Plenty of dive magazines and websites will direct you to the last remaining places in the ocean that still seem healthy and beautiful. But, if you’d like a realistic/horribly depressing idea of what our underwater world looks like when we don’t care for it, here are some of my favorites. You can also feel fairly certain you won’t see sharks at any of these places—those tend to be fished out quickly.
1. Near London, Kiritimati Atoll, central Pacific.
Also known as the “Ulva Dance Party” site. Ulva, along with some other types of fleshy macroalgae (or seaweed), is used as an indicator for nutrient pollution. Here, “nutrient” refers to inorganic compounds like nitrate and phosphate—what you might use to fertilize your house plants. Where there are excess nutrients, whether from sewage or golf course runoff or perhaps changes in the way nutrients cycle through the food chain due to fishing, these kinds of algae flourish. Also helpful in the macroalgae-domination-transition is a relatively small herbivorous (plant-eating) fish population, due to fishing them out, too.
This site was also particularly nice when we were there, because of strong surge. In order to get down underneath the ulva and identify the few remaining live corals and the relict dead coral (we’re interested in whether these two groups are different), we had to either fight the current to stay in place for a moment, or try to go with the flow and identify on-the-fly as we rocketed back and forth across the transect. A combo of the two seemed to work best—watch the video to get a feel for what you are missing.
[I can't guarantee this won't make you seasick!]
Kiritimati does present some amazing coral-ogling opportunities away from the larger towns, however. So be sure to dive elsewhere to get an idea of how things perhaps used to look.
2. Chachahuate, Cayos Cochinos Honduras.
Unfortunately this site is probably no longer as gross as it once was—the original “long drops” at the end of short piers on this tiny, rather densely populated sand island have now been replaced by composting toilets. So diving off of this caye may not get you an instant, roaring ear infection anymore, and the coral may be recovering. When I last dove here in 2006 – good lord, has it been that long?! – many corals were being smothered by sewage-fueled macroalgae and mats of cyanobacteria were marching over the substrate. But, there was also a cool wrecked airplane, and that kind of made swimming in poop-water Ok.
|Part of the wrecked airplane, with hard and soft corals|
|The orange stuff is a thick mat of cyanobacteria|
3. Western Teraina, central Pacific.
Kind of like the degraded part of Kiritimati, but replace the ulva with cyanobacteria and sea urchins. And intensify the surge. Note that urchins like to eat into dead coral; thus the effort of trying not to get stabbed while grabbing onto a section of dead reef to stabilize oneself long enough to attempt to identify said severely bio-eroded coral puts this experience in my top ten most exhausting endeavors. If you’d like to feel as though you’ve landed on a completely hostile aquatic planet, this is the dive location for you.
|There are at least 8 urchins in this photo|
|Our surveys include identifying live and dead corals under a transect tape laid over (in this case, tied to) the reef|
4. South Molle, Whitsunday Islands, Australia.
For one thing, you get to wear a neon “stinger suit” (see below) to prevent death by poisonous jellyfish. Also, there is very little to see because the water tends to be murky, so you may not notice that the bottom is mostly blanketed by, yet again, our friend macroalgae. My photos from our kayak-camping-snorkel adventure (seriously recommended, what fun!) have been lost, so you’ll just have to imagine this one. While the outer Great Barrier Reef far from land is still quite spectacular in many of the less-trampled locations, sites close to land tend to be less coral-reefy and more algae-field-like.
|So stylish! I stole this photo from somewhere online and then forgot where. Sorry, dudes|
5. Bikenibeu, South Tarawa, central Pacific.
If you ask at the hospital, you can probably be directed to get as close to the main sewage outlet as possible. The best thing to do is free-dive at this site, preferably without fully clearing your ears so that you perforate an ear drum—all the better to get a most impressive ear infection that requires five types of antibiotics to conquer. Aside from the thrill of bobbing at the surface, being tossed around by large, fierce ocean swells offshore of an island in the middle of the Pacific, you can also see an interesting example of coral monoculture. Though there is fairly high coral cover (and not as much macroalgae as some of these other sites), it is mostly all one species—kind of like an underwater cornfield. Since coral reefs are usually considered the “rainforests of the sea,” with extraordinary diversity, you are correct in thinking that an underwater cornfield probably doesn’t function the same way as a more intact reef.
|Lots of Porites rus - and not much else.|
Sadly, this is only a short sampling of places humans have very obviously degraded the coastal ocean. These effects are not restricted to coral reefs, either (it just so happens I know most about them). With conscious effort, the trajectory towards degradation can perhaps be reversed…but first it has to be recognized. Wherever you next stick your head under the water, give a good think about whether what you are looking at is healthy. Do you think it looks the way it has always looked? Or can you see dead ghosts – a lack of fish, large dead empty shells, old corals covered in algae? It’s hard to know what was there before, but that’s where my kind of work comes in—to use a form of environmental forensics to figure out how things have changed, and why.