Читать книгу The World Beneath - Richard Smith - Страница 9

In the declining early evening light forty-five feet beneath the surface on a remote Indonesian coral reef, a tiny seahorse strangles another with its tail. Just three-quarters of an inch long, the diameter of a one-cent coin, and perfectly camouflaged against the windshield-sized fan-like gorgonian coral they inhabit, these creatures have a penchant for the dramatic. For my PhD research I spent six months watching and recording the antics of these mysterious and diminutive fish, collecting data on their biology and conservation—the first recorded observations of their social and reproductive behaviors. Denise’s pygmy seahorses had only been recognized by science four years previously, in 2003. Like other behaviors that occur on coral reefs every day, these skirmishes have presumably been happening for millennia. We just didn’t know to look for them.

A red sponge and divers. Wakatobi, Sulawesi, Indonesia.

Most of us hear about coral reefs and see them on nature documentaries, but unless we’re lucky enough to experience such awe-inspiring ecosystems firsthand, it can be hard to appreciate their intricacies. Exploring a tropical rain forest, you drip with sweat in a supersaturated and oppressive atmosphere waiting to spot an animal. A bird might call in the distance, the insect at your feet might unleash its high-pitched whine, and, perhaps, if you’re very lucky, and extremely patient, something larger might barrel toward you from the undergrowth. On a healthy coral reef, you can glimpse activity and life wherever you happen to look. Dozens of fish busy themselves with their daily commutes and travails.

In one hour on an Indonesian reef you will likely see over one hundred multihued and multiform species of fishes, if not double that—scrupulous cleaners, eccentric lovers, steadfast parents. The nervous cometfish pokes its marionette of a tail out of a hole, attempting to convince you it’s a menacing moray eel. Inches from your mask, a small but assertive damselfish warns you not to swim any closer to its precious algal farm. You may not know the names of all of them, but you are mesmerized: immersed in the hustle and bustle of their daily rituals.

Coral reefs continue to surprise and delight. My work has taken me all over the globe and introduced me to coral reefs in twenty-three countries. I have seen fish that wouldn’t even stretch across a dime and others that are longer than two London buses. I have seen vibrant and bustling coral gardens that stretch as far as the eye can see and I have captured the first photograph of creatures that have never before been pictured alive. Elsewhere in the ocean, I have come face to face with a warty file snake deep among the roots of a mangrove forest in Indonesia, photographed animals and behaviors in Japan that were still unknown to science, and spent hours scouring an algal-covered rock face to find an unnamed relative of the seahorse in New Zealand. My aim in this book is to share some of my passion and wonder for coral reefs and the astounding variety of creatures that call them home, while allowing those who aren’t lucky enough to experience this wonderful ecosystem firsthand a window under the waves.

Undescribed species of pygmy pipehorse from New Zealand. Northland, North Island, New Zealand.

For a long time, coral reefs have fascinated mankind. Charles Darwin mused about how these eclectic ecosystems could flourish in crystal-clear tropical waters where there are next to no nutrients to fuel their growth. Today we hear about them in the news—often, articles bemoaning their loss due to devastating coral bleaching. When corals become stressed by environmental changes, such as warmer waters, they expel their symbiotic intracellular algae, leaving them ghostly white in appearance. Coral bleaching has killed millions of corals over the past two decades. Children learn about coral reefs as well, namely through the popular (though scientifically free-willed) animated coming-of-age film, Finding Nemo. I credit the film for this even though its makers didn’t include some of the most fascinating aspects of anemonefish biology in the story line. If the film were true to life then after the untimely death of Nemo’s mother, his father would have transitioned into a female and another sexually reproductive male would have taken his place.

The reef is a biological powerhouse, full of fantastical creatures with amazing stories to be told. For my godson Joey’s birthday, I made a huge print of an untouched coral reef vista that I took in West Papua, Indonesia, to put on his bedroom wall. When I was a child in a rural British village, I spent hours poring over a map of the globe on my friend’s wall; this had a profound effect on my view of the world. I hoped I might inspire Joey, the way I was inspired, that I might foster within him a wonder of the natural world. With so many kids growing up without a tangible connection to nature, it is ever more important for us to celebrate its splendor.

For those lucky enough to dive or snorkel on a coral reef, the first time is as overwhelming as it is memorable. Imagine the European explorers as they came across the first coral reefs. As early natural historians and biologists began to explore coral reefs, they would have been struck by the stark differences between Caribbean, Red Sea, and Indo-Pacific reefs and the temperate Atlantic and Mediterranean ecosystems they were used to. Initially, of course, the extent of an explorer’s interest in coral reefs lay in the reefs’ ability to wreck their vessels. Despite all the modern technology that we now possess, there are still unchartered waters that can scuttle ships. Only a few years ago, I was on a boat that narrowly avoided disaster after encountering an unchartered reef in a remote corner of Papua. I looked over the side of the ship and could clearly see the tiny damselfish on the reef below; they were so close.

The ocean’s largest fish, the whale shark, feeding with a school of mackerel. Cebu, Philippines.

Growing up in England, albeit the most landlocked part, I felt a deep connection with the sea, and I can relate to the wonderment of those early explorers. My connection with it began when my father took me to rummage around tide pools, or rock pools as we call them, on the British south coast. I spent hours hunting between the seaweeds for beadlet anemones, periwinkles, limpets, and the odd hermit crab or shrimp. The life in tropical tide pools tends to be less abundant due to the extremes of heat that the animals must endure in the blazing sun, but if you explore beneath the surface, the differences between coral reefs and temperate seas immediately become clear. So far, more than eighteen hundred different reef fish species have been found and recorded on the reefs of the Raja Ampat Islands, located off the island of New Guinea, in Indonesia’s West Papua province—compared to three hundred around the British Isles. Each reef is different too; while many of the Atlantic fishes are extremely widespread, almost every Indonesian island has its own unique assembly of creatures.

A Raja Ampat coral reef. Raja Ampat, West Papua, Indonesia.

We are living through a revolutionary period in the timeline of coral reef exploration; suddenly, for the first time, scuba allows us to get to know a reef intimately. Citizen scientists, not only academics, are contributing enormously to our understanding of this world. Any motivated healthy adult can get certified within a week to dive down to one hundred feet below the surface and, with a little experience, spend an hour submerged. With the advent of accessible recreational scuba training, we are the first generation that has been able to freely explore the underwater realm. We are diving into and cataloging the Coral Triangle, the region of Southeast Asia where the world’s richest coral reefs reside, ones that have never been explored before. I have been among the first group of divers to explore a certain coral reef—outer space is not the only place where we can “boldly go where no man has gone before.” And as a direct result of expanding our horizons into unchartered corners of the sea, we are discovering a wealth of new species.

You might have thought that scientists have documented almost the whole diversity of the Earth, but particularly in the oceans; this couldn’t be further from the truth. In my twenty-three-year dive career, fish identification books have doubled in size as people push boundaries in terms of what they look for and where they look. This expansion has yet to peak. I recently worked on the scientific description of a new species of pygmy seahorse from Japan; it was hiding in plain sight and not far from Tokyo, the world’s most densely populated metropolitan area. I know of at least one more new species of pygmy seahorse waiting in the wings. The same is true of almost any group of sea animals you care to choose. With so few taxonomists, there are great queues of species that continue to go about their daily lives, but are yet to be formally named or studied.

The complexity of coral reefs is often multilayered and elaborate; while we tend to focus on the prominent corals and fishes vital to the reef’s functioning, they make up just a fraction of the overall number of species. We turn a blind eye to things we consider boring, insignificant, or ugly, such as worms, sponges, sea cucumbers, and parasites. But they are absolutely fascinating in their own right if we spend a little time considering their natural history. I am drawn to animals that are easily overlooked or ignored, and I use underwater photography to share their beauty—hopefully imparting a greater sense of appreciation to people who haven’t been able to see these animals firsthand.

It’s unsurprising that some of the tiniest reef inhabitants are poorly known, but even some of the biggest, most conspicuous, and most charismatic are reluctant to reveal their secrets. In 1986, only 320 whale sharks, the world’s largest fish, had ever been recorded alive; today we know of aggregations of 420 individuals in just a few square miles.1 We still don’t know for sure where these behemoths go to mate or give birth. We don’t know where juveniles spend their formative years; we don’t even know where all the biggest female whale sharks live. Another shark, the megamouth, the world’s third largest, wasn’t even discovered until 1976. We still have fewer than one hundred recorded sightings of the species and know next to nothing about its biology and ecology.

One phenomenon that we must be aware of when it comes to coral reefs, and natural ecosystems in general, is shifting baselines. The first humans to see coral reefs would most likely have experienced them in their pristine state, but sadly our actions take their toll on the health of an ecosystem. Over the years, declines in ecosystems can be masked by perception of what a natural ecosystem looks like, with each generation, our view of how a coral reef should look and function shifts slightly. In 1997, I was lucky enough to catch a brief glimpse of the Maldivian coral reefs before they were completely devastated by coral bleaching. A diver visiting the reefs today might not be aware of the changes that have taken place and consider what they see at face value. The current, depleted state of the reef becomes that person’s baseline. With such widespread bleaching affecting the world’s reefs, one wonders if the next generation may think of their damaged state as the new normal and have a different concept of what a pristine coral reef looks like.

The world’s smallest seahorse, Satomi’s pygmy seahorse, described in 2008. Raja Ampat, West Papua, Indonesia.

Night diving isn’t my favorite pastime but seeing a new creature certainly is. Descending into the darkness down an undulating and jagged reef wall in the most remote corner of West Papua, I was looking for a fish that at that time wasn’t yet named and that I knew would be very hard to find. Unlike the pygmy seahorses that I studied for my PhD research, which live on gorgonian sea fans, Satomi’s pygmy seahorse hops about the reef from gorgonian to hydroid to soft coral. Beyond not knowing exactly where to look for the fish, it is difficult to track the creature because it measures no longer than half an inch in length and is only active as night falls. My dive guide friend Yann Alfian had spotted one for the first time weeks before, so he was eagerly taking me back to try and find it again. Not wanting to disturb these tiny animals with our bright flashlights, we covered all but a fraction of our beams, revealing only a tiny shard of illumination onto the reef. We searched and searched to no avail, but after half an hour, Yann’s little beacon of light finally shined on a tiny seahorse swimming from one frond to another. There is no sense of scale or perspective underwater, but I was amazed at how nature has condensed all the organs needed for life into such a miniscule package. This fish has a brain, gills, and a heart; males get pregnant and brood their young. I ended the dive elated to have observed one of the smallest backboned animals on the planet.

It is impossible to be jaded by the spectacle of a coral reef: the natural world just keeps giving. Throughout this book, I aspire to share a little of my passion for the many creatures and little-known organisms that call coral reefs their home. I hope you can learn how this intricate ecosystem functions while gaining an appreciation for its surprising, beguiling, and charming residents.

1 Rafael de la Parra Venegas et al., “An Unprecedented Aggregation of Whale Sharks, Rhincodon typus, in Mexican Coastal Waters of the Caribbean Sea,” PLoS ONE 6, 4 (April 2011).