Last night the boat’s engines went silent around 3 am. Talking to the crew earlier they said that we would arrive early at Ducie atoll so we would just drift for a few hours until day broke. I got up at 6:30 and I could already see this most southern of all atolls on Earth low on the ocean. A few petrels and masked boobies showed to greet us. Nigel, the owner of our ship, came in to tell us that the crew had seen four dead birds making our approach this morning. I had in mind petrel.
I was in the bridge as we approached. Nigel asked for depths. Neal, the captain, called out 365 meters. He told me the last time they were here the birds were so thick they looked like smoke above the island. No such luck today. When we reached about 50 they dropped the hook and the action began. The inflatable Zodiac boat got hoisted into the water. Nigel and Neal went to go check out our passage to the island. It checked out and in no time they were back and hailing us into the Zodiac. I embarked with Andrew from National Geographic and Heather from Pew Environment Group who would help with the work on the island.
Getting to Know the Locals
Up a channel in the reef and we started unloading. A few minutes later the boat was gone. Looking toward the island I could see it was a pure stand of tournefortia trees. The Pitcariners call them cabbage trees.
There were some petrels flying around the island but my guess was we were dealing with maybe a few thousand birds—not hundreds of thousands. I got an email from Michael Brooke saying that we were at the beginning of the breeding season and that we would be too early to see the mother lode. We were on the lookout, in particular, for the Murphy’s Petrel, which finds its greatest population concentration on Ducie with some 250,000 birds recorded in the early 1990s. The other important species is the Kermadec Petrel with a not very useful population estimate of between 10,000 and 100,000 birds. The other species we would look out for is the Herald Petrel with a population in the thousands.
The thing about petrels though is that “Petrels” is the section of the bird book I have always kind of avoided because they are real hard to ID and I have never been to a place where they breed or with an expert who knows them by heart. Today though, I was going to have to graduate to the major leagues fast.
Before we set up camp we went across to the lagoon. It is circular and a mottled sky- and navy-blue. The water was crystal clear. Right there was a black hole with a whirlpool, a cave that was emptying the lagoon. At water’s edge as soon as we got there we were greeted by three spotted three-surge groupers (Epinephelus socialis). They came to within a foot of the beach in four inches of water and just stayed there. The bigger one chased the others away, as if to say “no, these are my humans”. They must call them socialis not because of their affinity for one another but for human contact. On the quiet lagoon, still no sound of a bird colony.
This was exploration day. I wanted to cover the periphery of what they call Acadia Island, which is the motu, or coral atoll segment, that covers the northern side of the atoll and is by far the biggest of the four land masses. Back where we were going to set up camp red hermit crabs were all over our stuff looking for food (Coenobia perlatus); but here was an addition, the same much bigger and bolder hermit crab (Coenobia spinosus) that we saw on Pitcairn. The big ones there use coconut shells for shelter, but here they use a snail shell that is abundant here (Turbo argyrostomus). There was also a small fly whizzing about in a cloud above our food.
We got our gear together and headed north on the ocean side. The beach was a mix of relatively recent coral rubble along with some limestone plate down at water level. The flats were covered in small sea slugs (Holothuria atra) and small schools of mullets. The flat reef crabs (Graspus tenuicrustatus) were common on the limestone edges. In most places the coral rubble was steep to an upper beach. The cabbage trees started right at the edge.
The first birds we noted going north on the east side of the island were the great frigates sitting in trees and kiting in the island air. There were also some red-footed boobies, fairy terns and a few noddies and petrels that had whitish ventral sides and darkish heads. They were making this surreal whirring vocalization. In the clearer spots there were masked boobies, about half of which were sitting on mostly one egg, sometimes two. The nesting birds sat in the sun, their gullets vibrating, mouths open to stay cool. They seemed more skittish than the ones in the Southern Line Islands.
About ten minutes up the beach we ran across a dead petrel. It seemed to be a fledgling. It was eaten, but probably scavenged by the red hermit crabs as opposed to having fallen victim to some unknown land predator. We saw a couple of wandering tattlers and then more dead petrels, then dead cabbage trees, then a dead masked booby that also looked to be almost fledged.
Under the shade of the cabbage trees we got our first looks at nesting petrels. It seemed to be a mix of adult birds and almost fledged young, some very dark with down still on the neck. They were not abundant but here and there calmly sitting under the shade of the cabbage trees.
Wreck of the Whaling Ship Acadia
The further north we went the more of the cabbage trees were dead. We saw the legs only of an enormous spiny lobster with beautiful purple and yellow stripes. The trash load in general stayed pretty low: mostly fishing floats and bits of rope. We started seeing bits of copper plating like they used to use to patch leaks in the sides of 19th-century sailing ships. One bit even had a crudely formed copper nail. I figured we might have come across the remnants of a shipwreck.
Sure enough we soon came to a monument. It said that just off this point the whaling ship Acadia had wrecked in calm seas in 1881 with no loss of life. The crew took life boats to Pitcairn where two later made their homes. I was happy to see that doing cursory transects can lead you to determine the identity of something about which you were not certain.
As we proceeded north more dead birds and more masked boobies lined the beaches. Fairy terns giving their reverberating rubber band calls mobbed over our heads. We saw a few long-line beacons, but no intact FADs. It would seem that the fishing paraphernalia was coming from far away. We ran into a dying petrel chick that had what looked like a tick on its head. As we neared the end of the motu to the north the cabbage forest was almost completely dead. In the understory of the skeletons of the trees that seemed to have died only in the past year or so was a dense mat of Boerhavia herb (Boerhavia tetrandra). This is a common weed in the South Pacific and has not appeared in previous reports of the flora of Ducie so presumably it’s a new arrival on the island.
Mother Lode of Dead Birds
As we rounded the bend of the spit at the west side of Acadia and turned from the ocean side to the inner lagoon or atoll side, we hit the mother lode of dead birds. I started counting them by 20s, and in a few minutes was up to 254 dead juvenile petrels that had washed up on the high tide line. At the same time over the point we had a group of about 10 red-tailed tropicbirds. Funny that all the tropicbirds we saw in Mangareva were white-tailed and here in the Pitcairn Islands all of them are red-tailed. They were being raucous, sounding like there were probably nests around.
On the atoll side there was pretty much a solid plate of coral all the way along. We hugged the limit of the cabbage trees to keep track of birds. Just past the dead birds we ran into some timbers, actually masts of a ship, probably the Acadia. The one was about 8 inches in diameter, the other about 4. I pulled a chunk off the bigger. It was every bit as aromatic as the day it was cut. It was a cedar of some kind, eastern American or European—not sure which. There was a big iron band around the one and lots of heavy iron debris and spikes that were starting to disappear, but pretty impressive considering they have been sitting on this beach for well over a century.
We hit another big patch of dead birds, 190 in total, all juvenile petrels of at least two species. Then there it was: a single bush of a species of shrub called Pemphis acidula, a widespread species in the south Pacific, which is the only other plant species ever recorded on this small island. Amazing that just about everyone that has ever been here it would seem has found this same individual and added it to the flora. Petrels continued to buzz over. I was wondering if between the different color phases and ages if I would possibly be able to figure out these birds in just a couple days and produce any worthwhile data.
Back to Camp
We arrived back in camp very thirsty; amazing how these islands heat up in the day. In the PM I did a tour around the southern end of Acadia motu. Same combo of birds in the trees: fairy terns, great frigates, masked boobies, some nesting (some not), petrels buzzing, red-footed boobies on the cabbage trees and a few wandering tattlers along the beach. There seemed to be fewer petrels on the ground, holed-up under the trees. On the way back on the lagoon side on the hard limestone plate that extends out quite a ways as the sun was going down I got a coterie of about 45 masked boobies hanging out together, looking uninterested in one another and yet together. What is that about?
On my way into camp the groupers came to greet me like my pets. I could feel that I burned the back of my legs. We are back on the islands now.