Introduced predators such as rodents and feral cats—the islands have no native land mammals—pose a danger, especially to defenseless chicks, which are left alone for long periods while their parents shuttle back and forth from distant feeding grounds. In one of the most extreme examples of seabird predation, mice on Gough Island, in the South Atlantic, are decimating the populations of petrels and albatrosses that breed there, killing an estimated 1, Tristan albatross chicks a year.
Natural disasters also cause heavy losses. In , storm surges washed over two royal albatross breeding islands in the Chathams, killing chicks and, even more problematic, removing much of the islands' scant soil and vegetation. With the albatrosses lacking nesting material in subsequent years, the breeding success rate dropped from 50 percent to 3 percent: the birds laid their eggs on bare rock, and most eggs were broken during incubation. Yet the most pernicious threats to albatrosses today are not to chicks but to adult birds.
Along with other seabirds, they are locked in a competitive battle with humankind for the food resources of the sea—and the birds are losing. This is not just because of the efficiency of modern fishing practices but because fishing equipment—hooks, nets and trawl wires—inflict a heavy toll of injury and death.
John Croxall, a seabird scientist with the British Antarctic Survey, has described the decrease in numbers in some albatross species as "catastrophic. Over the past two decades, high-tech tracking devices such as the GPS loggers used by Scofield on the Pyramid have begun to fill in gaps in our knowledge about where albatrosses roam and where they are coming into lethal contact with fishing operations. Previously, when an albatross flew away from its breeding island, it virtually disappeared, its activities and whereabouts unknown.
But now the lives of these birds are being revealed in all their unimagined complexity, stunning accomplishment and tragic vulnerability. GPS loggers can give a bird's position to within a few yards. Some loggers also have temperature sensors. By attaching them to the legs of their study birds, scientists can tell when the birds are flying and when they are resting or feeding on the sea, because the water is generally cooler than the air.
As nifty as GPS loggers are, there is a snag: you have to get them back—an outcome by no means guaranteed. Among the larger albatrosses, chick-feeding forays can last ten days or more and encompass thousands of square miles of ocean.
Lots of things can go wrong on these outings, particularly in and around commercial fishing grounds, where birds die by the thousands, done in by hooks, nets and the lines that haul them. And because albatrosses have to struggle to take flight in the absence of a breeze, birds may be becalmed on the sea.
The Chatham albatrosses' feeding forays tend to be relatively short—only a few days—and there was little chance of his birds becoming becalmed in the windy latitudes they inhabit, meridians known to mariners as the Roaring Forties, Furious Fifties and Screaming Sixties. More worrisome to Scofield was the knowledge that the area adjacent to the Chatham Islands—known as the Chatham Rise—is one of New Zealand's richest commercial fishing grounds, replete with orange roughy and several other deep water species.
Albatrosses, too, know where fish are found, and the birds sample the most productive fishing areas much as human shoppers make the rounds of favorite stores. And what expeditions these birds make! From mollymawks, as the smaller species are known, to the great albatrosses, these super-soarers cover tens of thousands of miles in their oceanic forays. Individuals of some species circumnavigate the globe, covering miles a day at sustained speeds of 50 miles per hour.
And then they somehow find their way home—even when home is an outpost in the ocean like the Pyramid, not much bigger than an aircraft carrier. At the start of their breeding season, albatrosses have been tracked making almost ruler-straight trips from distant foraging areas to their nests. Because the birds maintain their course day and night, in cloudy weather and clear, scientists believe they use some kind of magnetic reckoning to fix their position relative to the earth's magnetic field.
The birds also seem able to predict the weather. Southern Buller's albatrosses were found to fly northwest if a low-pressure system, which produces westerly winds, was imminent, and northeast if an easterly wind-producing high-pressure system prevailed. The birds typically chose their direction 24 hours prior to the arrival of the system, suggesting they can respond to barometric cues.
In his autopsy room in Wellington, ornithologist Christopher Robertson slit open a plastic bag containing a white-capped albatross. The swan-sized carcass had been thawing for several days. Along with dozens of other seabirds in Robertson's freezers, this one had been collected at sea for the government's fisheries science program. Robertson carefully unfolded the bird's wings—wings that would have carried it halfway around the world, between its breeding grounds in New Zealand's Auckland Islands and its feeding grounds in South African seas.
The albatross bore a raw wound at the elbow. Its feathers and skin had been rasped down to bare bone, presumably by the thick steel wires—called warps—that pull a trawl net. Of the 4, albatrosses and other seabirds Robertson's group has autopsied over nine years, nearly half have been killed by trawl fisheries, which use giant sock-shaped nets towed at depths of a quarter mile to capture 40 tons of fish in a single haul.
Albatrosses and other large, soaring birds tend to die as a result of collisions with the warps, while smaller, more agile fliers such as petrels and shearwaters are more likely to get ensnared in nets—to be crushed or drowned—while feeding.
The finding has surprised the fishing industry and conservation groups, which have considered longline fishing—in which thousands of baited hooks are fed out behind the fishing vessel—a greater threat to seabirds.
There are no reliable figures for the number of birds killed per year through contact with commercial fishing operations, but estimates for the Southern Ocean are in the tens of thousands. Vessels in well-regulated fisheries are required to minimize their impact on seabirds and report any accidental deaths, but there is a large shadow fleet of illegal, unregulated and unreported IUU vessels operating outside the regulations, answering to no one.
Many New Zealand fishers have adopted ingenious methods to reduce injuring and killing seabirds—or attracting them to boats in the first place see sidebar, opposite. However, there is some evidence to suggest that fisheries may benefit albatross populations: a ready supply of discarded fish reduces competition for food between and within albatross species and provides an alternative food source to predatory birds such as skua, which often attack albatross chicks.
Sagar and Stahl's research in the Snares Islands suggests that the free lunch boosts the number of chicks that fledge in a given year. They found that 70 percent of feedings brought by adult birds to their chicks contained discards from nearby fisheries. Does this mean that fishing is a net benefit to seabird populations?
Should the industry be given "a conservation award for the thousands of seabirds it supports," as one fisheries consultant gamely suggested to me? Not at all, says Stahl. In albatrosses—long-lived, slow-maturing species that produce a single chick every one to two years—the long-term negative impact of adult death far outweighs the short-term benefit of chick survival.
It may take three, four or even five successful chick rearings to compensate for the death of just one parent, says Stahl. He calculates that "even small increases in adult mortality can wipe out the benefit of tons of discards fed to chicks. Although Scofield's tracking of Chatham albatrosses shows that they, too, frequent the same fishing grounds as deep-sea trawlers, not enough work has been done to compare the benefits of chick survival with the costs of adult deaths from fishing vessels.
One albatross population that has unashamedly been propped up is the colony of endangered northern royal albatrosses at Taiaroa Head, near the city of Dunedin, on New Zealand's South Island. Taiaroa Head is one of the only places in the world where a visitor can get close to great albatrosses. The colony is tiny, with only individuals, and the breeding effort is managed assiduously—"lovingly" would not be too strong a word. Royal albatross chicks are nest-bound for nine months.
Providing meals for these chicks is so demanding that the parents take a year off before breeding again. Lyndon Perriman, the senior ranger, described to me some of the ingenious techniques used to maximize reproductive success. But we prefer not to interfere. It could simply be that the partner has hit a patch of calm weather somewhere and is struggling to get back. But at day 20 it's pretty clear the partner isn't coming back, and a chick with only one parent won't survive, so we take the fiberglass egg away, and the bird figures out that breeding for that year is over.
Adult birds at Taiaroa have died of heat exhaustion, so rangers turn on sprinklers during hot, still days. There was no danger of the birds overheating when I visited, with raindrops spattering the tinted windows of the observatory.
I picked up a toy albatross, a life-size replica of a fully grown chick. Jordan is fascinated with these majestic birds. Albatross is slow-paced, poignant and poetic.
Lying somewhere between arthouse film and narrative documentary, it was eight years in the making; Jordan spent 94 days on Midway over the course of eight visits.
His lens lingers on moments of natural beauty, tuning into their behaviour and losing track of time. But at the halfway point, everything can change — at half-time, a football coach tells his team that the game is not over yet. Jordan muses that albatrosses — with a brain the size of a walnut — experience the passage of time more slowly than we do.
He films their bonding ritual in slow motion, focusing on the dedication between males and females. These bonds last a lifetime, sometimes more than 60 years. After five months, the fluffball chicks develop into comic, goofy-footed fledglings ready to take flight and begin their first 10, mile-long feeding frenzy over the open ocean.
But some fail to take to the skies and the resulting deaths are often slow and painful. Yet plastic is found in every single albatross bolus or regurgitated mass of squid beaks that chicks produce. Here, nothing stands in our way. Perhaps we need something more emotive to shock us into action.
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