck plates and beams all around me. I wish I could have found that boiler or the stern section. Ah well next time… Oh shit! what’s my bottom time? 0:10! Shit! Turn around. I swim into the current. It’s not strong, but I have to work harder. I can feel my breathing rate increase with the extra effort. I reel in my line as I swim back to the anchor.

Back at the anchor. Instrument check: dive time – 0:11 minutes, air – 156 bar. My computer tells me that I require a 4 minute stop at 6 m with a total ascent time of 13 minutes. It’s ok, I have plenty of air and a 40% nitrox mix in my stage tank. Ok… relax… I try to detatch my line from the anchor chain, but my fingers just won’t work the way I tell them to. Finally the line comes free (I was so close to cutting it). I secure the reel to my harness and begin my ascent. Dive time – 0:14. Shit! I stayed way too long. I’m ok, I’ve got plenty of air left. I make my way up the anchor line. not too fast….dump air….breathe in breathe out. Up I go… at 25 m (the safe operating depth for a 40% nitrox mix) I reach for the reg on my stage tank but unbeknownst to me, the hose is caught on the buckle. I pull at the reg, but it wont come free. I’m still going up… dump air…. breathe…. I’m thinking more clearly now. Ok stop… Breathe… Think: “why won’t the reg come free?…. It’s caught on something”… Act: follow the hose with my hand. Ok, it’s caught under the buckle here. Ok, there it goes. I pull the reg free and start to breathe my nitrox mix. Instrument check: Dive time – 0:18 minutes, gas – 200 bar, 10 minute stop now required at 6 m. I make the gas switch on my computer. it re-calculates my ascent profile taking into account the new gas mixture I’m now breathing. Dive computers are such wonderful things! 1 minute of decompression now required at 6 m, total ascent time, 7 minutes. I slowly make my way to my 6 m stop and wait for 1 minute. Up to 3 m for just 5 minutes (oh how I love nitrox).

Hanging on the anchor line at 3 m I have time to contemplate the dive. I was out of my depth (excuse the pun). It all started out wrong. I feel lucky to be back near the surface. Things could have really gone wrong down there. Well, actually, maybe I’m not lucky, per se. When I knew I was getting into trouble, my training kicked in: Stop, breathe, think and act. And I was able to gather my self sufficiently to be able to get back safely. Nevertheless, I’ve learnt some valuable lessons from this dive. I should have bailed out when I felt the narcosis become overwhelming. Always start the dive swimming into the current. Practice practice practice with your equipment so that muscle memory can relieve some of the task loading on your brain at depth. And especially “When 3 things go wrong…”

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Shark!

Did that get your attention?

There has been a lot of media attention surrounding sharks recently, starting with that terrifying footage of Mick Fanning and a number of incidents on the NSW north coast. Following on from these incidents there have been calls from a very vocal minority of ocean users to ramp up efforts in shark control measures. It should come as no surprise that I don’t support lethal methods of shark control. As far as I’m concerned there are much bigger risks in life than the threat of being bitten by a shark. If we wish to enjoy the ocean we should know the risks and accept that we share this wonderful environment with these apex predators. However, with all of the media hype, it’s easy to forget that we also share the ocean with some other amazing animals, which is what I though I’d share today.

The beauty of the ocean never ceases to amaze me.

A picture tells a thousand words Jan – Feb Lizard Island trip

I was joined by my sister, Kaz (author of the Madagascan Adventure series) on my latest field trip to Lizard Island. We repeated the surveys that Kylie, Grant and I had conducted last time and ran an experiment to investigate whether a subordinate fish would decide to move out when exposed to an adjacent coral of varying size and with different numbers of fish already residing in it.  I hope you enjoy this visual expose of our time there.

Life at Lizard

The Experiment

For a brief description of the experiment we ran see here.

Day Reef trip

We were honoured to be invited by Anne, Lyle and Alex for a trip out to Day Reef on our day off. It was meant to be a dry day for us, but we were willing to make the sacrifice!

A small win for the PhD!

I had a small win this afternoon!

I’m back on Lizard Island at the moment and over the last few days I’ve been setting up an experiment.

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This experiment is to try to determine what factors might influence a subordinate individual’s decision to either stay within a group or to move out. I am testing habitat size and habitat saturation. To test these factors I have created groups of three fish (two adults and a subordinate) in medium sized corals. These groups of three are then presented with either a small, medium or large coral containing either 0, 1, 2 or 3 other fish.

Wow! that’s confusing when I write it all out. Here’s a diagram of my experimental design.

Experimental design

Over the last 48 hours Kaz and I have had the first trial running. In trial 1 the group of three fish were presented with an empty coral which was smaller in size. Last night the subordinate actually moved into this smaller coral. I can’t really draw any conclusions from this one trial, but if we keep seeing this happen, it could indicate that the degree of habitat saturation is more critical than the size of the habitat in determining whether a subordinate will stay or leave a group. In terms of group formation, it could indicate that groups are more likely to form when the habitat is highly saturated (i.e. when there are not many vacant corals). That’s exciting for me and my thesis 🙂

More info on my research

My research

Initial project report

Lizard Log series starting here

Lizard pics

Fish tattooing

Fish tattooing

Capturing the fishies

Capturing the fishies

Goby hunting.

Goby hunting.

Kaz shopping for corals

Kaz shopping for corals

Kaz measuring

Kaz measuring

It's not paradise every day...

It’s not paradise every day…

A MADAGASCAN ADVENTURE: Part 3

Part 3: Conservation and the Vezo

I promised to talk more about the Vezo people, whom I lived amongst for three months, in my last post, so here we go…

The Vezo are known to be the best fishermen in Madagascar. The name ‘Vezo’ translates to, ‘ROW!’ (Literally the imperative form of the infinitive verb ‘mive’, so it’s the command ‘ROW!’), which is apt, as they may well be the best seafarers in Madagascar as well!

Readying the pirogue

Readying the pirogue

Local fisherman. Photo by Sandy Maksimowska.

Local fisherman. Photo by Sandy Maksimowska.

(See more of Sandy’s beautiful photos here)

Living a hand to mouth existence as they do in Andavadoake, is a hard life. It begins before sunrise and ends when you have enough fish to feed your family, and on a good day you might have a little left over to sell as well.

The ocean and the seafood it provides is vital to the Vezo as the main source of protein in their diet and a crucial source of income. The sandy soil that surrounds their homelands make agriculture near impossible, so the sea really is their food bowl and therefore, needs to be managed in a sustainable way. Not to mention the inherent cultural value that the ocean represents for the Vezo.

Who are we, coming from rich, developed countries, to tell these subsistence fishermen what they can and can’t fish and what sizes they should be? The people of Andava (and beyond) don’t have the luxury of being choosy when it comes to their catch. They don’t have the luxury to be able to afford to throw things back if they don’t meet our conservation standards.

However, with a booming population (the village of Andava doubles in size every 10-15 yrs) comes increasing pressure on the once abundant food bowl; the sea. And what about the national and international (Europe and Asia) fleets that fish these waters as well? This has amounted to huge pressures on the inshore reefs and eco-systems that feed so many.

Blue Ventures (BV) recognized the challenge facing the reef and its people and seeks to engage and educate the community not only on the issues of overfishing and destructive fishing practices, but also to assist in developing strategies that will help fishers fish more sustainably (BV’s efforts are not solely focused on the marine environment. Take a look at their website to learn more about their integrated approach to conservation, incorporating community health and education programs! I simply cannot cover it all here). This has seen the adoption of temporary and permanent Locally Managed Marine Areas (LMMA’s) and the development of aquaculture projects such as sea cumber and seaweed farming. Aquaculture is growing rapidly, generating alternate incomes for families and also getting women more involved in income generation and importantly, management of these industries.

Seaweed farming in Tampolove

Seaweed farming in Tampolove

Seacucumber pens in Tampolove

Seacucumber pens in Tampolove

BV’s establishment in the area came via an unlikely hero… Octopus! They’ve had incredible success with this lucrative fishery, which I believe, cemented the relationship between BV and the wider community. After the first temporary closure of the octopus fishery on one small section of reef in 2004, the community saw amazing results with unprecedented catches, and an increase in number and size of individuals. This strategy has been reproduced up and down the coast over the following years, and has now gone countrywide with communities in the northwest and northeast of the country using the same model, and Madagascar’s government establishing an annual national closure!

On the back of this success, many of the fishing communities saw the benefits of marine reserves and created their own network of reserves called the Velondriake (means ‘to live with the sea’ in local Vezo language) which comprise 640 sq km of protected area. It encompasses 25 villages and representatives from these villages establish and protect their marine reserves under the LMMA structure. BV volunteers collect data on both reserve and non reserve locations to help with the decision making and build a stronger case for the implementation of marine reserves.

Sustainability is key to the Vezo’s survival – what more of an incentive does one need to protect the Great Reef? And coupled with the adoption of aquaculture projects and other alternative income activities, such as eco-tourism, are showing this community that there is hope for their future.

President of the Velondriake stating the rules on opening day

President of the Velondriake stating the rules on opening day

Octopus reserve opening day on Nosy Fasy

Octopus reserve opening day on Nosy Fasy

My experience in Andavadoake told me that yes, conservation is a luxury, and yet it is necessary for the survival of fishing communities, not only in Madagascar. It was amazing to see so many people in this community willing to make sacrifices in order to mitigate the challenges they face with food and income security. It’s inspiring to see a community so focused on a common goal, which will not only benefit them as a people in the long term, but the environment upon which they rely, as well. Win, win!

So what did I learn/what have I taken away from the experience?

I’ve learnt to appreciate living a day-to-day existence, rather than always looking to the future for the next big thing – though whether I can maintain this back in the fast paced, developed world, remains to be seen. I’ve learnt to be more mindful of our oceans, what we’re taking from it and what we’re doing to protect it. I was inspired by many of the staff and volunteers I met along the way and am grateful for having made some great connections with people I know will be my friends for many years to come.

People always ask me, “what was your favourite part?” This is such a difficult question, but I guess my answer would be: Having the opportunity to live with the people of Andavadoake. Learning (sort of!) their language, listening to their stories, meeting their families, observing and participating in their way of life. Having that sort of context overlaid on the volunteer work we were doing, was for me, the best part. I wasn’t just counting fish, I was contributing to building a sustainable future for the people I met along the way.

On the whole, it was eye opening, enriching, challenging at times and a whole lot of fun. It gave me an appreciation for what it is to live in a remote community and the challenges they face each day and it gave me perspective on my own life.

Beautiful Andava Rock

Beautiful Andava Rock

And I saw the boababs and lemurs that had lured me here in the first place!

Boababs!

Boababs!

Brown Lemur in Parc National de I'Isalo

Brown Lemur in Parc National de I’Isalo

Ringtail lemurs in Réserve Park

Ringtail lemurs in Réserve Anja

Magical Indri in Parc National Andasibe

Magical Indri in Parc National Andasibe

Simporna (Silky Sifaka) in Parc National de Marojejy

Simporna (Silky Sifaka) in Parc National de Marojejy

Misaotra Bevata!

A Madagascan Adventure: Part 2

Part 2: Life as a volunteer

Picking up from where I left off in the last post, after our sojourn through the Madagascan countryside, our initial culture shock somewhat subsided; my fellow volunteers and I were finally in Andavadoake – our home for the next 6 weeks (for some of us, the next 12 weeks). Following that first hypnotic sunset, it was time to get stuck into life on site. Our living conditions were basic but comfortable, with huts situated right above a small cove called half moon beach. We’d wake to the sound of the waves and passing pirogues (wooden sail boats) heading out for the day’s fishing.

Beach Huts

Home in Andava

Our diet consisted of mainly fish, beans and rice, with a few variations on the theme from time to time, including the delicious Malagasy beef equivalent – zebu; The mighty zebu is also used to draw carts, plough fields and buy wives and is a precious commodity for many tribes in Madagascar. I couldn’t get enough of the fresh seafood, though we did miss the abundance of fresh fruit and veg we’re used to back home.

But basically, we were living in paradise!

Zebu

The mighty zebu

mackerel

Freshly caught lunch

A typical day consisted of 2 dives in the morning, many with whale sightings on our ride out to site, a stroll to the village for a cup (or five!) of peanuts, study/hammock time followed by duties, lectures, presentations or language lessons then dinner and ‘tantara’. Tantara roughly translates to ‘story’ in English, and we all took turns to tell a story, run an activity or game, show some pictures etc. for our evening entertainments

A typical week was diving Monday-Friday, Saturday land based activities like visiting mangroves or learning to cook samosas and boko boko (deepfried dough filled with chocolate – yum!), followed by a night of shaking our butts Vezo style in the local bar, Dada’s… the Malagasy’s put us Westerners to shame! Those guys can seriously move. Sunday was our day off where we got to go exploring! We embarked on baobab walks, whale watching, spear and lobster fishing, island picnics, snorkeling trips and even an overnight camping trip on a nearby island. One of the highlights of the trip!

making samosas

Making Samosas. Photo by JD Toppin

(for more adventures, check out JD’s travel blog here)

camping

Camping at Nosy Ve

We were assigned English partners and spent three sessions a week imparting our knowledge of the English language onto them with varying degrees of success. During the expedition my English lessons consisted of the pleasure and delight of trying to decipher then reinterpret the PADI divemaster manual for one of our boat drivers and dive master in training, Patty. Challenging? Yes. Poor Patty. I think I successfully confused him rather than enlightening him! If you’ve ever read a PADI manual, you may understand my struggle.

But back to my reason for travelling to Madagascar – the marine environment. I was here to count fish! As a volunteer, I had to learn 150 fish species along with 36 benthic and invertebrate species. Thank goodness our coral ID was limited to 11 hard coral formations and simply, soft coral. We didn’t have to be species specific. Those scientific names may have killed me! As it was, when I closed my eyes at night, I would see fish and corals flying at me and I’d be chanting names over and over in my head!

Luckily for me, I’ve been plaguing my brother with fish questions over the years of diving together, so I had a basic knowledge of some fish families before we even started, which was an advantage. But when it came down to species level, I still needed work, especially as not all the names were the same – moon wrasse became crescent wrasse, leather jackets became filefish, bullseyes – sweepers, flutemouth – trumpetfish…

Benthic on the other hand, was a bit of a struggle. I’ve never been overly enamored with benthic life, accepting kelp and sea grass, sponges, and corals as an important part of the ecosystem, but indifferent to their actual role and avoiding invertebrates such as sea cucumbers like the plague (ick!). However, our passionate field scientists were somehow able to convince me that benthic was cool and I subsequently looked forward to a bit of benthic surveying.

Goniopora

My fav coral species, Goniopora; despite it’s appearance, this is a hard coral! Image from Wikimedia Commons

I even overcame my fear of sea cucumbers one spring tide, when we helped the aquaculture farmers with their data collection. I opted to be the weigh-er, thinking it would be the best job to avoid handling any squishy, slimy, boneless creatures. Turned out, I had to pick up every. Single. One. Not once, but twice! After a few girly squeals, I managed to get into the swing of things. I can’t say I love them as a result, but I don’t have that fleeting moment of panic when I see them now.

seacucumbers

Zanga! (Seacucumbers)

The sites we dived ranged from healthy to pretty destroyed. The ones that didn’t look so great were affected by a combination of cyclone and storm damage plus destructive fishing practices and overfishing. Education and subsequent dinas (local laws) are in place, to outlaw destructive fishing methods such as poison fishing and beach seining. This has improved the health of the reefs in many areas, which is encouraging to see. Most sites were populated with small to medium reef fishes such as schools of snapper, fusilier, parrotfish and many species of wrasse. But the best part was diving in the protected areas and seeing HUGE fish, such as blue spined unicorns, often in schools, which seemed to be a sign that the protection zones were working! Win!

snapper

School of snapper. Photo by Niki Boyer

Diving with species knowledge really made it such a rewarding experience. It was always exciting identifying something you hadn’t seen in the water before, or something you struggled with! And I had some really special encounters including seeing a turtle – turtles are rare as they’re hunted as a coming of age ritual – hearing humpback whales sing quite regularly, a myriad of new nudis (colourful seaslugs), schooling, yes schooling Moorish idols, and even a sailfish!!

nudibranch

Some kind of Halgerda Nudibranch. Photo by Niki Boyer

Expedition life was an incredible existence for me. So far removed from my everyday reality in Australia. It was refreshing to be learning again and to be immersed in a culture and way of life I never knew existed. I will talk more about the people of Andava in my next post…

THINGS I MISS…

Being in or on the water every single day!

The infinite stars at night

Watching pirogues sail by

Constant sound of the ocean

The pace of life

The vazah and vezo friends I made

My hammock

Kids yelling ‘Salama’ everywhere you go

The dancing!

 

THINGS I DON’T MISS…

Sand in my bed

 

hammock day

View from my hammock

hammock sunset

Sunset from my hammock

stars

Stars! Photo by Ben Large

Initial Project Report

Slide1

Last week I presented at the University of Wollongong Post-Graduate Conference. I have adapted my presentation below as it was a good overview of my project to date. By way of some background, each year the biology post-graduate students are set a challenge to incorporate an object or personality into their presentations. This year it was Leonardo Dicaprio, so keep an eye out for some celebrity cameos.

So without further ado, let’s start this talk by having a quick think about why animals form groups. We might imagine that in a perfect world, the ideal way to ensure that you maximise your genetic contribution would be to breed as soon as possible and as many times as possible. This would involve leaving the natal territory as soon as possible to pursue individual breeding opportunities.

Slide2

So why then do we see so many examples in nature of reproductively mature animals which routinely delay or (in extreme cases) completely forgo their own reproductive opportunities in order to join and remain within a group as a subordinate non-breeding member?

The answer is that we don’t really know. We have a few ideas and theories about the costs and benefits of group living, but a general explanation has remained elusive. A major obstacle standing in the way of achieving a general explanation is that there are a lack of studies on marine organisms, which is what my study will focus on.

One of the most promising frameworks with which to study this behaviour is the cooperative breeding framework. This framework contains several hypotheses. I’ll go through just a few which I would like to test and which I will refer to throughout the presentation.

1) Ecological constraints – EC looks at a situation where ecological factors force animals into groups. eg. high predator abundance might cause animals to group in order to obtain a protective benefit through the dilution effect or by making use of discrete habitat patches which provide defence.

2) Life-history – LH hypothesis and EC are closely linked. LH hypothesis looks at inherent life-history traits of animals which might lead to a situation where group formation if more beneficial. For example, animals with long life-spans might cause a breeding habitat to become ‘saturated’. i.e. no vacant breeding ground for new recruits to make use of. In this case it might be more beneficial for the next generation of reproductively mature individuals to join a group and wait for the breeding habitat to become available (avoids conflict).

Most of these studies on birds, insects and mammals to date have either been broad phylogenetic comparisons or fine scale experimental manipulations. Both methods have merit and have in fact been responsible for the huge advances in this field, but there are few studies combining the two approaches. It is important to combine these methods as the broad scale studies can draw correlative conclusions across multiple taxa, but they don’t offer causative explanations. Which is where the experimentation becomes important. However, fine scale experimentation can only focus on a few taxa so the results are often difficult to apply generally across multiple taxa.

So how am I going to approach this question?

I will use a genus of coral reef fishes which show considerable variation in social organisation as a model. Gobiodon species are found in high abundance on tropical reefs. There are over 20 known species.

Slide3

I will start by conducting a broad phylogenetic comparison of the Lizard island population of Gobiodon. This will involve making a genetic phylogeny of the species at Lizard Island (the above picture shows the phylogeny of the Red Sea population). Phylogenies show how closely related species are to each other. Species radiating from a common node are more closely related to each other, than to species originating from other nodes. The nodes represent some common ancestor. Looking at where sociality occurs on this phylogeny is important as we can see whether the behaviour arose at a single evolutionary point or whether it has evolved multiple times. Looking at the tree above, social behaviour does appear to have evolved multiple times.

Using this phylogeny as a base, I can map ecological and life history traits of each species. This will show which traits the social species share and which the asocial species have in common with each other. I will use this information to identify traits to manipulate experimentally to try to induce social behaviour in an asocial species or vice-versa.

I have chosen these fishes because they show great variation in social structure. for example G. histrio is stubbornly pair forming like Romeo and Juliet. While G. rivulatus forms large social groups more akin to the Great Gatsby, although I suspect that there might be some reproductive shares going to subordinate individuals in the Great Gatsby…

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But back to Gobiodon; they are also highly site attached, which makes observing and cataloguing their social systems, ecological traits and life history traits far simpler and experimenting logistically easier with them. Once they have chosen a coral to settle in, that is where they stay. Even when the water level drops below their corals during extreme low tides, they will hunker down and remain within the coral, exposed to air for a couple of hours. They have a high hypoxia tolerance and air breathing ability which enables them to do this.

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I have chosen Lizard Island in far north queensland as my study site because:

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a) it has an exclusive resort where celebs like leo can be found. Unfortunately, they don’t let the researchers stay here. They tuck us around the corner in this photo.

 

 

 

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b) most of the species of gobiodon are known to occur here (and possibly a new species). It’s also worth noting the size of these fishes in the picture below. The fish in the second and fourth pictures on the top row are actually sitting on my gloved hand.

 

 

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c) There is a well established research station here run by the Australian Museum which makes field work and experiments much easier.

 

 

We started this work by finding Gobiodon colonies around lizard island and capturing, counting and identifying the species. To capture the fish we use a mixture of clove oil and ethanol which anesthetises the fish and then we ‘waft’ them out of the coral. Once we capture the fish we hold them in plastic bags until the end of the dive and then take them to a boat to be processed.

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To build the genetic phylogeny we need to obtain genetic material. I’ve been taking fin clips from the fish for this. We just snip off about 1/8th of the caudal (tail) fin area while the fish are anesthetised. It’s not uncommon to see these fish with much larger chunks taken out of their fins, usually from conspecific disputes. The fins do grow back quickly so we’re not doing any permanent damage to the fish.

While we have the fish on board and anesthetised, we measure their SL and TL and we give them little tattoos. These are a flourescent elastomer tag inserted under the skin so that we can identify the fish again when we come back in order to determine some life-history traits like dominant turn over rates or growth rates or mortality.

To collect the information about the ecological traits to map onto my phylogeny, I have been seeking out Gobiodon colonies and taking Coral measurements.

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To measure habitat saturation we have been using x-transects centred on a colony of Gobiodon. We move along each axis of the transect and catalogue all of the corals known to be inhabited by Gobiodon species. We record whether they were inhabited or not, what they were inhabited by, how many individuals are in each coral, the size and species of each coral.

This gives us an indication of how many and what types of colonies are surrounding the focal colony and how much available habitat there is in the immediate area.

I need to complete the phylogeny now to map these LH and ecological traits and see if there is any correlation between sociality and these traits.

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The downside to working in beautiful tropical locations is that they are prone to cyclone activity.

Cyclone Ita came right over Lizard Island in April this year. The photos below are taken from the same sites (left to right) before and after the cyclone. In February, my assistants, and I had tagged about 600 individual fish with a plan to come back in 6 months to re-capture and re-measure these individuals and determine growth rates and dominant turn over rates. I returned in August and found 8 of the original 600 tagged fish.

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But moving on, I am still interested in the evolution of social behaviour in these fish, but I will focus more on the evolutionary advantages of sociality or asociality in re-colonising a reef after a disturbance. And I’m hoping that I’ll be able to see that recovery in the data coming out of the x-transects that we’re using to measure habitat saturation.

Anecdotally, there appeared to be more uninhabited corals than there were in February, though I can’t verify this statistically because I used different methods (we were looking at a different question in February). There also appeared to be more juveniles present in August than in February.

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Moving on to some preliminary results, these tables show the results from a statistical method called a Generalized Linear Model or GLM for short. Don’t worry about that or all of the technical looking numbers, all you need to know is that a significant result is indicated in red or a highly significant result in yellow. For most of the species above, there is a significant result for average diameter of the coral. That just means that there was a strong relationship between the size of the coral (the predictor) and the number of individuals living within the coral (the response). i.e. the size of the coral could be used to predict the number of fish living within it for those species with a significant result.

I’ve found that the group size of some of the social Gobiodon species is related to the coral size, but not to the size of the largest individual (alpha), which is interesting as Marian Wong and Pete Buston (who presented at UoW a couple of weeks ago) had found that there was a relationship between both coral size and the size of the alpha with the group size in the anemone fish Amphiprion percula. G. oculolineatus does appear to follow this pattern. What I can take away from this is that the determinant of group size is probably species specific and will therefore be more difficult for me to make general conclusions about.

Looking at some of the before-after cyclone data that was comparable, the corals that did survive the cyclone showed positive growth. However when we looked at the site as a whole, the average size of the corals had decreased. This was to be expected since, as you can imagine, a major disturbance like a cyclone would smash up the larger corals into smaller corals. The smaller corals also have less surface area so are more likely to survive a cyclone.

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I’ve also found that, as you would expect there was a decline in the coral goby abundance. However, the second graph is more interesting. Some species, like G. erythrospilus, G. rivulatus and G. unicolor appear to be occurring in larger groups post-cyclone. This is possibly an indication that they are in a phase of recruitment.

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This will require further exploration so I have another trip planned for January. During this trip I will be re-conducting the x-transects in order to examine this trend across multiple sites. What I will be looking for is whether there is a detectable shift in the goby community. There might be a higher proportion of social species present which could indicate that social species have some kind of advantage in recolonising a reef after a disturbance (or vice-versa).

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I will now need to finish the genetic phylogeny and map on the ecological traits that I have collected so far. I have another round of field work booked in for January. I will be conducting more of the cross transects to see if there has been a detectable community shift since my last visit. I also want to set up a pilot experiment looking at the effects of habitat quality and habitat saturation on a subordinate individual’s decision to move or not.

I would also like to set up and run the life history traits work again. i.e. the capturing and tagging component, as this is a really important part of the cooperative breeding framework which I’d like to explore.

To finish up I’d like to say a final thank you to my assistants for their help in the field. It really is a big commitment for them to come and help me out for weeks at a time. Thank you very much! My work could not happen without your help.

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If anyone has any questions about my project, please leave a comment below. Thank you!

A MADAGASCAN ADVENTURE: Part 1

Part 1: Discovering Madagascar

When my older brother, asked me to write a guest blog I was at first excited and then terribly daunted. I should preface this post with the fact that I am not a scientist, so the following is purely based on the observations of an amateur!

I have been diving since 2005 and have a passion for all things ocean. I also love to travel. After spending the past 6 years behind a desk, I decided to temporarily abandon my Sydney life to spend some time indulging in some underwater delights and a slower pace of life.

So, I’ve recently returned to Australia after months of diving and travelling, including three months living in a remote fishing village, Andavadoake, on the south west coast of Madagascar. I was volunteering with a UK based marine conservation organization, Blue Ventures, who have been working in the area for over 10 years.

01 Madagascar-map-02

I have wanted to visit Madagascar for many years after seeing an image of the Allée des Baobab in a travel magazine as a teenager. And who doesn’t want to see lemurs in the wild?! However, it was with naivety that I embarked upon this adventure knowing very little about the country and its people, not to mention the extensive reef system – one of the largest in the world! All I knew was that I would be diving everyday (win), and would learn some science to help monitor the local reefs (win)… AND I would be there during whale season (WIN).

Humpbacks passing by. Photo by Sam Blyth

Humpbacks passing by. Photo by Sam Blyth

What I quickly learned was that Madagascar is not a country filled with primordial rainforest and troops of lemur bouncing around, but a country of varying climate and terrains. I drove through endless rice paddies and farmland reminiscent of my travels in South East Asia; vast rocky scapes that hold minerals and precious gems; the desert spiny forests full of the famous octopus tree; and finally, the turquoise, sparkling ocean. It was surprising and sad at times, knowing that much of this land, in fact, used to be primordial rainforest, but that’s perhaps, a discussion for another time.

Farmland in central Madagascar

Farmland in central Madagascar

Rocky scapes

Rocky scapes

Turquoise waters of Salary

Turquoise waters of Salary

I arrived in Andava with my fellow volunteers right on sunset, having travelled four days overland. We were a little disheveled yet full of excitement from our first experiences in Madagascar, which involved descending from the central plateau by hazard lights as our headlights didn’t work; a crazy Chinese hotel where we struggled to find our rooms in the labyrinth of corridors; lemur, chameleon and scorpion sightings; a flat tyre; hiking desert canyons; swimming in freezing pools in small oasis’; our first taste of Malagasy rum and dancing; incredibly rough ‘paved’ and unpaved roads; and more lemurs!

Hiking the canyons of Isalo

Hiking the desert canyons of Isalo

But finally, we were standing on the beach and gazing at the sun as it dipped into the ocean for our first (of many) Andava sunset. I rarely missed a sunset after that, as my thousands of photos suggest. This would become one of my favourite parts of the day.

First sunset in Andavadoake

First sunset in Andavadoake

In my next post, I will delve into my time as a volunteer diver in the village of Andavadoake…

I won a competition!

Woohoo! Just thought I’d share this great news. I don’t win things very often, usually because I don’t enter, but this time I thought I’d throw my hat in the ring and now I’m the proud owner of a copy of Aaron Wong’s new photobook, “The Blue Within”. I din’t win the big prize of a free trip on board one of the Siren fleet boats, but my photo took out the month of May competition. I’m pretty chuffed 🙂

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Back in May this year, my partner and I went on a live-aboard dive trip in Indonesia on board the SY Indo Siren. On board I saw that they were accepting photographs for a competition. I only have a GoPro, which I’ll admit doesn’t generally take award winning photographs. I’ll also admit that I am a complete hack when it comes to any sort of photography. I know the photos I like and dislike, but otherwise words like “composition”, “F-stop”, “aperture” and “focal length” are pretty lost on me.

But, I liked this photo. So I submitted it and apparently the lovely folks at Worldwide Dive and Sail also liked it. Thanks guys!

Lizard Log 31/8/14 – 4/9/14

Apologies for the slight delay in getting this post up. We’ve been hanging out with a good mate in Townsville for the last few days. Whilst there we did a dive on the SS. Yongala.

Diving the SS. Yongala off Townsville.

Diving the SS. Yongala off Townsville.

Without further ado, the final Lizard Log for this field trip.

Day 30 31/8/14

The wind had dropped quite a bit today which was a great relief. We were able to get out to the Palfrey reef system, near Horseshoe reef today. It was shallow, but clear and the sun was shining so it was quite pleasant. We got heaps of transects done on our first dive.

On our second dive we moved to Big Vickey’s reef where we came across three of my tagged corals. Unfortunately one of them was completely dead and covered in algae. The other two were intact and even contained the same tagged fish from last time. Great news, but sadly, still not enough to run any meaningful analysis.

We removed the old tags once we'd made our measurements.

We removed the old tags once we’d made our measurements.

In the evening, Kylie and I packed a picnic box and wandered up the beach for sunset. One of the resident seagulls waddled after us and kept us company. I quite like this particular seagull as it keeps all the other gulls away. We enjoyed a couple of sunset beers and a whole heap of chips and dips.

 Day 31 1/9/14

First day of Spring! We dived another part of the Palfrey reef system today. It was much shallower than our dives yesterday, so it was difficult to spot the gobies. We went over to Palfrey Island for our surface interval. As we were walking in over the sand bar, we saw a little black tip reef shark cruising the shoreline. It disappeared pretty quickly when it saw us though.

We had the Bshari lab group over tonight for a pizza night. I really enjoy their company. I had a good chat to one of the researchers about my PhD. It was really reassuring to hear his perspective, looking back at their own experience.

Day 32 2/9/14

Last day of work diving today. I was pretty happy to be finishing up honestly. It’s nice diving in warm water, but the surface conditions have been pretty tough this time around. We dived at Loomis reef today, which I’ve never been to before. It was in really good condition with huge heads of acroporid corals scattered throughout the reef. I was expecting to see some big groups of gobies in these corals, but most of the gobies were still only in pairs. When we did our surveys in February, we found that the group sizes for the social species, were related to the coral size. This doesn’t seem to be the case this time. I suspect that the population is in recovery after the cyclone, but only time will tell.

We went to, the station managers house for dinner tonight. It was a lovely evening with lots of laughs. They cooked up a blue fin trevalley that they caught yesterday. When he caught the fish though, he spiked himself on the lure and had to go to the clinic over at the resort to get it removed!

Day 33 3/9/14

Kylie and I went out for a fun dive this morning. We fly out tomorrow afternoon so we decided to squeeze in a dive before our 24 hour no-fly limit kicks in. The wind was really low today and Lyle said that we might be able to dive at Coconut Beach. We went out around Lizard Head to check out the conditions. It would have been fine for a dive, but the regulations prohibit us from diving without a boat watch person if the swell is over half a metre. It was definitely getting close to that limit and the conditions were predicted to deteriorate in the afternoon, so we decided to play it safe and head back to Big Vickey’s for a dive. We anchored up on the western side of the reef and jumped in. It was lovely to be diving deeper the two metres. We saw quite a few nudibranchs and flatworms, but not many fish. We were just happy to be in the water diving without having to record anything.

Nudibranch

Nudibranch

We’re winding up now, just going through all the cleaning and finalising paperwork etc. It’s always a little sad to be leaving this place. I love meeting all the researchers here and the social scene is great. But I am ready to go home.

Day 34 4/9/14

It was our last day on the Island today. We decided to kick it off by climbing Cook’s Look, the highest peak on Lizard Island. We set out early from the station and made it to the top in about an hour. We stopped several time to admire the views as we climbed higher and higher. The walk heads out along the ridge to the north of Watson’s Bay and then turns back towards and up the main peak. It was quite steep in places, but the view from the top was beautiful! It would be interesting to do the walk again but later in the day as the sun in the morning reflects off the water in the east and you can’t see the ribbon reefs. It would make for a really hot climb though.

Kylie admiring the view

Kylie admiring the view

After getting back to the station we finished our clean up duties including pulling the boat out and giving it a wash down. We found out that our plane was actually scheduled 2 hours earlier than we’d thought, but that was fine as we’d done most of our cleaning the previous afternoon.

We made our way around the station in the afternoon to say our farewells and then got picked up and taken to the airport. Unfortunately, some of the workmen from the resort were held up and our plane was delayed by about an hour. We were entertained a couple of times by Bruce driving past on the station tractor and blowing kisses at us! We finally boarded the plane and lifted off, passing over the blue waters and patch reefs of Lizard Island.

Flying out

Flying out

It has been a rough (weather wise) trip but reasonably successful. We didn’t get the information we wanted, but I was expecting that. Our plan B worked well though. I now just need to sit down and analyse the data. Thank you to everyone on Lizard Island for making our trip not only successful, but, just as importantly, FUN! A special thank you to Anne and Lyle, the station directors, and Maryanne, Lance, Cassie and Bruce. You guys do a fantastic job of keeping the station operational and creating a great atmosphere there. And you make it look easy! We look forward to seeing you all next trip!