The Chatham albatross improves its status on a list of endangered species after research reveals the rare species is holding its own, writes Andrew Stone
The Chatham albatross, one of the world's rarest birds, resents visits by seabird researcher Paul Scofield to the windblasted rock they call home.
Their displeasure is plain from the foul fluid they spit at him, so repulsive that after three weeks clinging to the steep rocky flanks of The Pyramid, the research team reek terribly of fish oil.
For Scofield the odour is worth the trouble.
Sorties by New Zealand scientists over the last 40 years to the precipitous volcanic stack just south of the Chatham Islands have confirmed a remarkable conservation success story: the Chatham albatross is no longer critically endangered.
Its numbers are stable and its status has improved to "vulnerable" on the latest Red List of threatened species, the world standard of plants and animals at risk of extinction in the wild.
It was the only threatened New Zealand species to enhance its survival prospects during what scientists increasingly call the "sixth great extinction" - an era noted for the disappearance of plants and animals.
Birds species alone now appear to be vanishing at the rate of about one per decade. Last month's update of the International Union for the Conservation of Nature's Red List recorded the extinction of the Alaotra grebe, a small bird native to Madagascar. Some 132 bird species are thought to have become extinct since 1600.
On The Pyramid however, the resident bird appears to be holding its own.
Counts indicate the population has recovered since a violent storm in 1985 wrecked nests and destroyed eggs. Safe longline practices agreed to by New Zealand fishing companies have dramatically cut the number of birds fatally trapped on hooks towed behind trawlers.
About 5300 breeding pairs of Chatham albatross nest there on cone-shaped lumps made of bones, feathers and rock chips pasted together with guano or bird droppings.
Nests are plastered to ledges and held fast with scraps of vegetation such as ice-plants which somehow survive on the inhospitable monolith.
It is the only place on the planet the birds breed. Nests cover less than one hectare of the speck of rock, with birds on lower slopes exposed to threats of massive swells from the Southern Ocean rolling over the base of the 270m high stack.
Research trips are demanding. Scofield, who has studied seabirds for 25 years, says parties navigate two-metre swells in inflatable boats across kelp-covered rocks to get ashore.
Tents are fixed with pitons hammered into tiny cracks or fastened with large fishhooks in crevasses. Springs attached to guy ropes allow the shelters to stretch in 100km/h gusts.
"We're only about 20m above the sea. In bad storms we get kelp covering our tents and seawater in the door," says Scofield. When it gets really bad the team use rope and harnesses and lash themselves to the rock.
Scientists have to endure being constantly spattered with bird droppings and cope with a constant racket. And then there's that vomit, which Scofield says the birds project as a defence mechanism against human interference and marauding skuas which target vulnerable chicks.
Besides its repulsive smell, the stuff is so toxic that it rots fabric: Scofield replaces his footware after a three-week stay with the birds.
Curator of vertebrate zoology at Canterbury Museum, Scofield has visited The Pyramid since 1999. He followed in the pioneering footsteps of Dr Christopher Robertson who began fieldwork on the bleak offshore island in 1973.
The work of their teams lies behind the improved status of the Chatham albatross on the Red List, as it has produced a far more accurate and consistent assessment of numbers. The total population is estimated to be 10,000 to 11,000 breeding birds.
Robertson, now retired, has spent half a century exploring the life of large seabirds and albatrosses and thinks the outlook for the Chatham's species is relatively secure. He remembers his first trips to the island as a Wildlife Service scientist, and finding a lot more birds than expected.
Estimates until then had relied on Air Force reconnaissance photographs, which missed as many as 25 per cent of the nests, including hundreds on the floor of a cave. Shielded from the harsh elements, the nests had grown as high as one metre.
Robertson watched fascinated as adult birds hooked their beaks over the nests' edges and pulled themselves up. He says the noise in the cave was deafening as the occupants objected to his presence: "I wondered if I would get out alive."
The birds spend summer at The Pyramid, feeding on the rich Chatham Rise fishing grounds, breeding and raising the next generation. New Zealand scientists have learned more about the long-distance flyers from tiny transmitters attached to adult birds.
Data from the devices shows the birds - carried aloft on a 2.5m wingspan - head across the Pacific to South America and up the coast to Peru's rich feeding grounds. They return on a more northerly track, arriving back in their thousands in August to resume the cycle.
The species is long-lived. Birds don't breed until they are 10 or so, and a banded bird recorded in 1973 was alive at least two years ago. But females produce a single egg, which can easily be lost in extreme weather.
He says fishing practices used routinely by New Zealand crews needed to be adopted by South American boats and research on the impact of climate change and El Nino effects - which can halve breeding rates in some years - would help direct conservation work.
All the effort of the last 50 years has made him confident the species is "not in such dire straits. Day after day we're bombarded with stories of populations in decline. This time it's not the case."
