Ambon and Halmahera fieldwork: Mini-blog 3 – Surveying Ambon’s reefs

In the previous fieldwork blog I wrote that we were about to leave on the boat to survey coral reefs around Ambon. So let me walk you through how our first week went.

Leaving Ambon took a bit more effort than expected, getting the necessary pre-departure paperwork signed off took 6 hours instead of 10 minutes, but we finally managed to leave late afternoon. We left under a rather gloomy sky, with grey clouds and scattered rain showers seeing us out of the bay instead of the bright sunshine we hoped for. But with an overnight boat trip ahead of us to get to the first sites, we could maybe wake up to blue skies.

That, unfortunately, was not meant to be…

Leaving Ambon

Gloomy Ambon skies

When I mention “dive expedition in Indonesia”, most people tend not to imagine grey skies and unrelenting rain, but the lush tropics wouldn’t be quite as lush without lots and lots of rain! Throughout the week we had plenty of rain, sometimes so much we had to postpone dives because of the limited visibility at the surface: the boat driver needs to be able to see the divers at the surface to pick them up when surveys are done.

 

But we had come to Ambon to study coral reefs, so (mostly) undeterred by the rain, we hopped in and started our work! The first thing we noticed was a conspicuous lack of…coral. We started surveys in an area with a lot of human fishing activity, and it showed, big time. We did not hear any blasts while diving, but there was a lot of evidence of dynamite fishing. Entire reefs were reduced to rubble, some places even had large bomb craters, something I had never seen before. I dread to think about the size of the bomb and the immediate impacts of its blast. A lot of explosive power is required to leave a 40cm deep, 1.5m wide crater underwater!

It wasn’t all bad news though, some places were showing slow signs of recovery, which could mean they hadn’t been bombed for a while. There were still some large fish left, nowhere near as many as there should be, but I did spot a few large groupers and emperors, and even a few adult blacktip reef sharks. We saw encrusting algae and small coral slowly starting to take hold in some places, although they were still a long way from becoming a real coral reef again. I would estimate it could easily take another 50-100 years for these sites to become a fully functional reef, even if they were left in peace and there were no other impacts.

 

After a couple of days of rain and survey dives that made our hearts ache, the team’s morale (or at least mine) had seen better days. Luckily, two things happened: we moved on to sites that had less fishing pressure and the sun started shining!

This part of the trip brought home just how rich coral reefs can be if you just use them in a less destructive way. Sites with very high and diverse coral cover, big schools of fish, lots of invertebrates, funky critters, everything you could want in a dive. This time our only regret was that the tight schedule didn’t give us time to explore each site more thoroughly. Between trying to count and identify large schools of mixed fish species, processing eDNA samples and entering data, little time was left to do anything else than eat and prepare for the next dive. Not that I’m complaining though, being able to work on reefs like this is a privilege that never gets old.

We were also privileged to see some of Ambon’s funky critters. During quite a few dives we came across ghostpipefish (Solenostomus paradoxus and S. cyanopterus), a rare sight on standard coral reef surveys. Our invertebrate expert had his work cut out counting a variety of nudibranchs, shrimp, cowries, and anything in between. Even the algae crew got more fish than they bargained for when a giant frogfish (Antennarius commersoni) decided to swim by and say hello.

 

Despite some adverse weather and a slow start, we finished surveys within the planned time and arrived back in Ambon Bay two days ago. Our two days on land were put to good use, catching up on data entry and admin, meetings, and even catching a movie last night (Joker, pretty good actually). Tomorrow we leave at first light for a longer trip. We are headed to Halmahera, an area where precious little information exists on the health of coral reefs. If all goes according to plan, I should be able to write an update from Ternate in about 6 days!

Advertisements

Ambon and Halmahera fieldwork: Mini-blog 2 – Logistics

I have made my way to Ambon since the last blog, where I have been preparing the last logistics with my local colleagues from Pattimura University before the actual fieldwork begins. In the last 3 days, the other team members have also started arriving, with the final team member (and master fish counter) landing tomorrow morning. The main things that had to happen before our boat leaves port (besides recovering from jetlag), was organising a detailed plan, training new team members, and preparing all the gear. 

IMG_7485

Cloudy Ambon days

One of the things we will be doing, is collecting environmental DNA (eDNA) to study biodiversity on coral reefs. If you want to know more about eDNA, I have written more about it here or here. In short: eDNA are tiny fragments of DNA in the water column that come from poop, mucus, etc. By filtering and analysing a scoop of water, we can tell what lives in the area we took water from. Because eDNA is such a new method, most people have not used it before. So in a great mutual benefit arrangement, our Pattimura University colleagues took us (my colleague Dom and me) out for a dive and in return we showed them how to collect water 😉

We obviously did more than just collecting seawater, we also went back to the lab to teach them the protocols on how to filter samples while avoiding contamination. Since eDNA analysis is so good at picking up the tiniest fragments of DNA, a careless brush of a fingertip can render the entire sample useless. We are collecting data from a boat instead of a high-tech lab, so being aware of how things can go wrong is absolutely crucial to get reliable data.

Tomorrow morning we set sail (start engine?) for 10 days of research around Ambon. So today we had make sure all the equipment got to the boat, for us to leave at first light in the morning. Between dive gear (including compressors, tanks, etc), survey tools, eDNA equipment, and other random practical bits and pieces, it took multiple returns trips with the pickup to get everything to the boat. Science is of course hungry work and feeding 16 people takes a lot of grocery shopping, which was luckily taken care of by our local team. Gino (our Ambon trip leader) has assured me we have an excellent chef on board, so be aware that there is a decent chance that the rest of these fieldwork blogs will mostly be about tasty Indonesian food!

As we will be on a boat for quite a while in the next weeks, I am not sure yet if I will be able to post blogs until we are back on the mainland. If I can snatch up some 4G signal along the way, you’ll be able to read an update on the fieldwork in a couple of days. Otherwise, the next blog will be online around the 11th of October.

IMG_7494

Sunny Ambon days

Psychedelic Frogfish!!!

There was some VERY exciting news last weekend, the elusive Psychedelic Frogfish (Histiophryne psychedelica) has been spotted again in Ambon! This very rare and very trippy frogfish has only been described in 2009 and has hardly been seen again since. Practically nothing is known about them, except for the fact that they are amazing! Here is a video (property of Dive into Ambon) to prove it:

The psychedelic frogfish has only ever been seen alive in Ambon and they don’t seem to get much bigger than 10cm. Their exceptional colouration provides excellent camouflage and is thought to mimic coral species like Symphyllia sinuosa, Pectinia lactuca and other corals with similar morphology.

Symphillia and Pectinia

S. sinuosa (A) and P. lactuca (E). Photos: D. J. Hall from Pietsch et al. 2009

As a species of the genus Histiophryne, Psychedelic frogfish are “egg-brooders”, meaning they keep their eggs attached to their body to protect them from predators. It is even believed that they might use their eggs as bait to lure fish in that don’t recognise the eggs are attached to a predator larger than themselves! This is what it looks like:

Psychedelic frogfish_eggs

Psychedelic frogfish with eggs. Photo: Francesca Diaco from Dive Photo Guide

Who could not get very enthusiastic about a fish this bizarre and beautiful? Just too bad I don’t have time to go to Ambon myself any time soon 😉