Back from the brink: endangered species successes

KNOWN LOCALLY AS ‘AL MAHA’, the Arabian oryx (Oryx leucoryx) is a regal-looking beast that features in Arabic poetry and paintings. Once common, this large antelope has wide hooves that allow it to move across shifting sands, and the reputed ability to smell water from many kilometres away. During the 20th century, hunting took a heavy toll and when the last wild individual was shot in 1972, the species was declared ‘extinct in the wild’.

The Arabian oryx was once extinct in the wild, but a captive breeding program has seen this animal brought back from the brink. (Photography: MathKnight (Wikipedia))

That could have been the final chapter of the oryx’s story, but the species was of symbolic significance to many in the Arabian peninsula. A few animals, caught as wild numbers dwindled, were brought together with oryxes from royal collections in Abu Dhabi, Qatar and Saudi Arabia. Successful breeding programs saw the captive herd grow. In Oman in 1982, the first oryx were reintroduced to their traditional lands.

In June 2011 the International Conservation Union, IUCN, announced that the number of wild oryx had hit the 1,000 mark and that the species was well on the way to recovery. It has been reclassified from ‘endangered’ to ‘vulnerable’ – the biggest success ever for an animal that was once classified as ‘extinct in the wild’.

“To have brought the Arabian oryx back from the brink of extinction is a major feat and a true conservation success story,” said Razan Khalifa Al Mubarak, director general of the Environment Agency-Abu Dhabi. “One which we hope will be repeated many times over for other threatened species.”

Captive breeding programs have had notable successes in many parts of the world. In the US a private captive breeding program brought another large, iconic beast, the American bison (Bison bison), back from the edge of extinction in the late 1800s. Today around 30,000 live in the wild, while another 30,000 are found on commercial ranching operations.

In Australia the helmeted honeyeater (Lichenostomus melanops), a beautiful yellow and black creature that is the bird emblem of Victoria, dwindled to as few as 50 individuals in 1990. A captive breeding program at the Healesville Sanctuary has seen this bird saved from going over the brink. Although it only numbers 80 even now, the 20 or so birds released each year are keeping this species alive, and volunteers are working around the clock to help this number climb.

In Australia captive breeding efforts alone are not always effective because feral species such as cats and foxes have rendered habitats unsafe for captive-bred animals to be returned to. In some of these cases, captive-bred populations have been transferred to islands: either islands in the literal sense, or fenced off habitats from which the predators are excluded.

The greater stick-nest rat (Leporillus conditor) was once common across a large part of arid Australia, but by the 1930s it was extinct on the mainland, remaining on only two islands off of South Australia.

“A captive-breeding program was set up at Monarto Zoo by the National Parks and Wildlife Service and animals released onto another island from which all feral cats had been removed. Further releases have occurred on several other islands…with animals also released into mainland ‘islands’ or fenced reserves,” says Wendy Foster manager of conservation programs at Zoos South Australia. “The species is now listed as ‘vulnerable’, an improvement from its ‘endangered’ listing in 1996, and thankfully a movement away from the ‘extinct’ status that it was looking like sharing with the lesser stick-nest rat.”

Some animals are taken off the ‘extinct’ list after a sudden rediscovery. Just this year, the rainbow toad of Borneo (Ansonia latidisca) was rediscovered 90 years after it was last spotted. And last year, the ‘extinct’ yellow-spotted bell frog (Litoria castanea) was rediscovered 30 years after it went missing in the southern tablelands of NSW. Careful management of such species is necessary to ensure these serendipitous discoveries are not mere blips in the species’ eventual demise.

A sometimes controversial method for conserving species is finding some way to give them an economic value, and thereby letting the market for them drive their survival, as happened with the meat industry for the American bison. Other examples might be breeding a species for sport hunting (the white rhino) or creating an ecotourism industry around it (the humpback whale).

“A realistic conservation project will enable sustainable harvesting by local human communities rather than locking away resources local communities rely on,” says Foster, referring to the conservation of endangered species in developing nations.

However the principle can be applied in developed countries too. The ancient Wollemi pine (Wollemia nobilis) that was known only from fossils until 1994 was discovered alive and well in a number of gorges in Wollemi National Park, 150 km from Sydney. Starting in 2006, cultivated specimens were passed on to botanic gardens and now green-fingered Australians can buy them to plant in their own gardens – thus ensuring this ‘critically endangered’ species a much more secure future.

Sometimes conservation efforts are as simple as putting regulations in place to stop the decline of species. In the lower US states, the bald eagle (Haliaeetus leucocephalus) was reduced to about 400 breeding pairs in the mid-20th century, largely due to poisoning from the pesticide DDT. But with legislation to protect the species and also the banning of DDT in the 1970s, the species rebounded in spectacular fashion. With the population likely numbering more than 100,000, including Canadian and Alaskan birds, in 2007 it was taken off the US federal endangered list.

WWF Australia’s Michael Roache argues that some of the biggest conservation successes of the last 50 years are much more broad-scale efforts than those focused on single species. Some of the top ones on his list include: the moratorium on commercial whaling in 1982 and the regulation of international trade in endangered species with the creation of CITES (the Convention on International Trade in Endangered Species) in 1976.

Conservation successes don’t tend to get as much play in the media as the failures, but reporting on them is vital to give people hope that conservation can succeed, say Australian conservation scientists David Lindenmayer of the Australian National University and Stephen Garnett of Charles Darwin University.

In a letter to the journal Trends in Ecology and Evolution in December 2010 they argued that the “relentless communication of an impending mass extinction is, self-evidently, having insufficient impact on politicians, policy makers and the public, and could eventually even be counterproductive.” They went on to say that “Although we readily acknowledge the immense challenges facing global biodiversity, some conservation achievements of the last half century are extraordinary and inspirational.”

Examples they put forward of some of the biggest successes are in: South Korea, which was almost denuded after the Korean War, but now has 63 per cent forest cover; Namibia, where populations of wildlife are increasing; Iraq, where engineers have re-flooded the vast Tigris-Euphrates marshes; and here in Australia, where the worst of land clearing has been halted and most rainforest is protected in World Heritage sites.

“Given that pessimism is as infectious as enthusiasm, a failure to acknowledge the major conservation achievements to date could mean that prophecies of doom might become self-fulfilling,” wrote the scientists. “Hope is vital to the prospects for biodiversity conservation in coming decades.”

Giving people hope that conservation can succeed is a “very important point,” comments Jean-Christophe Vié, Deputy Director of IUCN’s Global Species Programme. “We need to convince all sectors of society that they can do something. The general public can support the work of local NGOs, can decide to buy responsible products and can vote for the politicians who show an interest for the environment. The private sector can reduce their footprint, source their products properly and contribute financially to conservation.”

Speaking at the Convention on Biological Diversity in Nagoya, Japan last year, Thomas Brooks, on the steering committee of IUCN’s Species Survival Commission, said that “thanks to the efforts of biodiversity conservation… over the last three decades, 20 per cent of the biodiversity loss that would have happened has been prevented.”

“We’re not doing anything like enough,” he admitted, but these successes have given scientists a very good idea of what is needed for efforts to succeed. “We know what to do, we have the answers, we know how to prevent extinctions, we know how to turn around the tide to stop species from getting rarer,” said Brooks. “We just need much more of it; we need the financial mechanisms to support it and we need the implementation on the ground from the local communities around the world…Conservation can work, we just need to get on and do it.”

Author: John Pickrell
Source: ABC Environment



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