Hi Arnaud,

It depends on your research question. You apply what is most applicable, SCUBA for shallow water and remote and manned subs for deep. I would do both. If your career requires you to go deeper, then you need to find another way to continue working in shallow water. Best wishes, Bert

Arnaud,

I hope that the new BBC Earth series "Blue Planet II" will get young marine scientist excited and I hope that many of us that are still doing SCUBA-based research will be able to switch from air and Nitrox SCUBA tanks into re-breathers. It is truly amazing how things look so different down there once you put on a re-breather. Just a thought.

Tomas

Thanks for sharing your feelings on the topic Tomas.

I agree that rebreather is the natural evolution of classical open circuit scuba diving and has started to be democratized over the last few years. However, can't we predict that within few decades robots will be able to perform the same underwater tasks than humans deeper with an extended autonomy? Of course I'm here being devil's advocate since I believe that to truly understand what you are studying underwater you need to observe it regularly with your own eyes. I hope that someone with skills in underwater robotics will share her/his knowledge on the subject...

This is a very good point, I haven't thought of that yet.

It is true that now ROV can be cheaper than a good diving equipment. If you look at OpenRov, they are around 700$ if I remember correctly. Already today they are very powerful regarding studies for reef complexity (3D models etc) and fish surveys on belt transects. These are for the moment studies that are conducted by scientific diver. So yes, for these works, divers might be replaced very quickly in the future, I however think that there are works that can for the moment not be conducted by ROV like underwater sampling in quadrats, experimentations etc. Everything that is not standardized and innovate, is complicated to implement for ROV and will therefore continue to be used by divers, I think.

Interesting trend: I see more and more studies where people prefer free diving over scuba diving because the risks are lower and the logistic is less complicated. I personally prefer using free-diving. And the cost of free-diving is lower than the ROV, so maybe we sill observe a shift from Scuba diving to free diving + ROV?

Hi Arnaud,

It depends on your research question. You apply what is most applicable, SCUBA for shallow water and remote and manned subs for deep. I would do both. If your career requires you to go deeper, then you need to find another way to continue working in shallow water. Best wishes, Bert

I still think nothing can or will beat human observation in situ underwater. While I have no idea on the real end of SCUBA, or its evolution, I truly hope it never does end, and if anything, becomes more important and even safer.

Thank you very much Robin and Bert for your interesting point of view. I agree that the present use of unmanned sampling techniques are complementary to those by scuba diving and in most of the cases can't replace the latter totally. I also agree with James that it is hard to foresee a robot able to provide better observations than human. But what about this if we try to predict future innovations let's say within 30 years? Will these assertions still be true? My knowledge in artificial intelligence could hardly fill a thimble but still, I question myself if robots will be able to provide more accurate observations than human. Almost a philosophical question...

Dear Arnaud

Scubadiving is and will be the best form and tool to take precise data. To day, many others they are appearing out of nowhere, but no one is so effective (at least -30m with normal air) that your eyes. This is an interesting thopic in Underwater Visual Census.

Cheers.

Thanks for sharing your vision Omar. I think that this is a good point to feed the debate.

I must confess that I don't agree with you regarding the new optical and acoustic methods developed recently. I can assure you (as someone working on this topics) that they don't come from out of nowhere given the fact that they are, most of the time, funded by public resources, ordered by environmental agencies and developed by experienced oceanographers. I personal though is that currently both techniques (scuba diving and remote sensing) may be applied and are complementary. But I observe that the balance tips more and more quickly toward remote sensing, logically leading to the disappearance of scientific diving. And then we come back to the primary question: how much time left for scuba diving?

PS I agree with Robin's comments on the use of free-diving for shallow sampling and observations.

Rebreather technology for Scientific diving is the way forward, an ROV or acoustic method cannot beat a thinking diver.

Thanks Joanne for your answer. Totally agree that remote sensing (acoustic, optical, etc.) cannot beat human thinking and that rebreather is the current revolution in the field of scientific diving. For me they are not opposite sides but complementary.

This is for now. But what about within several decades with artificial intelligence and more autonomous unmanned vehicles? I'm not trying to draw a clear line between human observation and remote sensing. I'm just questioning myself on the future of underwater field studies.

An overactive health and safety industry and strained public finances are major factors in the continued use of SCUBA as a tool, at least in the UK. As a result, we will continue to invest in safer, remote methods of accessing these ecosystems, like drop cameras, ROV and AUVs. However, I totally agree with Bert, Tom, James, Omar and Joanne that SCUBA is still an excellent tool that allows people to observe and collect data from shallow marine ecosystems first hand. I truly hope we do not lose it as a means of collecting data (and connecting with the things we are trying to understand).

An interesting discussion, and an area I'm directly involved in.

As previously noted, I also view SCUBA and remote methods as being complementary. For many programs SCUBA methods are the sampling choice in shallower waters (< 20-30 m) whereas methods such as visual surveys with AUV or ROV covering depths beyond this. For temperate marine regions using SCUBA in the shallows is a necessity as algal cover in shallow water makes deployment of other equipment difficult if not impossible.

From a technological standpoint: think that things are evolving rapidly in areas such as AI and auto-recognition. I think for some monitoring programs and certain indicator organisms that this will be the way forward. ROVs and AUVs can cover a lot more ground than SCUBA, however there is a bottleneck currently with human scoring of the imagery. Where this can be automated huge amounts of data can be collected which will make analyses very powerful. However, there will be many cases where humans still need to be involved in the process. Think for example of sponges that can change morphology: It will be very challenging to automate the scoring.

Another factor to consider is the legacy of long term data sets. In some places SCUBA programs have been running for extended periods (I hesitate to say "long-term" as they usually don't measure up to the length of terrestrial programs). The value in these data sets and in continuing these surveys into the future has been highlighted in a number of studies. Many of these programs also utilize citizen science divers, which cuts costs and engages the public. I don't see these programs ending anytime soon.