Marine Biology 411

Photographed something no one can identify? Try Reddit’s marinebiology subreddit.

I posted these images in Reddit’s marinebiology subreddit and asked the question (paraphrased), “what is this?”

Here is the best response so far:

Salps have a complex life cycle, what you are seeing is the aggregate stage, where a chain of blastozooids are connected together. This is the sexual reproduction stage.

The solitary phase, known as an oozoid, and reproduces asexually – creating these long chains of blastozooids. I took a [photo](https://i.imgur.com/BMrTCH6.jpg) of an oozoid, with a chain of blastozoids still inside it. 

Another commenter added:

Those are colonial salps. Each cylinder is an animal 

And, for good measure, here is the Wikipedia (https://en.m.wikipedia.org/wiki/Salp) summary:

A salp (plural salps), salpa (plural salpae or salpas[1]), is a barrel-shaped, planktonic tunicate. It moves by contracting, thus pumping water through its gelatinous body. Salp jet propulsion is one of the most efficient in the animal kingdom.[2] The salp strains the pumped water through its internal feeding filters, feeding on phytoplankton.

For the record, I have not been a fan of Reddit. I won’t go into the reasons why I don’t like the social media platform, but I don’t.

The one exception, so far, has been the marinebiology subreddit. I had a suspicion there was something different about it, and this proves it. The responses were quick and accurate.

So, if you need help identifying a marine organism, I suggest you post photos of it in Reddit’s marinebiology subreddit.

Where Did That Sound Come From?

They say that you can’t tell from which direction an underwater sound came. That’s not entirely true.

Why is it supposedly true? Because sound travels much faster and much farther underwater. 

Above water, sound reaches the ears at slightly different times. The brain uses this difference to determine direction. Underwater, however, sound reaches both ears at the same time. The brain, purportedly, cannot determine direction.

Also, visibility underwater is far less than visibility above water. Many of the sounds we hear underwater are out of visual range even if we happen to be looking in the correct direction.

In my experience, short sounds are mysterious. A dive instructor or dive guide bangs on his/her tank with a metal stick and I look like the Tazmanian Devil, spinning around until I visually detect the source.

The other day, however, I heard a boat. I looked up to my left, and saw it immediately.

So, while the brain cannot detect the source of short sounds, it seems it can figure out direction for prolonged sounds.

Or, maybe I have a superpower. Either way.

Why should you hire a scuba diver?

I was thinking the other day about some of the attributes that every scuba diver must have. This is not necessarily an exhaustive list; I’m just thinking out loud.

1. Follows directions. From the very first lesson, you have to follow your dive instructor’s guidance. And on every dive, you have to listen to your instructor or dive guide. Failure to follow directions can be lethal.

2. Pays attention to details. You dive with a life support system. Once you are open water certified, no one is more responsible than you for your own gear. You need to verify that everything is connected properly and working properly. You need to monitor your depth, air supply, descent/ascent rates, and more. An equipment failure or improper action can be lethal.

3. Doesn’t panic. Panicking underwater can be lethal. Have you noticed a theme? But, it’s true. We train for problems. Therefore, the solution is to stay calm, cool, and collected. Remember your training. You’ve practiced for this scenario. Do what you were taught, and live to dive another day.

4. Is smart. You can earn one certification and then just do fun dives for the rest of your life. But, I don’t think it’s possible to complete specialized training and be stupid. You really have to learn quite a bit about physics, physiology, and more. You have to make plans, do calculations, and prepare for contingencies. 

Keep in mind that humans are not meant to survive underwater. A scuba diver demonstrates an ability to survive insurvivable conditions.

Plus, this article is grossly oversimplified. Too much oxygen can be toxic. Too much nitrogen can make you drunk, sort of. Carbon dioxide buildup can put you to sleep. Permanently. And everything changes depending on what we are breathing, how long we have been breathing it, and at what depth we have been breathing it.

That said, I have now survived an underwater environment 16 times. Officially. It’s 17 if I include my first training dive, which does not count as a logged dive.

However, I know instructors who have survived hundreds of dives. I know someone who has logged about 2,000 dives. I even know someone who has logged a mindboggling 13,000 dives!

My point is, it’s very easy to die underwater. Simply breathing in water is enough to do it. So the attributes it takes to survive under such alien conditions is something that I think employers should consider taking a look at.

1st Dive at Gilutongan Island

Look carefully at this photo. See the color change? That’s the top of the wall. The blue-colored water is about 60 meters deeper.

Dive 16 was a wild ride. Like dive 15, I was the most experienced diver after the dive guide. One diver had a brand new open water license and only 4 logged dives. 

The newest diver actually had some difficulty at the start of the dive and returned to the boat. He apologized to everyone when we returned, but I told him it was unnecessary. It’s much better to turn back than to give us a serious issue to deal with underwater. He did the right thing.

Anyway, we went to Gilutongan Island, part of the Olango Island Group in Cebu, Philippines. It was my first visit to the Gilutongan Marine Sanctuary.

The group was originally 6 divers, but became 5 divers when the 1 diver turned back. Shortly after we started, I saw something very disturbing.

I thought I saw a distressed diver scenario, so I went for a closer look. Some tour operators, it seems, bring down tourists in scuba gear minus the fins, and let them stand on corals with their booties. They were hunched over a sea anemone, disturbing the resident marine life. They were also feeding the fish and doing everything any real diver should know not to do.

So I stopped them. The guides physically elevated their guests. Realistically, they probably resumed as soon as I was out of visual range. I’m still angry about it.

I raised the issue later at my dive center and, unfortunately, the practice has been going on for years. The marine sanctuary allows it so that the tourist money keeps coming in. I suspect this is why my dive center does not normally send divers or island hoppers (other on-land issues, as well) there. This was an exception, because one of the guests really wanted to go there for some reason. I’m happy that my dive center generally avoids this place.

Remarkably, especially considering the horrific tourism practices, the dive site is in great condition. Somehow I didn’t get all the photos I took (must’ve been a technical issue transferring files) but the wall looks healthy. Sadly, it’s not worth supporting a marine sanctuary that allows tourists to stand on corals. In the future, if others want to go, I’ll talk about how amazing some of the other dive sites are and try to subtly change their minds.

Some of the photos I am missing include a school of fish playing “follow the leader.” I have never seen an entire school of fish swim single-file before. It went on for quite a while, so I really wish I could show it.

The dive lasted 45 minutes and my maximum depth was 20 meters.

We swam into a strange current. It wasn’t pushing us backward, but it took more effort than normal to go forward. It was easier to hover in place, actually.

When we surfaced, I realized how little distance we covered. Using landmarks on the island, we really hadn’t moved much. It felt like we saw a lot, however, and that’s the important thing.

Unfortunately, the whole dive was marred by the group of tourists that was standing on corals. Which is the bigger dilemma: boycotting the dive site or returning in order to play superhero to the corals?

On a positive note, we only found 5 small pieces of debris weighing a total of about .1 kg. I have already submitted the survey to Project Aware’s Dive Against Debris.

Underwater Vomiting (Not Me)

Dive 15 was a historic first, in that I wasn’t the most junior diver. I thought it would take a long time before that happened!

My group was just me, a dive guide, and one other diver. I don’t recall his dive count, but I remember it was less than mine.

We went to Talima, off Olango Island in Cebu, Philippies. My dive buddy normally dives further north, so this was his first time diving coral reefs.

It had been a while since his last dive, so our dive guide kept the dive short and shallow. We spent 38 minutes underwater and only went to the top of the wall, which is about 13 meters down.

Unfortunately, my dive buddy got sick. I didn’t realize it at the time, but he vomited twice while still underwater. I saw him remove and replace his regulator, but since I didn’t see any evidence of vomit I didn’t make the connection until we were back on the boat.

He wasn’t up to a second dive, but I saw him after my second dive and he looked much better and said he felt much better. We’re not quite sure what happened, but he ate breakfast in a foreign land, so who knows what may have disagreed with him.

Our dive guide also thought buoyancy may have been a factor. The boat ride to the dive site was very rocky, plus his buoyancy resulted in numerous depth changes. So maybe all those pressure changes at 5-13 meters played a role.

I have not had to test this out myself, but I have read in quite a few places that regulators are designed to accomodate vomiting. I’m not sure if my dive buddy vomited with the regulator out or just removed it to clear it, but hopefully I will never have to test that theory myself.

I’ll end with noting that for me, not knowing how ill my dive buddy felt, this was a very easy, relaxed dive. I took quite a few photos, fought with the camera a little bit, but found the overall dive very enjoyable. 

Once on the boat, I switched to trying to comfort my dive buddy. It probably helps that I can empathize, having had an awful dive myself. And, he was able to recover within a few hours. Hopefully he’ll get past this and continue scuba diving.

One final note: the dive site was very clean. I only found one piece of debris, which I have reported to Project Aware’s Dive Against Debris.

Upside-Down Photography

Scuba diving upside-down is a newfound thrill, ever since participating in a coral reef restoration project. We had school-age children snorkeling above us, watching what we were doing. A few times, I rolled onto my back and snapped a few photos of them on the surface.

Since then, I have engaged in all kinds of underwater acrobatics. I roll onto my side to photograph my dive buddies. Also, I roll onto my back to photograph divers and other interesting things above me. For example, when drifting along a wall, divers usually end up at different depths and schools of fish swim directly above.

I don’t think this affects my buoyancy or air consumption much. I do the same thing I normally do, except 180° rotated. I sometimes roll over and then tilt upward to photograph divers behind me, and that is definitely bad trim, but that is very brief and too much fun to stop.

For the record, I stay on my back and sides for very short periods. I want to make sure I don’t collide with anything or anyone. I only take a photo or two or three, and then resume proper trim. Or, if I am going to observe something for a while, such as a school of fish, I’m more likely to go vertical for a while, which is what other divers seem to do.

Anyway, I’m far less concerned about the length of my dives, in regards to air consumption, and far more interested in having awesome, fun, yet-still-safe dives.

2 More Project Aware Surveys

Two different groups on 2 different dive sites only found 6 total pieces of debris weighing about .1 kg.

The first site was Talima, off Olango Island in Cebu province, Philippines. I only found a single plastic bottle. That’s much better than last week’s find, which included a diaper.

The 2nd dive was at Gilutongan Marine Sanctuary, and this was my first time there. We found a little more debris, but still very little. That’s surprising, actually, considering the awful tourism practices over there. I’m guessing that someone does a lot of clean up dives over there to keep the tourists coming. 

2 More Project Aware Surveys

Over the course of 2 dives, my groups retrieved from the ocean 15 pieces of debris weighing .7 kg.

The most unusual, and most disgusting, find was a diaper. I briefly hesitated to pick it up, but I reminded myself that it didn’t belong there. After the dive, my dive buddy said he couldn’t believe it when he saw me actually pick it up. 

The diaper was on the wall at Talima, off Olango Island, Philippines, at a depth of about 25 meters. No other debris was found. It is as if someone changed a diaper on a boat and then tossed it into the ocean. But, who changes a diaper on a boat? And, why is a baby even on a boat? Well, I don’t have the answers, but I do have the diaper. 

Overall, considering these 2 dives included 7 divers for 40 minutes and then 5 divers for 45 minutes, I consider myself fortunate that my nearby dive spots are relatively clean considering how many environmental disasters I see shared on social media.

Dive 14

This exciting fun dive introduced another new dive buddy. Our total group was me, my dive buddy, a married couple, and our dive guide.

We went to Kontiki, off Mactan Island in Cebu, Philippines. It was my first time at this dive site. We didn’t see the ginormous excavator clamshell bucket artificial reef, but the dive was still amazing.

This was my first impression:

We saw quite a few interesting things like this down there. Our best guess is that there is a fairly large coral reef restoration project underway.

I took the previous photo on descent, and this next one at our safety stop:

Also, soon after descent, we reached the top of the wall. Visibility was poor enough that I could finally capture an “end of the world” shot. This is surreal, because you can’t see anything but abyss when you look down or when you look away from the wall.

Around the start of our safety stop, before we realized these large objects are probably for a coral reef restoration project, I saw what seems to be an overturned table. I went closer to take a photo and discovered another table next to it. I motioned my group over so everyone could see the corals that someone is growing there.

And that’s when I took the featured photo for this blog article. I took quite a few photos, actually, of the wall and other things, and I will slowly be sharing those photos across my social media accounts.

This dive lasted 45 minutes and my maximum depth was 18 meters. My group picked up debris that I will be reporting to Project Aware.

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