Know Your Neighbors: A Tale of Two Oceans

October-November 2006

This is an article from WaveLength Magazine, available in print in North America and globally on the web.
To download a pdf copy of the magazine click here: > DOWNLOAD

by Bryan Nichols

Ah, warm water paddling! When winter makes life dark, wet and windy, do you dream of dipping paddle blades into the unmatchable blue of a tropical ocean? You should! Maybe you’ve already got a trip planned for this winter, or perhaps you’re still dreaming.

But where to go? Choosing a tropical destination can be a bit tricky for Northerners—especially since digital photography leaves one resort looking much like another, regardless of where they’re located. Blue skies, green palm fronds, red bathing suits. From a paddling perspective, is the ocean any different in Aruba than it is in Zanzibar?

I have never been to Zanzibar (that’s a song), but I can tell you there are differences. I’ve lived, worked and paddled in the Caribbean, but up until last year I had never visited the South Pacific. In this column we’ll take a look at the differences between two big, warm regions of water—the tropical Pacific and the tropical Atlantic. If you’re lucky, you’ll find yourself paddling in one or both this winter.

BIGGER, BLUER, BETTER
Together, the Atlantic and Pacific Oceans cover more than half the world. The Pacific, in particular, is immense. It’s responsible for one third of the world’s surface (the Atlantic, one fifth). To put that in perspective, let’s hop in our kayaks and paddle from Vancouver, Canada to Sydney, Australia. There’s only a smattering of small islands in that 12,500 km journey. Paddling 30 kilometers a day, seven days a week, it would take us nearly fourteen months to arrive down under. Better bring a fishing rod for food, and how much water can you carry? (Warning: do not actually attempt this trip by kayak!)

Still, the most important difference between the Atlantic and Pacific Oceans might not be their size, but their age. The Atlantic didn’t exist 180 million years ago—that’s when it started to form.

How does an ocean grow? A couple of tectonic plates (the ones you should have learned about in school) split apart. A new ocean appears to be starting right now in Ethiopia. Geologists noticed a four meter rift appear there last September.

Now, 180 million years ago sounds like a long time, and it is. But that would only take you back to the Jurassic, so there were plenty of dinosaurs around before the Atlantic was born. It’s still growing, as spreading plates move the Americas and Africa farther apart each year.

The Pacific has a more complicated history and is both growing and shrinking these days. Many scientists believe the Pacific ‘began’ about 750 million years ago, though there has been ocean in that area for much longer.

The other big difference between the oceans is how much influence land has on them. The Pacific is bigger, sure, but thanks to the whereabouts of the continents, the land area that drains into the Atlantic is four times larger than that of the Pacific. All that fresh, nutrient rich water makes much of the Atlantic a great place to live.

CONNECTIONS
Africa and the Americas cut the warm Atlantic off from the warm Pacific. And as every high school biology student who’s allowed to learn about evolution knows, when populations of animals and plants get cut off from each other, they can change.

If you’re used to one ocean, will the flora and fauna be completely different when you venture into another? For kayakers, many things are the same. You can rest under the shade of coconut palms, for example, just about anywhere in the tropics that gets a decent amount of rain. That wasn’t always the case though. It seems that coconuts originated in the Pacific and have spread relatively recently, with and without the help of people. Either way, they’ve been around the Caribbean now for centuries.

Certain smaller critters have been swimming or drifting through the Panama Canal since we dug it up in 1914. Long before that, sea level changes covered and uncovered the area, letting an assortment of life move back and forth. As a result, you might see some familiar looking jellies, fish and seaweeds if you take a trip to the opposite ocean.

But there are plenty of differences as well. Variety being the spice of life, this list will give you some clues about what to look for. Which destination is better? Each has its charm, its pros and its cons. From a paddling perspective, here are some of the more interesting differences between warm water in the world’s two greatest oceans.

COMPARING THE TROPICS
Diversity
The Pacific is much bigger and much older than the Atlantic, both important factors in biodiversity. How different? Well, Australia’s Great Barrier Reef has over 1500 species of fish on it. Belize, which is blessed with the Atlantic’s longest barrier reef, has 563. The situation is similar for corals and other invertebrates. Under the water, the Pacific’s diversity is astounding. Micronesia is considered by many to have the greatest marine biodiversity on the planet.

Toxins
One of the advantages of paddling an ancient ocean is that the critters have had much longer to evolve. That means you’ll find all kinds of wacky and highly specific adaptations. Unfortunately, it also means the evolutionary arms race has escalated farther. Though critters like snails, octopuses and jellies might seem familiar, there’s a good chance their weaponry is more formidable in the Pacific. Australia, for example, is notorious for its highly toxic box jellies and little blue-ringed octopuses with enough poison to kill a couple dozen people. Pacific reefs even have some pretty snails that can kill you if you grab them. Look, don’t touch.

Sea Snakes
Speaking of poisons, one of the signature marine animals of tropical Pacific waters is the sea snake. You say you’ve seen sea snakes in the Caribbean? That’s hard to say quickly—and anyway, you haven’t. Under water, you might have seen moray eels, snake eels or even snipe eels, but they’re all fishes with gills. Sea snakes are really snakes, air-breathing reptiles that evolved from land-based ancestors. Most of the 70 or so species are related to cobras and notorious for their extremely poisonous bite. Lucky for us they aren’t aggressive, so keep your eyes open and you might be able to grab your mask, hop in the water and carefully follow one. It’s fascinating to watch a snake prowl a shallow reef.

Giant Clams
At some point in my impressionable childhood I saw a lurid drawing of a snorkeler whose foot had been trapped in the wavy ‘jaws’ of a giant clam. It wasn’t until about 30 years and hundreds of dives and snorkels later that I actually saw a giant clam in the ocean. By then, I wasn’t exactly terrified. Though giant clams can grow to 180 kilos (ay caramba!), their grabbiness has been greatly exaggerated. They only live in the Pacific and Indian oceans, so watch for them while kayaking there. Rather than snacking on snorkelers, they have outrageously colorful ‘lips’ containing algae that can make food from the sun.

Clown Fish
Despite what countless t-shirts and souvenirs would have you believe, there isn’t a single species of clown fish in the Caribbean. I don’t care if there’s one on the shirt you bought in Belize or Jamaica, the little ‘Nemo’ look-alikes all hail from the Pacific or Indian oceans. If you get a chance to do some snorkeling there, keep your eyes open for them, especially around big anemones.

Coral
I’ve seen and surveyed a lot of coral in the Caribbean, and one of the first things I noticed about the Pacific was that the coral is just—well, better. More types, more colors, bigger colonies, more impressive shapes—a good Pacific reef is unbeatable. Unfortunately, a good reef, like a good man, is hard to find. Many have been bleached by underwater heat waves and overgrown by drab algae. Coral in every ocean is declining for a variety of reasons, so anytime you come across a healthy, productive coral reef, you should treat it with respect and awe. Don’t touch, but spend as much time paddling, snorkeling and diving there as you can.

Open Water
The Pacific is a really big ocean, and there’s not a whole lot of land in the tropics, especially south of the equator. You can hop a flight from Miami to just about anywhere in the Caribbean and it’ll only take an hour or three to get there. But the Pacific—zounds!—some of those little islands are separated by huge, blue distances. This is the sort of wide open water that most people never experience. Find Easter Island on a globe to see what I mean.

Cyclones
Nervous about visiting the Caribbean during the hurricane season? You should be, especially if you’re planning anything more than a day paddle or two. Don’t think that Pacific destinations are immune though. In the Pacific, you’ll also hear about typhoons or severe tropical cyclones, which are regional names for the same sort of rotating mega-storms. If you’re paddling anywhere in the tropics, or even just vacationing, you should know when the cyclone/hurricane season is and the likelihood of a storm hitting your particular destination.

© Biologist Bryan Nichols spent a month near Tonga and Fiji last year. He’s now in Florida, where the Caribbean is close and has some great paddling, but he also plans to keep exploring the South Pacific. So many islands, so little time.