Our excellent adventure at Palmyra Atoll is now over, and we have all returned home.
What an amazing two weeks — Palmyra is one of the most spectacular places I’ve ever been. Some of my most enduring memories of the atoll will be the hundreds of thousands of seabirds, healthy and luxuriant coral reefs, and the large numbers of sharks, manta rays and other reef fishes.
It was also a great pleasure to help the Palmyra team develop The Nature Conservancy’s first monitoring program for the atoll, and I’m confident that what we learn there will help us strengthen conservation for islands and coral reef ecosystems globally, particularly in the fields of climate change, fisheries, and coral reef restoration.
By purchasing Palmyra, the Conservancy has provided a strong basis for protecting this extraordinary place. However, further actions are now required to ensure the effective conservation of the entire atoll and its wildlife in the long term. Of particular importance will be helping Mother Nature restore the lagoon and island systems to a more natural state, by removing man-made obstructions to water circulation and eradicating or controlling introduced species (particularly rats, scale insects and coconut palms).
While it was sad to leave Palmyra, we had a spectacular flight home over some of the Line Islands — Teraina (Washington Island), Tabuaeran (Fanning Island) and Kiritimati (Christmas Island). Flying over these atolls provided a wonderful perspective on the scale of the Line Islands — a group of 11 atolls and low coral islands stretching over thousands of miles of the Central Pacific.
Eight of these reefs and islands belong to the Republic of Kiribati, and three are territories of the United States (Palmyra Atoll, Kingman Reef, and Jarvis Island). Since the U.S. territories are all part of the Pacific Remote Islands Marine National Monument, they provide an excellent basis for establishing a large scale network of marine protected areas that links up the far-flung reef systems of the Line Islands with others in the Central Pacific.
(Image 1: Fanning Island, Republic of Kiribati. Credit: Kydd Pollock/TNC. Image 2: Kingman Reef, Pacific Remote Islands Marine National Monument. Credit: Kydd Pollock/TNC.)
Shark: Just the word seems to strike fear in the heart of most people, and for good reason — sharks kill and maim people every year.
However, while some species are dangerous, many are mild-mannered and pose no threat to humans. This is particularly true on coral reefs where most sharks are small (less than six feet long).
Sharks are slow growing, long-lived and slow to reproduce, so they are particularly vulnerable to overfishing. Consequently, they are becoming increasing rare on most of the reefs of the world.
That is one of the reasons that Palmyra is so special. Sharks are protected here, and there are a lot of them. We see them everywhere we go — mostly black and white tipped reef sharks, but also lots of grey reef sharks. These sharks are generally small (less than six feet long), but some are eight feet long.
Yesterday we went to a dive site called “Hammerheads” to see a completely different kettle of fish – hammerhead sharks. They grow up to 14 ft long, and are considered dangerous to humans.
When we entered the water, we were quickly surrounded by grey reef sharks, which raced up to us and spent the next hour swirling around us. It was hard to work out exactly how many there were, but I could see at least 12 (each six to eight feet long) at any one time so there must have been a lot more. Grey reef sharks are very inquisitive, and often swim right up to you, which can be a bit disconcerting if you’re not used to it. Sometimes they can be aggressive, but mostly they are just curious — cruising past, around, over and under you.
Then suddenly there it was — a hammerhead shark. It was huge, probably 12 ft long and twice the size of the other sharks. Wow, what a sight! They are magnificent creatures, slightly menacing, but wonderful to see and mesmerizing to watch. What a privilege and a rare treat it is to see them these days.
Is there anything cuter than a baby booby bird? Large white balls of fluff perched in the trees and on the ground, all watching you with that slightly crazed look in their eyes.
While the adults are quite refined, the juveniles are anything but. They are extremely curious and follow us around everywhere we go in the boats, flying low over our heads. If we put our hands up, they try to peck at our fingers or land on them. They also love to peck at the antennae on our dive boat, Zenobia, and if we are moving slowly enough, they come in and take turns pecking at the antennae in mid-air.
On Palmyra, we consider it good luck to be pooped on by a booby bird. But since there are so many of them, and they hover over us, it’s a really good idea to keep your mouth closed when you look up!
But perhaps the funniest thing is the way they land and put their heads under the water to watch us while we are diving. The first time I saw this I thought: “What on earth is that?” And then I realized — those crazy birds had followed us underwater as well!
(Images: Top: A fluff ball (a baby red-footed booby bird). Bottom: A red-footed booby above our dive boat. Credit: Kydd Pollock/TNC; Kim Hum/TNC.)
The tropical oceans of the world comprise four major biogeographic regions: the Indo-West Pacific, Eastern Pacific, Western Atlantic and Eastern Atlantic. These four regions show considerable variation in species composition and diversity, resulting from differences in their evolutionary history and oceanographic conditions.
Of these, the Indo-West Pacific, where Palmyra is located, is by far the most diverse.
This region is very large, and comprised of several sub-regions where endemic (locally restricted) species can be found. One of these is the Central Pacific, which includes Palmyra.
Consequently, the reef fishes of Palmyra are a mixture of widely distributed Indo-Pacific species, such as the Redfin Butterflyfish (Chaetodon lunulatus), and species that are endemic to the Central Pacific.
As a self-confessed fish geek (the marine version of an avid bird watcher), I’ve spent many hours making species lists of reef fishes, and looking for new species to add to my lifetime list wherever I go. So one of the reasons I was excited about coming to Palmyra was to see species that I haven’t seen before.
Palmyra did not disappoint me, and I have added nine fish species to my lifetime list. Some of which are very colorful and beautiful such as the Golden Gregory (Stegastes aureus), while others have more drab coloration such as the Central Pacific Coris (Coris centralis) and are not nearly as glamorous. But it’s all the same to me — I love to see them all.
(Images: Redfin Butterflyfish, Palmyra (top) and Golden Gregory, Palmyra (bottom). Credit: Kydd Pollock/TNC.)
During World War II, Palmyra was one of many atolls that became a U.S. Naval air station, undergoing extensive modifications including (a) dredging a deep channel between the ocean and lagoon, and (b) dredging and filling to expand and link the islands via causeways.
This reduced circulation in the lagoon dramatically and seriously degraded coral reef communities within the lagoon.
In the seven decades since this construction, Mother Nature has started to reclaim the atoll by eroding away the causeways and establishing new circulation patterns in the lagoon.
Jim Maragos of the U.S. Fish & Wildlife Service, a member of our expedition, has been studying the reefs of Palmyra for 30 years. “When I first visited Palmyra, I found a heavily modified lagoon system with very little life,” he told me. “Since then, several breaches have occurred in the causeways that have increased water flow between the lagoons. Unfortunately, they are also sending hot turbid lagoon water over shallow reefs outside the lagoon.”
“When the breaches occurred, these shallow reefs were healthy with literally miles of lush coral growth east and west of the lagoon.” he added. By 1998, he realized these new, unnatural flow conditions were also killing corals outside the lagoon.
“Removing part of the north-south causeway to provide more natural circulation patterns is a high priority for protecting Palmyra’s coral communities, especially its famous Coral Gardens,” said Jim.
Should we give Mother Nature a hand and help her restore more natural patterns of circulation around the reef? Or should we let her continue to find her own way, which may cause more harm to coral communities?
(Editor’s note: Alison Green, senior marine biologist at The Nature Conservancy, is spending the next two weeks diving and exploring Palmyra Atoll as part of the first marine assessment of the atoll. Follow her posts from Palmyra on Cool Green Science…and learn more about the expedition.)
Climate change presents a huge threat to coral reefs, particularly warming seas that have already caused mass coral bleaching and mortality worldwide, including at Palmyra. In 1998, the world’s reefs experienced the worst coral bleaching event on record, which led to the loss of nearly 20 percent of the reefs of the world.
Rod Salm, who leads our Asia Pacific marine team, has spent the last two decades studying the effects of coral bleaching — and helping marine-resource managers understand how to respond to this threat.
Rod’s role in this expedition is to determine the impact of climate change on the reefs of Palmyra, and the prognosis for their long term survival.
Rod told me today: “Over the last week, I’ve seen a mosaic of healthy, lush, resilient reefs and some that have been heavily impacted by both coral bleaching and WWII dredging and coastal construction.”
“Looking forward, the uplifting feature is that there are still areas of vibrant, vigorous coral growth that have the strong indicators of resilience that reefs need to recover from past disturbances and survive into the future.”
But how does he know that? What are the ingredients of coral reef resilience so apparent here at Palmyra?
(Editor’s Note: Alison Green, senior marine biologist at The Nature Conservancy, is spending the next two weeks diving and exploring Palmyra Atoll as part of the first marine assessment of the atoll. Follow her posts from Palmyra on Cool Green Science…and learn more about the expedition.)
Large groupers (like the one above) are very susceptible to fishing pressure.
Along with sharks and other large reef fishes (particularly bumphead parrotfish and humphead wrasse), large groupers are often the first to disappear when reefs are fished. In fact, these species are so vulnerable to overfishing that they disappear even when fishing pressure is light.
In recent years large groupers, parrotfishes and wrasses have also been targeted by the live reef food fish trade, which has decimated their populations throughout much of Southeast Asia and the Western Pacific. Large groupers are particularly vulnerable to overexploitation because they aggregate to breed (in groups of hundreds or thousands), so it is possible to catch all or most of the population at one time.
Consequently, it is a rare treat to see large groupers these days, and when you do, you usually only get a brief glimpse of them before they race away and hide.
So imagine my surprise today when I saw three camouflage groupers(Epinephelus polyphekadion), 40cm to 50cm (16 to 20 inches) long, and completely unafraid of me. When I first saw them I froze, expecting them to race for cover at high speed. Instead, one of them swam slowly towards me until it was just inches away from my mask staring me straight in the eye as if to say: “Yes, what do you want?”
It was a wonderful experience and will be one of my most treasured memories of Palmyra, a place where large groupers are not afraid of people.
(Image: Camouflague grouper, Palmyra. Credit: Jim Maragos, USFWS.)
(Editor’s Note: Alison Green, senior marine biologist at The Nature Conservancy, is spending the next two weeks diving and exploring Palmyra Atoll as part of the first marine assessment of the atoll. Follow her posts from Palmyra on Cool Green Science…and learn more about the expedition.)
When you land at Palmyra Atoll, one of the first things you notice is the outrageous number of seabirds.
Great and lesser frigate birds; brown, masked and red-footed boobies; white- and red-tailed tropic birds; sooty and white terns; and black and brown noddies — all forage over hundreds of square miles of ocean using the atoll as their home base.
Today, we spent the morning exploring the lagoons and viewing the birdlife. And what I saw was spectacular.
My favorite was the male frigate birds (like the one above) ostentatiously displaying their red neck pouches for the girls. How those huge birds fly with large red balloons attached to their necks I’ll never know.
Some species — such as red-footed boobies, white terns, and frigates — nest in native trees, particularly Pisonia grandis, Pandanus, Scaevola (Naupaka) and the tree Heliotrope (Tournefortia argentea). Other birds on the atoll — such as sooty terns (in the image directly above), red-tailed and white-tailed tropic birds, and brown and masked boobies — nest on the ground.
But while seabirds are thriving at Palmyra, there are some serious threats to their long-term survival. One of the biggest concerns is introduced species — especially rats.
(Editor’s Note: Alison Green, senior marine biologist at The Nature Conservancy, is spending the next two weeks diving and exploring Palmyra Atoll as part of the first marine assessment of the atoll. Follow her posts from Palmyra on Cool Green Science…and learn more about the expedition.)
Have you ever seen a giant manta ray (Manta birostris)?
They’re huge, majestic creatures with wing spans of up to 22 feet (6.7 meters) across. They glide effortlessly through the water column with their mouths open feeding on plankton.
Unfortunately, in many places in the world. manta rays are killed by local fishermen, either intentionally or accidentally. But here at Palmyra Atoll they’re protected, so there are a lot of them. And I mean A LOT of them.
Today we went on two drift dives through the channel from the outer reef into the lagoon — channels are always a great place to see sharks, rays and other big reef fishes. There were so many manta rays that now I call it Manta Ray Alley.
On each dive we saw at least 10 mantas, which swam right up to us, and did pirouettes around and over us. I could have reached out and touched them.
Lots of mantas swirling around you is a magnificent sight, but it makes them difficult to count. Fortunately, each manta ray has distinctive markings, so it is possible to identify individuals. One of the Nature Conservancy staff in Palmyra, Kydd Pollock, has been building up a photo library of manta rays, so one day we hope to have a better idea of how many there are at Palmyra.
Because manta rays feed on plankton, and plankton is attracted to lights, the mantas also come into the boat harbor at night to feed under the lights. At Palmyra, we spend our evenings watching manta rays feed beside the jetty, which is much better than watching the telly!
(Video: Manta Ray at Palmyra Atoll. Credit: Eric Conklin.)
The outer reefs of Palmyra and nearby Kingman are famous for having some of the most “pristine” reefs in the world, particularly populations of large predators — sharks, jacks and other reef fishes that are now rare or absent from many reefs. For a fish biologist like me, it is paradise.
(Editor’s note: Alison Green, senior marine biologist at The Nature Conservancy, is spending the next two weeks diving and exploring 
