Chagos Conservation Trust


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Feb 2012 EXPEDITION Blog Jump to project background

  • About the expedition

    Anne SheppardBetween 13th February and 7th March 2012 a scientific research expedition took place in the Chagos archipelago (British Indian Ocean Territory), supported and facilitated by the Foreign and Commonwealth Office and numerous other institutions. Twelve scientists and supporting team members participated in the first full scientific expedition since the no-take marine protected area (MPA) was established in April 2010. Our research plans therefore prioritised the continuation of long-term monitoring programmes as well as establishing the best and most resource-efficient methods to monitor and manage the MPA. We believe our initiatives will assist BIOT in understanding and managing the world’s largest fully no-take MPA, maintaining this extraordinarily rich area of marine and terrestrial biodiversity.

    For more information you can download the expedition summary document from our Resources page. You can also download the expedition report to read about what we found.

    Aside from guest contributions, the below posts were written and edited by Anne Sheppard, Research Fellow at the University of Warwick and Editor of Chagos News.

  • Day 17 - Final thoughts

    Corals at South Brother islandAs we finish packing of samples, decommissioning of equipment and storing all our bits and pieces, we are already planning the next scientific expedition out here.  There is so much to be done in this natural laboratory, and we all feel a great sense of responsibility in making sure Chagos continues to be such an important resource for humanity; and this isn’t  overstating it or being over-sentimental.

    Some of us have been working on Chagos reefs for many years now, and have visited several times.  Some of us are here for the first time.  All of us are inspired by the place, and the delighted, often incredulous reaction of scientists on their first dives here reinforces in all our minds how extraordinary this place is.  How many ways are there to say “Wow!” ?
     
    But thirty years ago Chagos was perhaps no more special than very many reefs nations around the world.  The islands in Chagos at that time had only recently been vacated and still suffered from the effects of human impacts like so many places, and thirty years ago we saw so few turtles and coconut crabs, for example.  And then the massive mortality from ocean warming occurred in 1998 which affected Chagos’ reefs as much as any other place in this ocean.  Now though, Chagos reefs have recovered to as close to pre-impact condition as anywhere can get, and being one of the very few places in the world which is uninhabited over most of its extent, turtles, coconut crabs and birds are recovering well and some are extremely abundant again, having had the chance to recover.  Regarding reefs, people dive in some wonderful places in the world and feel that they are seeing unspoiled reefs.  But how can we say what an unspoiled reef looks like?  There is a phenomenon called the ‘shifting baseline syndrome’, where the best conditions that a researcher has seen, or knows of, tends to become the standard reference point for what a ‘good’ or ‘unspoiled’ site should look like.  But very few new researchers in the world now are able to see what a truly unspoiled reef should be like, and this is one of the very valuable roles that Chagos plays.  It is a priceless reminder to us all what we are missing and which, with a global population of 7 billion, we are unlikely to regain anywhere else in the world anytime soon.  Unless we take more action…

    Our international team of scientists agree, the Chagos Marine Reserve is globally significant and deserves international support as the world’s biggest no-take MPA.

    Birds at Middle Brother islandPete Carr, University of Warwick, UK
    Pascaline Cotte, Trainee scientist
    Nick Graham, James Cook University, Australia
    Catherine Head, Oxford University, UK
    Heather Koldewey, Zoological Society of London, UK
    Tom LeTissier, University of Western Australia, Australia
    Bob Long, expedition doctor
    Jessica Meeuwig, University of Western Australia, Australia
    Pete Raines, Chagos Conservation Trust, UK
    Anne Sheppard, University of Warwick, UK
    Charles Sheppard, University of Warwick, UK
    David Tickler, Bertarelli Foundation

     

  • Day 16 - One day before the last...

    Endemic Chagos Brain CoralWe head off to work in the morning.  The dive boats skim across crystal clear waters, teaming with fish, as we near the reef a large school of spinner dolphins join us, jumping ahead of our bow wave.  Overhead a huge flock of Red-footed Boobies, Frigate birds and many species of Tern flock in the warming air.  We enter the water and the huge schools of fish obscure the reef.  Another day’s work on one of the most marvellous reefs in the world awaits us.

    This afternoon Pascaline will complete the next stage in her dive training.  All the expedition members are very impressed with how much she has helped us all with our work.  It can’t have been easy for her, being so much younger and a far less experienced diver, but she has been superb.

    Tomorrow is our last day’s diving, no diving the day before we fly out.  All the scientists are pleased with the amount of data that they have been able to collect.  A very successful expedition.

    Expedition leader Charles Sheppard sums up.

    Pascaline surveying reefs“As with previous expeditions, scientists taking part mostly have two kinds of things they want to do: firstly the “must do” tasks such as monitoring for BIOT’s management purposes, and a second “nice if we could do” list, which would advance the science of the place. Again, with the huge support of the officers and crew of the BIOT Patrol Ship, the Pacific Marlin, I think most of us have made huge inroads into the second list as well as completing the first. We have squeezed a quart into a pint pot thanks to the help we have had from all quarters. Furthermore, we are delighted that two people accompanying us have been fired up to join university Masters courses in subjects related to protecting Chagos, while a third, Pascaline, our Chagossian colleague, has also been stimulated to take a degree in marine biology, in order eventually to continue the work in understanding how Chagos functions as an intact ecosystem and how best to help ensure it stays in such a good condition.This time, we have seen again that these reefs and some rat-free islands are in superb condition, many aspects of which are even better than ever. For probably all of us there is nowhere quite like it. It needs to stay in the condition it is in today.”

    The expedition has been declared a resounding success by all members of the team.  Much of this is due to the incredible support that the Pacific Marlin and her exceptional crew have given us.   I hope that you have enjoyed following our expedition and support this, the biggest of the world’s no-take Marine Protected Areas

    With best wishes

    Anne Sheppard
    Chagos 2012 team member

  • Day 15 - More about BRUVs

    Recording Coral CoverWe sadly left the northern atolls behind today.  Today belonged to the BRUVers.

    The  Pacific Marlin set sail south, heading for some isolated seamounts just to the north of Diego Garcia.  The top of these seamounts are around 70-90 metres deep, so the diving teams have a much appreciated day off. 

    Jessica tells the story -

    “We left Egmont overnight for what the charts suggest is a field of shallow seamounts, rising from 1000m to less than 100m from the surface, to the northwest of Diego Garcia. We have identified four candidates that rise to between 63m and 94m of the surface ... but we’re not sure they are actually there!  We arrive at the first waypoint at dawn with the Marlin running a search pattern over the area.  Anticipation turns to quiet disappointment as we are unable to find it. But determined, we move to the next location.  Eyes still glued to the echosounder, pinging to 800m, there is a whoop of excitement on the bridge as we start to see the bottom shoaling.  Moving at 2.5 knots, we see in rapid succession 800m, 500m, 200m and then a plateau at about 65m.  We mobilise long ropes, the BRUV rigs and begin dropping across the plateau from the FRC (Fast Rescue Craft) which has been our workhorse throughout this trip in the able hands of Chief Engineer Les Swart.

    Twelve BRUV deployments later, with our brawny but exhausted crew having hauled the BRUVS up from between 65m to 85m on a beautifully still but swelteringly hot day, the depths were revealed.  Crystal clear bright water greeted us even at 85m.  The top of this seamount hosted a garden of seawhips, soft corals, and sponges.  Inquisitive silvertip sharks were abundant, a large marbled ray ambushed one of our bait bags, and an abundance of emperors crowded the field of view, with trevally swooshing through.  Moorish idols, pennants flying, danced in and out, undisturbed by so many potential predators.  Our dive master David Tickler also completed a very quick blue-water snorkel which yielded a magnificent photo of six silvertip sharks suspended in a rich blue.  We are very excited about finding this feature as a preliminary assessment suggests it has not been trawled and, according to our Senior Fisheries Protection Officer Andy Deary, its proximity to Diego Garcia means poaching is unlikely.  A perfect place to study pristine fish and shark assemblages!

    Fish around Middle Brother island Meanwhile, Captain Neil Sandes had spent the BRUVing time going in circles, literally.  He mapped the 100 km contour, indicating a maximum length of about 2.2km and a maximum width of 1.2km.  In recognition of the honour of this accomplishment, we have named it Sandes Seamount (subject no doubt to all sorts of international rules of course!).

    We then sailed on to find the remaining two seamounts on our list.  Both were found by ornithologist Peter Carr using seabirds to help guide us onto the features.  Waypoints were taken but camera deployments would have to wait for another day as the sun was starting to set.  We continued our return to Diego Garcia, accompanied by 11 bottlenose dolphins playing off the Marlin’s bow.  We couldn’t help but reflect that the day had been a magnificent one of exploration and discovery.”

    Late in the evening we sailed into harbour in Diego Garcia, all of us enjoying the first sheltered waters in several days.  It feels like the expedition is over but we still have 3 days of work to do on Diego Garcia.

  • Day 14 - Danger Island

    Salomons Anglaise PassToday was the last diving day in the northern atolls of Chagos.  Tomorrow we will spend the day using the BRUV units on some deeper seamounts just to the north of Diego Garcia.

    In the morning a group landed on Danger Island.  This was a very difficult landing as Danger has a very steep beach and was surrounded by crashing waves.  This meant that we had to jump from the inflatables and swim through the surf onto the beach.  A very strong undertow, caused by water pouring over the reef and out through the channel that we were using to swim to the shore, made the access very hard work and a couple of us were unable to swim against the strong current and so had to turn back and return to the boat which was hovering off to make sure we all landed safely.

    Danger Island is a small island and, like Nelsons Island, one of the more remote and isolated islands, it has a good stand of very healthy native hardwood trees, especially Pisonia, as it was never cultivated during the plantation days.  Possibly due to the difficulty of landing on it!  The question of how Danger Island got its name is always asked and other than the possibility of it being to do with the difficulty in landing, no one knows.  The healthy and significant bird community on Danger is thriving well.

    Another group dived on a shallow offshore bank which, on the last expedition,  was discovered to be covered with seagrass.  There is always the hope out here that we will discover dugongs, these large seagrass eating mammals, after all one island in the group is called Sea Cow, another name for the dugong, and one is called Vache Marin, Sea Cow in French.  We didn’t see any today but there is a lot of the Great Chagos Bank still to explore.

    In the afternoon we moved south to Egmont Atoll where one dive team recovered more temperature data loggers that had been positioned on previous expeditions and replaced them with new loggers.  More cores from a large coral head were taken to allow the calibration of the logger data with the palaeoclimatic data collected on a previous expedition.  The second dive group were again collecting data from transects surrounding four more dead coral heads, which are being collected to analyse the communities which inhabit them as part of an international study.

    Throughout the day the BRUVers were busy deploying units.  Tom Letessier tells the story.

    “We are now nearing the end of our expedition, and from a BRUVing perspective, it has been a resounding success.  We have conducted over 175 camera deployments, giving unprecedented insights into the Chagos reefs and fish ecology.  Our collection amounts to over 350 hours of film, which will be used for species identification, estimates of the relative numbers of fish, and size measurement, important variables in ecology.

    The support we have received from the master, officers, and crew of the Marlin in conducting our activities has been extraordinary.  Long hours, heavy seas, equipment failures, demanding scientists, nothing has affected the good mood or the daily running of the ship.  Today for example, the chief engineer Les and his team spent the better part of the morning AND the evening fixing the engine of the ships Fast Rescue Crafts, enabling us to get 16 camera drops in during the afternoon.

    Tomorrow will be our final day at sea, and will perhaps bring our greatest challenge yet!  We hope to deploy BRUVs on shallow seamounts situated on our last leg to Diego Garcia.  The prospect of sampling at 100 m depth is exciting, but will provide some interesting challenges, similar to landing an aircraft in a Swiss airport.  These mounts are very easy to miss, and are apparently needle sized! Wish us luck.”

    Tomorrow I will report on their success!

  • Day 13 - Thoughts from Pascaline

    DivingThe strong winds are starting to take a toll on the divers.  So far it hasn’t stopped any work yet but heavy sea conditions have made what is normally a fairly effortless task into hard work, and one data logger located in a storm corner of reef was left because the sea was too rough for safety.  Yesterday morning a short squall with over 40 knot winds made for an extremely uncomfortable  period for the surface team who huddled in the wind and rain.  When the divers surfaced at the end of the squall, all smiles and comments about how rich the coral was, they were surprised to see some miserable faces greet them.  In the afternoon, a trip to the seaward side of Eagle Island had to be abandoned before we got there due to very high waves making it potentially dangerous.  However a reserve site in the lagoon proved to be very rich in species some of us were sampling.

    In Eagle Island, we also found and area which is undergoing an outbreak of Crown of Thorns starfish (COTs).  There is a large area of dead Acropora coral, which are COTs favourite food.  That which was dead for some weeks is covered in algae, while that which is recently dead is bleached pure white, and among these newly dead bleached patches we found aggregations of about 20 COTs per m2.   We took the opportunity to map the area affected and found that it fortunately goes only half way down Eagle Island rather than covering its entire coast.  Expedition doctor Bob Long made a manta board and was towed along the length of Eagle Island; as a result the heavily impacted area has been mapped along with the approach front of the outbreak and the as yet unimpacted area.  We have taken several GPS coordinates to plot the boundaries of the area so we can look to check on extent of damage and recovery sometime in the future.  Usually these outbreaks are completely natural, and being a healthy reef system, we predict that the corals here will bounce back in a short time, given that there are no other stressors acting on the reefs here.

    One dive team caused a lot of envy amongst the rest of us by seeing a sailfish swim by.  It was about 2 metres long and swam past only about 10 metres away from the divers.  We will post the picture of it when we return to Diego Garcia.

    In the evenings we are continuing the Pacific Marlin Seminar Series (rated by some to be on a par with far grander lecture series!) which started with the expedition in 2006.  After the evening briefing, each scientist gives a short presentation on their research.  As we are a collection of scientists from all over the world and working on a variety of topics, we have a lot to learn from each other.  This exchange of information is very important and already several cross disciplinary research ideas have been discussed.

    As well as being a collection of scientists from around the world, we also have a young trainee member of our team.  Pascaline Cotte is 19 years old and is of Chagossian descent, her grandfather was born on Ile du Coin, Peros Banhos atoll.  Pascaline was a Chagos Conservation Trust scholar on a recent Coral Cay Conservation programme in Tobago, where she learnt to dive and learnt the basics of conservation monitoring and took part in a monitoring programme out there. 

    Pascaline tells of her thoughts on the Chagos MPA and being a member of this expedition:

    “The MPA, it’s not just good for Chagos but for everyone else too.  It’s good to have an example of how other places should be – to know if your place is good or bad.  I’m for the MPA, it means no fishing in Chagos, keeping the place good.  Places like Chagos are rare.

    I feel privileged to be here. Being a member of this expedition is overwhelming because having the chance to work along such experienced scientists at an early stage of my career is a great opportunity for me. Each day I learn a whole new thing.  There’s a lot more going on than I expected and it’s been going on longer than I knew.

    Also being on Chagos is inspiring because it gives me the opportunity to see the islands of my ancestors, something not all Chagossians can do.

    The Chagossian community have mixed views of me being here. Lots of people I didn’t know, knew that I was coming here and asked me about it. Many think it’s for a holiday. I don’t really follow any political views and I don’t speak for anyone. I personally think that there needs to be a raised awareness of the work being done here. I’m very happy to see some heads in the community supporting the MPA. Allen Vincatassin does and I would very much like to see much more people in the Chagossian community supporting it and not to see it as a barrier to this place but a gateway instead.

    Being on Tobago with Coral Cay gave me an idea what I want to do and being here confirmed it. When I get back to England I will do my ‘A’ level Biology and then I hope to go to Uni to do Marine Biology and in the future I might do research out here.”

  • Day 12 - The Three Brothers

    Middle BrotherThe Three Brothers islands on the Great Chagos Bank and a magical place filled with more birds than you would think could fit on the tiny islands. On Middle Brother, a beautiful island with its own large lagoon, at least twenty five thousand Sooty Terns were nesting, as well as Noddy Terns and Red-Footed Boobies. On North Brother, a more challenging island to land on, thousands of Wedge-Tailed Shearwater had nesting burrows in every suitable space on the ground that they could - except for that occupied by the ground-nesting Brown Boobies.

    These illustrate how important unspoilt islands are for these birds, as, being ground nesters, they would be completely vulnerable to rats, cats, dogs and of course man. The islands also illustrate another point raised by the expedition ornithologist Pete Carr, that Important Bird Areas (IBAs), of which Chagos has ten, should encompass not single islands but groups of islands. South Brother normally has ten thousand pairs of nesting Sooty Terns, but this year they all seem to have moved to Middle Brother to nest. South Brother this year has no significant numbers of sooty terns nesting on it at the moment, therefore. It would still retain its IBA status, but if the group of islets collectively were one ‘IBA cluster’ then that would make more sense over the years and would cater for such movements.

    But I’m getting ahead of myself.

    North Brother SeabirdsThis morning we all dived on the seaward slope off Middle Brother. The water was clear and the dive teams were surrounded by literally thousands and thousands of fish called Rainbow Runners. It was a magnificent sight. The same sorts of recording was done as we have done on several other reefs now, all to build up the amount of data to statistically useful levels.

    The BRUVS team were deploying the units to the north of North Brother, well away from the divers, where today and tomorrow mornings they are looking for any difference between using baited versus unbaited units.

    In the afternoon two teams worked again on the seaward site and one team dived in the Middle Brother lagoon, more murky and sedimented, but very different to any other known site in this archipelago in terms of its corals and other reef life. This is an interesting location, with four eagle rays, a very large stingray and several large nurse sharks on this occasion. Close to shore, two baby blacktip reef sharks swam by and the divers were again engulfed in a huge school of jacks.

    After surfacing we went ashore to photo document the incredible numbers of birds on the islands and the skies above them.

  • Day 11 - Victory Bank

    Fish and Sea Fans at Barton PointOn our way to the Three Brothers – the islands on the Great Chagos Bank where we will be working next – we returned and spent the day on Victory Bank, where the BRUVers needed to do some more sampling. The divers who wanted to had an early dive to do their work, in order to be out of the water before the BRUVs were deployed and attracted their large toothed clients. The rest of us used the day to catch up with data entry and some preliminary analyses. These analyses show that the coral continues to recover, particularly in deeper water where it had lagged behind the shallower depths. Also, the surgeonfish habituation studies, which are looking at responses to diver approach in fished, lightly fished and marine protected areas throughout the Indo-Pacific region, show that in Chagos, divers can approach to about 35% closer than even in other marine protected areas.

    The dive was spectacular, very good visibility, schools of huge fish and a very large nurse shark which almost swam into the divers – resulting in a superb photo by David which will be posted as soon as we get back to Diego Garcia and a normal internet link.

    The BRUVS work is going very well and Jessica takes on the story from here.


    Victory Bank – a small submerged atoll rising from 100’s of metres to 5 m. It measures approximately 6 km x 4 km, a perfect oval of coral surrounding a lagoon with reported depths of 33m. Last surveyed in 1837 when its depths were plumbed by leadline, Victory Bank’s most recent research consisted of several exploratory dives by the intrepid Professor Sheppard in 1979. As part of this expedition, the Pacific Marlin’s Captain Neil Sandes carefully navigated the entrance to the lagoon on the 21st of February. We think the Marlin is probably the first ship to ever anchor inside the lagoon! We then dropped our baited remote underwater video systems (BRUVS) at eight locations distributed around the submerged rim of the atoll. On retrieval, we found several of our bait bags shredded. A quick review of the footage found that a beautiful young tiger shark, stripes blazing, and a rather large nurse shark were the culprits. Crystal clear water and shoaling fish had us determined to return. So on the divers’ rest day, 25th of February, we anchored on Victory Bank at 07:30. A morning shallow dive provided us with a fish-eye view of the seascape as a whole. The coral studded rim dropping off precipitously into the deep blue, with the shoulders of the atoll home not only to corals but large school of snapper and fusiliers, silvertip and grey reef sharks, and a very curious nurse shark. We then spent the rest of the day dropping BRUVS in the lagoon of the atoll down to 40m and repeating samples on the rim. Combined, this footage will provide us with a quantitative understanding of the fish assemblages of this very isolated and pristine submerged atoll. To learn what constitutes unexploited fish communities in both the shallow and deep areas of these atolls provides us with an essential reference point to understand the impacts of human activities on coral reef ecosystems ... and is why it is so important that the Chagos has been protected as a no-take marine reserve.

    We promise to make clips of the BRUV videos available on the website at a future date!

    Nick, Pascaline and Bob had an encounter which made everyone extremely envious; they saw the first whale shark observed underwater in Chagos. According to Nick, it was only a small one, but at about five metres long still a heart stopping sight. Again, the curse of the working marine biologist had Charles and Anne with heads down recording the coral cover and missing it swimming over their heads.

    Late afternoon we had a fairly bumpy journey over to the Three Brothers. The anchorage here is fairly exposed to the wind and sea so we hope it will settle soon.

  • Day 10 - Last day at Peros Banhos

    Bob Long lays tapeThis was our last day at Peros Banhos before we move onto the islands of the Great Chagos Bank.

    A typical day, divers set off in the morning at 8am.  Two teams went to the seaward reefs, a trip of about forty minutes in choppy seas, to continue various fish behaviour studies in undisturbed locations, and shark abundance counts.while others collected more lumps of old, dead coral colonies to extend their studies on the cryptic communities which, until now, have been an under-researched area of work. It is a point not usually appreciated, but the high diversity of small animals hidden or burrowing in the fabric of the reef is all-important, to biodiversity, reef productivity and food chains and to natural erosion and consolidation of the reef itself. The other dive team went to a knoll in the lagoon to recover the data logger that has been recording the water temperature at two hourly intervals since being placed two years ago; this extends for another two years this series of temperature recordings which started in early 2006. It is very satisfying when the marking stake is spotted and the LED light on the little instrument is seen to be still flashing, showing that its battery is still functioning and it clearly has not been damaged or filled with water! At the same time the island party surveyed the rest of the islands to continue the bird and vegetation mapping. And, as every day, the Pacific Marlin’s RIB took the BRUV team (fairly obviously we call them the bruvers) out to place and recover more of their underwater photography units.

    TubewormIn the afternoon two dive parties again went to the seaward reefs to a slightly different site, to continue work that they were doing in the morning with the fish work this afternoon being parrotfish sex change studies and hawkfish habitat use studies. The lagoon dive team returned to the site where the temperature logger was replaced to drill three short coral cores for palaeoclimatic research.  By analysing the cores, past years’ temperatures can be deduced, and these will be compared with the temperature data actually recorded by the instrument to aid with calibration.  Also, we collected tissue samples for DNA research into Indo-Pacific connectivity, and the samples will be sent to collaborating colleagues in different countries who have requested them. The bruvers continued to place their units. To date they have made over one hundred ‘drops’, producing about two hundred and twenty hours of video footage down to forty five metres deep. In Peros Banhos lagoon they saw beautiful coral gardens at forty metres deep and huge one and a half metre long grouper.

    At the end of a dive, divers usually to do a three minute safety stop at five metres depth, often while hanging on to the anchor line. Entertainment during this compulsory ‘hanging around’ can consist of watching the other divers, watching the fish, hopefully not watching the sharks, but this afternoon for one dive team it consisted of watching a grouper and a moray eel fighting for the attentions of a cleaner wrasse.  These little fish clean the larger fish of various parasites, much like the oxpecker bird does for rhinos in the savannah. We had always believed the rather nice idea that the various fish called a truce at the cleaning station and queued for the cleaner wrasse’s attentions. But not these two, the two metre long moray came out from under a coral table and the cleaner wrasse started to clean it’s teeth, but it was closely followed by the large grouper, which parked itself slightly in front of the moray’s nose and, by ‘quivering’, attracted the attention of the cleaner wrasse which started to clean the grouper’s scales. The moray then did a dash around to the front and got the attention of the cleaner wrasse again. They both leapfrogged each other several times when the moray disappeared under a coral leaving the grouper victorious.

    Processing SamplesLate afternoon the intrepid land party landed on Gunner’s Coin, a very small rocky islet out on the rim of the atoll. There is no sandy beach for an easy landing here, the waves constantly crash onto the rocky shore so getting ashore involves letting yourself be thrown onto the rocks and clinging on for dear life as the surge pulls back, and then quickly scampering out of the way of the next wave. Not for the feint hearted.  They counted four nests of Masked Boobies, these are the least common of the boobies which occur in Chagos and only nest here and a similar rocky islet on the Great Chagos Bank. The nesting numbers of these birds vary from month to month and year to year, showing just how little we know about their breeding behaviour. There were also seventy recently used Wedge-tailed Shearwater nests.  This rocky islet looks un unlikely place for any breeding bird but it is a necessary habitat for some species.

  • Day 9 - Boobie Sightings

    Red Footed BoobieWind and moderately heavy seas the past couple of days have made heavy work of the diving and BRUV deployment.  But this morning we woke to a calm Peros Banhos lagoon, and working underwater this morning was a real pleasure.   It has been said that we need some difficult days to make us appreciate the good ones.

    The exciting discovery today is that Red-footed Boobies are now breeding in the western islands of Peros Banhos atoll. We saw some nests with juveniles in the Scaevola bushes on Ile Diamant, the northernmost of the long western chain of islands in the atoll, and a very surprising 23 on Ile Petite Mapou two islands south. Similarly to the islands of Salomons Atoll, these birds have not been recorded here since at least 1996, when the first survey was done. We hope to find that they might be nesting on more of the islands as we head south down the chain tomorrow.

    The varied science schedule has meant some very active manoeuvring backwards and forwards for Neil Sandes and the Pacific Marlin. The crew continue to give more than you could ever reasonably expect and Les Swart has been nicknamed Gandalf for his magician-like skills in producing fixes and improvements on equipment.

    Today a small group of us (Charles, Pete Carr and Heather) took the opportunity to go ashore on Moresby Island to visit the mangrove forest that was only discovered two years ago by two of the current expedition members (Pete Carr and Anne Sheppard) with Colin Clubbe from Kew Gardens. We had to walk around half the island on the ancient fossil reef flats, trying to avoid the moray eels that were hunting for crabs and seemed quite interested in our feet. Charles and Heather tried to find their way into the forest at a couple of points without success and were driven back by the dense vegetation and lack of mangroves! Luckily Pete then arrived and navigated us swiftly to the centre of the island and the mangrove forest. This is one of only two islands in the entire archipelago that has mangroves, the other being Eagle Island. There is only one mangrove species in Chagos (Lumnitzera racemosa) that unfortunately is under threat from the encroaching coconut palms. This was evident from our visit today with little sign of mangrove seedlings, and in the areas you would expect to see these young plants the ground was covered with rotting coconuts and fallen palm leaves. Pete spent the rest of the afternoon mapping the entire forest with his GPS in order to document the extent of this area for the very first time. The mangroves were stunning and in flower, with nesting red-foot boobies in the trees. Charles and Heather headed back to the Pacific Marlin to prepare for the afternoon dive and en route came across a pod of about 100 bottlenose dolphins which thoroughly enjoyed leaping around the boat for about 15 minutes before we reluctantly headed back.

  • Day 8 - Birds galore

    Red-footed booby We awoke around 4:30 this morning with the clanking of the anchor being raised. Those of us who were lucky were able to get back to sleep for another couple of hours.  After breakfast we arrived at Nelsons Island, the most isolated island, perched on the northern rim of the Great Chagos Bank.

    Nelsons Island was never inhabited.  People came from the other atolls only to collect birds, turtles and the eggs of both groups, and so for that reason there are no rats. Instead there are thousands of birds.

    Pete Carr, the expedition ornithologist was very enthusiastic about getting onto the island to continue his ongoing monitoring of the spectacular bird populations.  He was first in line waiting for the RIB to take us ashore.  Well not quite ashore, it was low tide, with fairly rough sea conditions,  and the island is surrounded by reef.  We had to jump into the water and swim 20 metres or so onto the reef and fight our way through the surf into shallow water.

    But it was worth it, Pete Carr takes on the story from here:

    Tuesday was a non-diving day for the divers and the first visit to an island that was known to be rat free and categorised as an IUCN Important Bird Area – Nelsons Island.  After a challenging swim ashore that involved navigating over the island’s reef fringe, research and monitoring was undertaken of the birds.

    Nelsons is a unique island in the Chagos.  Only two species of tree have colonised the island, Pisonia and Coconut and both appear to have arrived naturally, the vast remainder of the island is covered by the shrubs Scaveola and Argusia.  This has brought about the unusual circumstances of Red-footed Booby breeding in coconut trees in some numbers - this is the only island in the Chagos where this occurs.  (Possibly Nelsons is younger than other islands and other tree species have not yet arrived, boobies breed on what is available and this is a view of a Chagos island 10,000 years ago?).

    Lesser noddy nesting

    The island remains in excellent health.  Lesser Noddy breeding numbers are equivalent to what they were in 1996 and both Red-footed and Brown Booby breeding populations are at a record high.This is of particular importance because in the Indian Ocean as a whole, the populations of boobies are crashing. Of concern is the fact that Brown Noddy has still not been found to be breeding in numbers anywhere near their high of 1996.Even though the sky was overcast and some precipitation fell, the beautiful endemic subspecies of Meadow Argus butterfly managed to put in a few brief appearances.

    After returning to the Pacific Marlin, we sailed to the submerged atoll of Victory Bank, where Tom and Jessica deployed several of the BRUV units.  A description of that will be in tomorrow’s blog, when they have had time to download the footage

    In the evening we continued on to Peros Banhos atoll, where we will be diving for the next three days.

  • Day 7 - Stormy weather

    Perfect corals in Chagos

    The good weather of the past week looks like it might be over for a day or two at least, the wind is certainly up and the seas are significantly higher.  This makes our work much harder, from loading equipment from the ship onto the inflatables, getting over the reef, and being bounced up and down when working in shallow sites.

    As with all expeditions like this, we are trying to pack the proverbial quart into a pint pot, and any delays can play havoc with the schedule.  We have deliberately kept a flexible schedule as it is sometimes difficult to predict how much you will be able to achieve on a dive.  If there is a strong current for example, or if some piece of equipment fails or, as might happen here, the weather changes, then parts of the work need to be trimmed to suit.  We are packing things in as efficiently as we can just in case of any delay. 

    Today more temperature loggers were deployed at 25 metre and 5 metre depths on the stunningly diverse and rich seaward slopes of Salomons.  Numerous BRUVS (the camera monitoring systems described previously, of which much more in a later blog) were set on the seaward side of reefs, more cryptic fauna sites were sampled and the last of the various fish transects for this atoll were completed.

    Much of this work is ongoing, the temperature loggers have been in situ (with replacements with new batteries every so often) for six years.  The fish counts, started in 2006, were repeated in 2010 and now again in 2012.  The coral cover measurements have been repeated at various intervals since 1978, one of the longest continuous coral cover monitoring anywhere in the world. 

    Of course there are new projects on every expedition, on this one they are the BRUV and cryptic work and the fish response times (to show how tame or afraid they are compared to other locations in the world).   The evenings are filled with sample sorting for those who collect samples, with data entry and photo transfers.

  • Day 6 - "the most perfect corals I've ever seen"


    Diving on the seaward side of the Salomons atoll today was described  by Heather, one of the scientists here, as emotional.  She said “they were the most perfect corals I’ve ever seen and I wish that more of the world’s reefs looked like this”.

    The corals are thriving and the coral cover is high, probably as high as it has ever been.  And there are painfully few places in the world where that is the case.Salomons Anglaise Pass

    The newest satellite images show that the threat of a damaging warming event for the whole western and central Indian Ocean region has passed for this year.  In Chagos, the main threat to coral reefs is increasing seawater temperature.  This morning we recovered and replaced temperature recorders in the lagoon at Salomons Atoll, as we did in Diego Garcia a couple of days ago.  These have been placed around the archipelago, at other atolls not yet visited as well,  to monitor sea temperature at two hourly intervals.  This is an ongoing programme, and is invaluable to tell us not only what the temperatures are, but to better calibrate the data obtained from the coral cores which are used to give historic seawater and climate information.  It’s always a relief to get to the site and be able to find the recorder, and a relief to find the led light still happily blinking.

    Catherine and Heather’s work involves collecting and examining the cryptofauna which inhabit dead coral heads.  The buckets with the samples awaiting processing live in the ladies toilet on board the ship until processing, which takes until well into each night.  These small organisms are usually overlooked and until now have not been studied in Chagos.  These organisms are the basis of a network of different  food chains and are also important in bioerosion – the process by which corals are turned into sand and continue the cycle through the reef.

  • Day 5 - Salomons Atoll

    Preparing for first diveWe arrived at Salomons Atoll while it was still dark and so waited for first light to enter the lagoon. The captain of the Pacific Marlin, Neil Sandes, has obviously done this many times and the GPS waypoints are well known, but it is still a good precaution to be able to see where you are going.

    We started work immediately, Pete C visiting the islands to do vegetation mapping and bird counts while the rest of us diving. The morning’s dive was on the reef slopes on the east of the atoll, off Ile Jacobin. The water was very clear but a strong current was running which made the work much harder.  Running a 50metre tape transect in a strong current is no easy matter.

    Bob, our expedition medic, has been assigned to work with Nick, our ichthyologist, on fish counts and on an interesting project looking at parrotfish behaviour. In areas where there are a lot of people, parrotfish will swim away from a diver while the diver is still fairly far away. The extent of their wariness has been shown to relate to catchibility – i.e. their vulnerability to fishing. Nick was interested to see how parrotfish who have never seen a diver will react. Bob has to swim towards the parrotfish and as soon as the fish starts to flee, he drops a marker and swims to where the fish was when it swam away, then measure back to the marker using a tape measure. According to Bob, the fish just gave him the middle flipper and dived under a coral head. We await the results of this experiment with interest!

    Nick Fish CountingOn the way to our afternoon dive site, we encountered an abandoned longline. We radioed in to the Pacific Marlin who came and removed it. There are always going to be poaching attempts on an MPA but the Pacific Marlin is constantly patrolling, deterring and arresting.

    After the afternoon dive the water over the reef flat was to shallow to drive the boats over so we walked them over into deeper water. David, the dive supervisor, unfortunately stood on a Diadema urchin, but survived the encounter with only one spine in his foot.

    All work was completed at the end of the day and we thankfully had a cold beer on the bridge watching yet another spectacular sunset.

    References:
    Januchowski-Hartley FA, et al. (2011) Fear of fishers: Human predation explains behavioural changes in coral reef fishes. PLoS ONE 6: e22761.

  • Day 4 - last day around Diego Garcia


    Distances around Diego Garcia atoll are much greater than in the northern atolls as the only exit from the lagoon is the pass at the north.  The other atolls have several passes through which we can get to seaward sites.  This means that it is either a very long boat trip to the work sites on the south of the atoll or we drive down there and dive from the shore, which is trickier than it sounds when you have to get through the breaking waves on the reef crest. 

    Les, the chief engineer, and the Marlin crew, have rigged a winch on the rib for Tom and Jessica to reel in the BRUV equipment.  We are all looking forward to seeing what is down at the depths we haven’t been able to observe before.

    Yesterday’s dive site had high coral cover at 60% average over the reef, so recovery continues to be good and Charles and Anne are delighted at the continuing good health of the DG reefs.

    Pascaline Processing SamplesPascaline, our trainee scientist, is a great help, with, we very much hope, a future in marine biology. With Catherine and Heather she was up till well after midnight helping to process samples.Dive Officer David was roped in too I noticed.

    Pete R, has been a wonder with the logistics, we have never been so well equipped, sorted, labelled and organised.Bob, the expedition doctor, has been working with Nick the ichthyologist (fish guy), recording habitat data along Nick’s transects. He is now aware of the great difference between scientific diving and ‘tourist’ diving. Head down and keep writing on your board while all the local wildlife is lined up behind you making faces!

    Pete C, being based on DG, has plenty of experience of the way things work here and has been marvellous help in obtaining information and equipment.  He will be charting and counting the bird colonies on the islands in the northern atolls, a solitary job with only his radio and clever new  GPS for company.

    Tonight we set sail for Salomons Atoll, always a favourite with every expedition.  The next blog entry will come from there.

  • Day 3 - Manta rays

    Manta RayToday we worked on the reefs on the northeast and north sectors of Diego Garcia, at depths ranging from 25m up to 5m.  Conditions were a little lumpy on the surface but underwater was wonderful as usual.  This photo shows  the manta ray that swam by today, so close it almost swam into one of us,  it was startled when at about a metre away it noticed the diver.  One of the problems with scientific diving is that your head is usually down, carefully observing the half metre quadrat or perhaps a tape in front of you and so you often miss much of the spectacular wildlife that swims by.  A favourite way of winding up colleagues is to ask them if they noticed the shark/dolphin/manta/or some other exotic swimming over their head.  In fact today Heather and Catherine didn’t see this manta as it swam over them, much to their disappointment.

    Huge schools of Jacks, Snappers, Fusiliers and Parrotfish continue to thrive here as they did before. As we dropped ornithologist Pete Carr off on one of the small islands which is packed with birds,  it was nice to see a family of nurse sharks in the shallows.

  • Day 2 - Initial dives

     

    This morning we did a ‘shakedown’ dive to check the dive equipment and see how some of the specialised equipment performed.  In the afternoon we did the first of the ‘work’ dives, recording cryptic fauna, coral cover, recovering temperature data loggers and some pretty complicated stuff to do with the BRUV work! 

    Only Anne, Charles, Pete and Nick have dived in Chagos before and the others, all experienced divers who have worked on reefs all over the world,  were all amazed at the abundance of life on the reef and in the water at Diego Garcia.

    We saw Manta Rays, Eagle Rays, Sharks, Turtles and Dolphins.  There was high coral cover, and more fish than you would believe.  Although there is probably nowhere in the world that could be called truly pristine, this place comes about as close as you can get.

    We got some footage of the Mantas (captured with a little diversion by the BRUV stereo video system) and after processing it tomorrow we will upload it for you to see, along with some other photos.

  • Day 1 - We've arrived!

    Pacific MarlinExpedition members arrived on Diego Garcia last night (13th Feb) and we all boarded the BIOT Patrol Vessel Pacific Marlin.

    Today we had a welcome, and security and safety briefings from the British Representative Richard Marshall  and then from Benito Casquejo , the Chief Officer of the Pacific Marlin.  We are spending the rest of the day unpacking, transferring, and checking out a mountain of equipment.

    Jessica and Tom checked and assembled the baited remote underwater video (BRUV) equipment and the 200kg of pilchards which had been shipped in, in preparation for testing tomorrow morning.  David checked all the dive equipment and Bob unpacked the huge amount of medical equipment and liaised with the medics at the DG hospital for items like morphine which is very difficult to ship in.

    Loading the Pacific MarlinCharles, Catherine, Pete, Pascaline, Pete, Heather, Nick and Anne moved various other scientific and diving equipment.  Heavy work, moving compressors, tanks, boats and engines – especially in the sun.  All equipment was thoroughly checked before we start work for a day or two around Diego Garcia and then sail to the northern atolls where we will continue our various research programmes.

    Cable and Wireless on the island produced some great expedition tshirts for all the scientific and boat crew.  The essential beer order has gone in. 

    After three weeks of high seas and heavy rain in the archipelago, we are lucky that the weather has turned in our favour, with calm seas, clear skies and 34oC.  We are set for the first dives tomorrow.

  • Pete Raines, Expedition Manager

    Well, after two flight cancellations from the UK, I am finally here in Diego Garcia (British Indian Ocean Territory - BIOT). The last time I was here was in 2010 when I served as Expedition Manager on the Chagos 2010 Expedition, and it’s great to be back.

    I arrived on the AMC (Air Movement Command) flight from Singapore and following the usual BIOT Immigration & Customs formalities, was met at arrivals by Major Pete Carr, one of the C2012 team members. Pete, who recently retired from the Royal Marines, now works here on Diego Garcia (DG) as Environmental Manager. Since last Saturday I’ve been lugging three very heavy bags stuffed full of assorted and suspicious-looking expedition equipment half way around the world, and so it was a great relief to be finally able to dump these off in my room at the officer’s quarters before heading for a drink at the Seaman’s Club.

    I met with Commander Richard Marshall, British Representative BIOT, who warmly welcomed me to BIOT and kindly briefed me on expedition matters. I then headed over to meet the Manager of Cable & Wireless, Aaron Richardson, who has generously offered to sponsor the production of C2012 t-shirts. From there, I went to inspect the two-tonnes of expedition equipment which had been shipped into DG via Singapore from the UK and Australia, and was relieved to see that it was all present and correct. The rest of the C2012 expedition team arrive into DG on Monday and so the plan is to move this equipment tomorrow from storage to the Royal Marines base at Moody Brook, where it will be unpacked, inspected, assembled and tested prior to loading on Monday onto the BIOT patrol vessel Pacific Marlin - the ship we will be using for the 14 day expedition. In addition to three new inflatable boats shipped from the UK, the expedition has inherited a couple of rather tired-looking inflatable boats from previous expeditions, and it looks like I will be spending a few days up to my elbows in glue trying to make them seaworthy!

    Everyone here continues to offer tremendous interest in and kindness and support for the expedition, for which I am truly grateful.

Feb 2012 EXPEDITION

Anne SheppardBetween 13th February and 7th March 2012 a scientific research expedition took place in the Chagos archipelago (British Indian Ocean Territory), supported and facilitated by the Foreign and Commonwealth Office and numerous other institutions. Twelve scientists and supporting team members participated in the first full scientific expedition since the no-take marine protected area (MPA) was established in April 2010. Our research plans therefore prioritised the continuation of long-term monitoring programmes as well as establishing the best and most resource-efficient methods to monitor and manage the MPA. We believe our initiatives will assist BIOT in understanding and managing the world’s largest fully no-take MPA, maintaining this extraordinarily rich area of marine and terrestrial biodiversity.

For more information you can download the expedition summary document from our Resources page. You can also download the expedition report to read about what we found.

Aside from guest contributions, the below posts were written and edited by Anne Sheppard, Research Fellow at the University of Warwick and Editor of Chagos News.