Elephant extinction

15 June 2011 Last updated at 09:48 By Victoria Gill Science and nature reporter, BBC News Forest elephants are smaller than their savannah-dwelling cousins and have straighter tusks The fate of the forest elephant rests in our hands. But will it go the way of the woolly mammoth, as it is hunted for ivory and its habitat is destroyed?

Have you ever wondered why hawthorn trees have such vicious thorns? Like many spiny plants, this is a defence they have evolved to avoid being eaten - by giant herbivores, including elephants.

Throughout the UK there are similar evolutionary clues nodding to the not so long-extinct plant-eating giants that once roamed here.

Up until about 15,000 years ago modern elephants' ancestors - mammoths, mastodons, gomphotheres and a host of other elephant-like mammals - were spread throughout the globe.

Mammoths were "just a species of elephant," says Professor Adrian Lister of the UK's Natural History Museum.

"And until the end of the Pleistocene, there were millions of them throughout the globe, including in northern Europe and North America."

Continue reading the main story Last year, scientists confirmed that forest elephants were genetically distinct from African savannah elephantsForest elephants have straighter tusks and more rounded ears They also share features with Asian elephants with five toes on the forefeet and four toes on the hindfeetBut, as the climate shifted, their open grassland habitat was invaded, either by forests or tundra.

"That loss of habitat squeezed the species down into small fragmentary populations," says Professor Lister. "And human hunting may have helped mammoths on their way to extinction once they were in this perilous state."

Now, it seems, we could be repeating history.

Under siege

The remaining three elephant species have been squeezed down into three areas - Asia, the African savannah and the forests of central Africa. And as well as the endangered Asian elephant, the relatively diminutive African forest elephant - only recently shown to be a distinct species - is now in crisis.

Forest elephants' habitat protected them, to some extent, from the "ivory holocaust" of colonial times

Forest elephants in Africa, to some extent, escaped the "ivory holocaust" during colonial times, and the widespread slaughter of their savannah-dwelling cousins for their ivory in the 1970s and 1980s. This was largely because they were hidden away in their obscure forest habitat in the vast Congo Basin.

Stephen Blake is an elephant expert from the Max Planck Institute for Ornithology in Radolfzell, Germany, who worked on forest elephants for more than a decade for the US-based Wildlife Conservation Society (WCS). He says that this habitat is now being chopped up.

"Forest elephants need vast uninterrupted areas of wilderness to range through.

"But as logging and resource extraction become more important in the region, the animals are squeezed into smaller pockets of forest where they become easily accessible to poachers.

"There are no good estimates of how many forest elephants remain - probably some tens of thousands, but they are being poached at an alarming rate."

Road-building is fragmenting the forest elephants' habitat

Surprisingly, the biggest problem is not the destruction of forest habitat for logging - although this is damaging. It is actually the construction of roads that is doing the most damage to the species.

Kate Evans, a US conservationist and founder of the charity Elephants for Africa says: "The roads go straight through the heart of the forest, so they also provide easy access for poachers."

And where these roads are not protected by law enforcement, forest elephants are petrified of them.

Dr Blake explains: "If you put a 20 mile ring of death around your house, the chances are you won't want to go more than 15 miles from home.

"And if that ring [closes in], you're going to feel besieged.

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I think the extinction of the mammoth is a salutary lesson that applies to modern extinctions”

End Quote Professor Adrian Lister Natural History Museum "You won't be able to go to the places you need to, you won't be able to see your friends, you will become imprisoned, and most likely the food will start to run out. It's just like that with forest elephants."

The illegal ivory trade - fuelled by civil unrest and organised crime in some central African countries - supports the poaching.

Kate Evans says that forest elephants' relatively straight and dense tusks are highly attractive to carvers and poachers.

"Most of the market is in Asia," she says. With a growing middle class that have access to cash, we have seen an explosion in the demand for ivory there."

According to Traffic International, the wildlife trade monitoring network, organised criminal gangs in Asia are shipping large quantities illegal ivory from Africa.

While in central Africa, ivory products are openly sold in village shops.

In some central African villages, shops openly advertise elephant-hunting munitions 'Empty forests'

Just as these giants need their forest, the forest needs them. Dr Blake describes the elephants as "mega-gardeners".

The researcher and his colleagues spent several months camping in the dense forests tracking the elephants. He has found that, during their lumbering treks, forest elephants can vacuum up hundreds of pieces of fruit from under a single tree.

They then deposit the seeds they have eaten with a generous helping of fertiliser - in the guise of elephant dung - throughout the forest. Another side effect of their fruit-rich diet is that they probably defecate around 17 times per day.

"Almost every pile of elephant dung contains viable seeds from up to 16 different plant species and thousands of individual seeds," says Dr Blake.

"Tropical forests are so diverse that a seed that lands near its parent plant has a suite of seed predators and pathogens waiting to nab it," he explains.

"So if you're a seed and you land under your parent, the probability of you surviving is almost zero."

Forest elephants, however, can take seeds several kilometres from their parent plant.

"It's like the parable from the bible - some seeds will land on stony ground, some on poor soil, but some will land on good soil...

"With lots of elephants roaming the forests, at least some seeds are likely to land in the right place to grow," says Dr Blake.

And a myriad of other species depend on the structure of the forest that the elephants create.

"Insects, mosses, lichens, invertebrates, other vertebrates; a whole gamut of animal, plant and fungal species are specific to certain trees or plants," explains Dr Blake.

"If we lose elephants, we're going to lose those trees; forest biodiversity as a whole is going to diminish."

Professor Lister says that forest elephants are suffering from the same "double whammy" that claimed the woolly mammoths - habitat loss and hunting.

"Today both of those sides of the pinch are caused by humans," he says.

Old piles of elephant dung become fertile grounds for seed germination in the forests

"I think the extinction of the mammoth is a salutary lesson that applies to modern extinctions."

Dr Blake says that time has already run out for the forest elephant.

It could be too late for the lessons we could learn from the mammoth and the mastodon to make a positive difference.

As resource extraction from central Africa becomes more important, more roads and bigger roads will cut through the forests of the Congo basin.

Without effective wildlife management, the elephants will eventually have nowhere left to hide, Dr Blake says.

"We have seen some exciting initiatives like the development of national parks and landscape scale management programmes developed over the last 20 years, but the resources needed to manage these areas properly are pitiful compared to those available for resource extraction."

"I think we've basically blown it."

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Rare lizard saved from extinction

10 June 2011 Last updated at 09:36 By Victoria Gill Science reporter, BBC Nature Flat Island was thought to be the last refuge for these Critically Endangered lizards Scientists from the Durrell Wildlife Conservation Trust have brought 22 Critically Endangered orange-tailed skinks to the UK.

The animals are thought to be extinct on their native Flat Island in Mauritius, because invasive shrews that prey on them are now established there.

This rescue should enable the trust to start a captive breeding programme.

"We ultimately hope to reintroduce the species to the island," said Durrell's head of field programmes, Andrew Terry.

The orange-tailed skink was only discovered on Flat Island, which is the largest of the Mauritian islands, in 1995.

"Before humans turned up in Maritius, the natural world there had a very strong reptile component; reptiles were really driving the ecosystems," Dr Terry told BBC Nature.

The team has brought 22 tiny skinks to Durrell headquarters in Jersey

But human activity has modified this habitat. Many non-native predators, including rats and cats, are now abundant elsewhere in Mauritius. Flat Island was thought to be the last refuge for the tiny orange-tailed skink.

Recent development work on the island, however, which was intended to bring in tourism, brought with it one particularly voracious predator: the Indian musk shrew. This rodent "stowed away" on boats that brought materials and people.

"The secretive skinks were able to hide away from rats and cats, but the shrew is much smaller and was brought in at very high densities and hunts day and night," Dr Cole said.

"Within a year of the discovery of the shrew, we were unable to find any skinks on Flat Island. Unfortunately, they've now gone."

Since the skink was so threatened, Dr Cole and his team had already moved more than 400 of the animals into protected nature reserves on another nearby island. So they were able to capture 22 for transport to Durrell's headquarters in Jersey.

Within a year of the Indian musk shrew's arrival, the skink had disappeared from Flat Island

"Had the reptile team not reacted to the threat of development and the arrival of the shrew, the orange-tailed skink would now be extinct," said Dr Cole.

The rescued skinks will be kept at Durrell, "until we are certain that these translocated populations have established or we manage to find a way to tackle the shrew problem", he said.

The team plan to study the skink, which has never been kept in captivity before, in order to establish a breeding programme.

Dr John Wilkinson from the Amphibian and Reptile Conservation Trust welcomed the project.

"Invasive exotic species, especially predators, are a major contemporary threat to biodiversity," he told BBC Nature.

"Direct action such as the rescue of these skinks is essential to ensure the survival of the species (in) these unique ecosystems. Durrell has a good history of breeding and protecting animals such as this and should do well with the orange-tailed skink."

The team hopes eventually to reintroduce orange-tailed skinks to Flat Island

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Seagrasses face extinction threat

23 May 2011 Last updated at 09:18 By Matt Walker Editor, BBC Nature A manatee grazes on seagrass

Seagrasses around the world are disappearing, with some species now threatened with extinction.

The first global survey of individual seagrass species has found that 14% are at risk of going extinct.

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I was surprised by the level of threat to many species of seagrass”

End Quote Frederick Short Research Professor and Director of SeagrassNet More common species are also in decline, meaning both seagrass habitat and diversity is being lost.

Seagrasses provide food and habitat for a variety of ocean species including manatees, sea turtles and fish such as sea horses.

Seagrasses are flowering plants that grow on the ocean floor.

They form vast meadows that flower and seed underwater, having evolved from land-based plants that entered the water millions of years ago.

Seagrasses alone form important marine habitats.

They act as nurseries for young fish and shellfish, and are the primary food for large marine mammals such as manatees and dugongs, as well as reptiles such as some sea turtles.

They also contribute to the health of coral reefs and mangroves, salt marshes and oyster reefs.

Continue reading the main story 26 of the 72 species of seagrass are declining in number, with 13 increasing. The rest are stable or unknownSeagrasses provide food for dugongs and manatees, animals said to be the basis for the mermaid mythsIt has been known for a while that seagrasses are declining in many parts of the world.

The reasons are many, seagrass expert Frederick Short told the BBC.

Professor Short, of the University of Hampshire in Durham, US is the director of SeagrassNet, an international seagrass monitoring program with 114 sites around the world.

For example, seagrasses are gone from the most developed coastlines due to pollution, said Professor Short.

Seagrasses are in decline in the developing world due to sedimentation, caused by runoff from impacted watersheds and deforestation, and being overloaded with nutrients flowing into the sea from sewage and agricultural runoff.

Seagrasses are also being directly damaged by the dredging of seafloors.

Seagrass is home to a Malagasy cowfish

"But there has never been a review of individual species status," said Professor Short.

So he and an international team of experts convened three workshops to gather all the knowledge about individual seagrasses, and used it to evaluate how at risk each species is. The workshops were hosted by Conservation International, the Global Marine Species Assessment programme and SeagrassNet.

The results are published in the journal Biological Conservation.

"I was surprised by the level of threat to many species of seagrass and to discover that seagrass biodiversity is under greater threat than I believed," he said.

Of the 72 species, his team found that 15 seagrasses should be considered Endangered, Vulnerable or Near Threatened, under criteria laid down by the International Union for Conservation of Nature (IUCN) Red List.

Of those, ten face a significant risk of extinction.

Phyllospadix japonicus is an important habitat-forming grass along the rocky shorelines of China, North and South Korea and Japan. But it has gone from swathes of China's coastline, due to seaweed aquaculture.

Green turtles depend on the green grass

Zostera chilensis is known from only two locations on the coast of Chile, and seems to have already disappeared from one.

Of the 57 remaining species, 48 are considered of Least Concern, while sufficient data doesn't exist to make a judgement on the others.

"Many widespread, common seagrass species which are not presently threatened are nonetheless in decline, so we have both an overall loss of habitat and a loss of biodiversity," said Professor Short.

"Seagrasses are both direct food for important species and as they break down within the coastal ecosystem, they are part of a vast food web that provides food to many organisms within the coastal ocean, including many commercially and recreationally important species.

"Unfortunately, being submerged in the ocean they are rarely directly seen except by swimmers or snorkelers."

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