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Coral Triangle

Expedition to Halmahera: Week One

Follow Nature Conservancy scientists Alison Green and Rod Salm as they blog about their expedition to an unexplored heart of coral biodiversity in Southeast Asia! 

Saturday, April 12th: A Great Team Assembles for the Trip

We're close to starting the expedition: After a day in Bali, we flew to Manado in the northeastern part of the Indonesian province of Sulawesi. This was where the whole expedition team finally gathered after travelling from all corners of the globe — Australia, Hawaii, Virginia, Paris, and Jakarta as well as Halmahera and Raja Ampat Islands.

It's great to have the whole team assembled at last. What a fantastic mix: seven world-renowned coral reef experts and nine excellent local scientists. It will be a great trip! (Alison Green) 

Sunday, April 13th: Four Weeks Aboard This Boat

This morning we boarded the Seven Seas, our survey vessel and home for the next four weeks. The Seven Seas is an Indonesian-style vessel with teak floors, designed as a live-board dive boat for remote areas in Indonesia. So it is uniquely suited to our trip.

After ferrying the survey team and our mountain of equipment to the vessel, we departed for Halmahera — a 21-hour sail away. We were lucky with the weather and were able to sail at about 15 kilometers per hour, which is quite comfortable on a vessel of this size.

Sailing from Sulawesi was absolutely magic — the weather was perfect, the scenery beautiful and the survey team relaxing as the crew set sail. Everyone is very excited because we will soon arrive in Halmahera. What will we find? The global center of biodiversity — or something else? (Alison Green) 

Monday, April 14th: Baby Corals in the Ring of Fire

We arrived in Halmahera this morning. Finally! After months of planning and four days of travel from home, we are finally here.

I woke up early and went up on deck to see Halmahera emerge over the horizon. It's a large green island with huge volcanoes emerging from the sea — a stark reminder that we are in the seismic "ring-of-fire," where tectonic plates collide to form hulking volcanoes, earthquakes and sometimes tsunamis. We anchored in Tuluk Bayo (Bayo Bay) on the mainland, where we all raced up on deck, dug out our dive gear and went for our first dives on Halmahera.

I am working with the coral reef monitoring team, which is composed of local scientists, and it is always such a treat to work with them. We set off to do our first survey of corals and reef fishes in Halmahera.

Initially we were dismayed at what we saw — these reefs had suffered a major impact about 10 years ago, so there was a lot of dead coral around. Dynamite fishing is also common in the area.

But then we looked more closely and saw lots of baby corals, and realized that recovery was underway. Phew, what a relief. Despite the damage to the reefs, diversity was high — and our coral and fish experts are excited by the diversity they were already seeing. Imagine what we'll find when we find a healthy reef!

I also saw a huge green turtle, which was a nice surprise. We did two dives in this area and then steamed north overnight. (Alison Green) 

Tuesday, April 15th: Breathtaking Dives!

We didn't have to wait long to wait for two excellent dives!

Our first dive this morning was on Pulau Adui (Adui Island). When we first got in the water, I thought, oh no, this isn't very good either.

But then Andreas — the Conservancy's fish-monitoring expert from Raja Ampat — and I started to swim and count the fish, and we suddenly came upon a breathtaking site, a point in the reef where there were a lot of big fish such as napoleon wrasse, big snappers, emperors and sweetlip, and lots of big colourful parrotfish.

These species are all particularly vulnerable to overfishing, and I am always so excited to see them — you see them so rarely these days. I was particularly pleased to see napoleon wrasse: One is a good sign, and we saw eight! Fish diversity was also high here, with lots of colour and diversity of shapes and size, and lots of weird things like frogfish and pipefish.

Our second dive at Pulau Sidanga was also lovely — healthy vibrant corals and lots of fish. We also saw two endangered hawksbill turtles. We swam right up to one of them and it didn't swim away. So trusting!

Since this was an exposed outer reef, there were big schools of planktivores feeding on the plankton — lots of colour and movment, with waves of fishes moving up and down the reef, particularly damselfishes, unicornfishes, surgeonfishes, and fusiliers.

I was pleased to see lots of healthy Acropora (branching coral) at this site. This coral is particularly vulnerable to coral bleaching, and has been killed in many areas of the world. So it was good to see it healthy and thriving here in Halmahera. (Alison Green) 

Tuesday, April 15th: The MEA Starts in Earnest

We tucked in under the lee of the island of Tanjung Bobo, happy for a respite from rolling in the swells, and the MEA started in earnest.

We have three teams, and they're all busy. The socioeconomic/resource-use team headed off to two villages that occupied them for the day. The monitoring team set off to do their counts of benthic cover and fish indicators of resilience. The biodiversity team dived straight into counts of fish and coral species and recording reef resilience. Energy levels were high and most managed 4-5 hours underwater.

The divers were greeted by thickets of the fine-branching and most elegant staghorn coral, Acropora halmaherae, first found and described here in Halmahera. We've also learned that this is the nesting season for the olive Ridley turtle and that one came ashore two nights ago. Three turtles were seen underwater and divers now have been briefed on turtle identification and encouraged to report the species seen.

Something impacted the reefs here about 10 years ago. It could have been linked to the 1998 worldwide bleaching event or an outbreak of the crown-of-thorns starfish, a voracious coral predator.

However, every impact has a trade-off, and the rubble banks are now home to numbers of exquisitely colored nudibranchs (shell-less snails with exposed gills). These beautiful creatures, called sea slugs by the irreverent, find good food and shelter on these recovering areas of dead coral.

We've started our coral and fish-diversity lists—and we're already into the low 200's for both fishes and corals. (Rod Salm) 

Wednesday, April 16th: Coral Older than Methuselah!

What a morning — we have dropped into coral heaven, a veritable garden of colorful, healthy hard corals almost completely blanketing a rocky shelf. Our coral recorders estimate 250 coral species at this site—about equivalent to the sum of all sites, and with good color and negligible signs of stress from predators or disease.

This morning we went for a dive just north of Tuluk Loloda (Loloda Bay), and landed right on top of an enormous coral colony — a gigantic colony of the massive coral Pavona clavus (16-17m in diameter), which our coral experts tell us is older than Methuselah, who was reputed to have lived for 969 years!

There were some lovely areas of high coral cover, but no big fish. Too much fishing, I suspect. But despite the lack of big fish, the site was very diverse — about 250 species, according to our fish expert Gerry Allen.

On the way back from our dive site, we stopped off for a freshwater rinse in a spring-fed waterfall that plunges 30 meters down into the ocean, forming a deep pool behind the reef. We managed to get our boat in there and under the waterfall, and everyone had a freshwater shower — it was like being under one of those special massage shower heads. The corals looked so good, we decided to go back this afternoon for a dive.

And when we did, the site turned out to be incredible! I ran into one of our coral experts, Lyndon Devantier and he said the coral diversity here was "outrageous"! I can't wait to hear the total number of species they recorded.

The fish were also very diverse, because the waterfall added a new set of conditions we haven't seen anywhere else. There were a lot of weird and wonderful species in there — some that might turn out to be unique to that area. There were also lots of big fish — snappers, sweetlips and (my favorite) a HUGE humphead parrotfish, about 1 meter long.

The humphead parrotfish consumes more than 5 tons of live and dead coral each year and plays a key role in bioerosion on coral reefs. They grind the carbonate up into sand, which they excrete around the reef - sometimes you wonder what is falling on you and it is sand from the parrotfish. It is a great honour to be pooped on by one of these species!

But these fish are very vulnerable to overfishing, particularly spearfishing. So I'm always pleased to see them.

As I swam in over the reef to the waterfall pool. the top layer (about 2 feet thick) was freshwater and cloudy, while the water underneath that was salty and crystal clear. Very strange. Everytime I lost my buddy in the top layer, all I had to do was sink down to the clear layer below to find him again.

When we swam into the pool below the waterfall, it was like swimming in a primordial soup. The bottom was black sand, and there were corals and coral reef fish in the pool below the waterfall! That was a big surprise — we expected that the freshwater would have killed all the coral.

Ballpark estimates of species are 500 for fishes and 400 for corals. This is remarkable after only 3 days of recording. The scientists are working hard to keep up with the high yield of new records at every site; and are excited to find new records for the area and extend the known ranges of several species. (Alison Green) 

Thursday, April 17th: Paradise for Fish Geeks

We went on the most amazing dive today — a wall dive around the outside of some offshore rocks, with a very steep droppoff into the deep blue abyss and a lot of exposure to ocean swells and currents. Not for the faint hearted!

We swam around the rock island looking for big fish, and we weren't disappointed. The water was crystal-clear (100 feet or more of visability), and there were LOTS of big fish — two sharks, 15 humphead parrotfish, a napoleon wrasse, huge schools of planktivores (triggerfishes, surgeonfishes and unicornfishes) and the biggest dogtooth tuna I have ever seen. It was exhilarating.

It was the sort of dive where one needs to be careful — it would have been easy to get so excited about what we were seeing that we would forget our time and depth, or get washed away from the rock and out to sea. The humphead parrotfish were incredible: huge fish cruising past like Sherman tanks, swivelling their eyes to keep us in sight, and stopping occasionally to crunch on the reef. (Alison Green) 

Thursday, April 17th : The Species Counts Keep Climbing

We covered the North Loloda Islands today, finding very different environments that have kept our species counts climbing for both corals and fishes.

One site had absolutely transparent water and schools of fishes, including some large pelagic fishes — including an enormous dogtooth tuna that still has Alison Green and Andreas Muljadi talking. Large humphead parrotfish and coral trout pleased the fish team.

We also covered more sheltered habitat that showed typical whorls of leafy corals and large patches of branching forms, too. The corals were extensively damaged, but the beautiful intact patches were pleasing to see — or “mind-blowing,” as our colleague Emre Turak’s simple observation.

He and Lyndon DeVantier are getting 200+ coral species at each site, which is more than anywhere else these world experts have surveyed. There was absolutely runaway recruitment of new corals onto the damaged patches, which thrilled and kept me busy as the reef-resilience recorder. This development is a strong indicator of the ability of the reef to bounce back if allowed to do so.

Gerry Allen, who is covering fish diversity, is recording over 200 species daily and now has nearly 600 after only four days on the expedition — an unprecedented number in his experience. (Rod Salm)

« Expedition HalmaheraFollow along on the rest of the expedition: Week Two »


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