5 Things to Think About When Doing Scientific Diving
"Scientific diving is much more complicated than one might think. When you take a human being underwater, we become twice as stupid." - Dive guru, Researcher, Stefan Follows.
Every diver has the capacity to operate underwater as a marine researcher. In my opinion that is the future of marine science - Citizens in the water around the globe collecting data using uniform methodologies. However, without the proper training and skills, we can end up doing more harm than good. So without further ado, 5 things to consider when undergoing scientific diving:
This is arguably the most important aspect of not just scientific diving, but any form of recreational diving. Buoyancy is the ability to float in water. Something can be positively buoyant, meaning it floats at the surface. Negative buoyancy is when something sinks to the bottom. Neutral buoyancy is where we aren't floating and we aren't sinking. Instead, we are positioned at a consistent depth using our buoyancy compensator (diving vest), and our breath.
The buoyancy compensator is meant to only be used a few times throughout the dive. When we reach our diving depth, we adjust ourselves into neutral buoyancy using our Buoyancy compensator, and then use our breath to control our position for the rest of our dive. You can think of our lungs like balloons. If you were to fill up a balloon with air at 20 meters of depth and tie it off, it would float up to the surface. The same applies to our lungs. When you breathe in, your lungs fill up with air and start to take you up. When you breathe out, your lungs deflate, and you start to sink. Using this breath control, we can hover close to the bottom without contact, which is critical when collecting data.
Neutral buoyancy is used on every survey dive, and every recreational dive I do. When we collect coral cover data, we are swimming along a permanent transect taking photos 1 meter above the substrate, and identifying parts of the substrate <1cm in diameter. When doing reef cleanups, we have to use scissors to cut off nets and fishing line from the substrate. Poor neutral buoyancy would lead to ripping of coral tissue and damage to the substrate. With our fish surveys, many fish tend to be benthic, hiding down in the substrate. Without good neutral buoyancy, we would miss keystone species.
This seems like a joke, but it is the furthest thing from it. Fin techniques are the difference between a good diver and a great diver. There are two classical ways to kick underwater. the flutter kick and the frog kick. The flutter kick is where you have your legs out straight and you are kicking. Look at any great diver, and you will see that they hardly EVER flutter kick. Using the frog kick, we have much more control over our body positioning. If we want to turn left or right, we simply keep one fin still, while the other one frog kicks. This turns us on a dime, rather than swinging our entire body around using the flutter kicks. For advanced divers, the reverse frog kick is arguably one of the most useful skills to learn. Using a combination of all of these techniques we can essentially be a drone underwater, turning and reversing on a dime.
For all of our surveys, it is important that we keep our eyes forward. Fish tend to swim. If we are constantly swinging our bodies around, we risk either missing important organisms, or counting the same ones twice. For our coral cover surveys, we are looking straight down at the substrate. If we accidentally glide over our survey point, it takes 5 times as long to turn around using flutter kicks. Instead, we reverse frog kick once, collect the data, then continue forward.
If you've ever gone diving, you will immediately see that you're breathing is not the same as your buddy. You always hope that you are the buddy that is better with air consumption. Nobody likes being the reason the dive comes to an end. When we are conducting research dives, it is often imperative that we stay underwater for 60+ minutes. Therefore, bad air consumption can lead to a job not getting done.
When we first learn how to dive, we are taught to breath deep and continuously. This often leads to people gulping air. What often gets left out is LONG and CALM deep continuous breathing. When I breathe from my regulator, my inhale usually lasts 3-4 seconds, whereas my exhale lasts 10-15 seconds. I typically am using that exhale to control my buoyancy. This leads to better buoyancy as well as longer dives. Therefore, we can collect more data, remove more debris, and restore more coral.
Scientific Diving Plan
Due to the intricacies and nuances discussed above, a different style of dive plan needs to be employed when conducting research dives. We are staying down for longer, which means we have a higher risk of decompression sickness or running out of air. Deeper dives also face the risk of gas narcosis. Therefore, it is critical that we identify closest medical facilities, recompression chambers, and emergency contacts.
With recreational diving, we always dive with our buddy. However with a scientific dive, we have additional backups. We always have our dive buddy, but we also have a time limit set at the dive shop prior to departure as well as a support personnel on the boat or at shore. Before conducting any form of scientific diving, check in with local municipalities, research institutions, and NGO's to see if you can have a look at their scientific diving manual.
This is always the part that people LOVE to talk about. When you begin your diving career, you start out with absolutely nothing. You get your first mask and fins, and then you are hooked, and for a good reason. There is plenty of different styles of dive gear, all with it's own designated purpose. After diving on dozens of different setups throughout my diving career, I have a clear cut favorite when it comes to a BC and regulator combo. The WTX-D30 BC by apex is the most well rounded BC for research purposes. The air bladder is a back inflate which automatically puts you in the trim position, which is the position you should ALWAYS be in when surveying. The stainless steel backplate allows most advanced divers to dive without bringing additional weight.
The best regulators also come from Apeks. the Apeks ATX40 and AT40 are the best bang for your buck regulator on the market. the only difference is that the ATX40 can tolerate cold water dives. If serviced on time, these regulators will last you a lifetime. If you are looking to take a step into the world of luxury, then the XTX50 is perfect. Full adjustability in breath restriction and purge.
When it comes to masks, you just need to find one that fits your face. Everybody has different sized faces, and masks fit everyone different. However, when it comes to fins, there is definitely a clear cut favorite. the Apeks RK3. Are you seeing a pattern here? These fins are designed to mimic a frog's foot. Therefore your frog kicks will be spot on every time.
There is definitely a lot more to think about when it comes to scientific diving, however, these are the basics that everyone should know. Follow these 5 steps and you will notice an immediate improvement in your diving.