Sir David Attenborough, despite highlighting the plight of the remaining 300 mountain gorillas, has decided to omit the apes, of which there are just 300, from a list of endangered animals he would most like to save from extinction.
He's chosen to move away from the well-documented threats to pandas, and tigers. He's decided to create is own Sir David's personal Ark for threatened species, (SMH) of some of the lesser-known fascinating species going down the extinction trail – just like the Dodo discovered by Portuguese sailor in Mauritius in 1598. It was a strange looking bird that had no predators, and wasn't afraid of humans. It was eaten, its eggs attacked by pigs, dogs and cats, and they were wiped off the Earth 80 years after their discovery.
The sailors called the bird the "dodo" from the Portuguese "doudou," meaning "simpleton." Without defences, to was doomed in evolutionary terms as it had no survival skills against marauding humans.
(an image of the ill-fated Dodo)
Sir David said: ''There are a lot of animals today that face the same fate as the dodo. I've been asked to select 10 species I would take me with me on my own personal ark". His selection is not the famous flagship species of mega fauna we all know about. He's chosen some more humble, fascinating but lesser known species.
Sir David chose the animals for a BBC wildlife special, Attenborough's Ark.
His top 10 includes Darwin’s frog - the only frog in the world where the male gives birth to its young. There is also the olm - a salamander that can live to a hundred.
Included in his top 10 is the northern quoll, a small, mouse-like marsupial from Australia. In the past 10 years the population has fallen by more than 50 per cent, mainly because of the introduction of cane toads. The smallest is the Northern measuring around 12 to 30 centimetres and weighing up to 0.9 kilogram for the males.
(The Northern Quoll - of the same family as the Tasmanian Devil).
They eat mainly insects, birds, frogs, lizards, snakes, small mammals and fruit. They will also eat carrion (dead animals).
Australia's record for animal extinction gives us the unenviable reputation of being the per-capita king of wiping out species in a relatively short time since European settlement.
The quickest and simplest way of wiping out a species is occupying its land. It wasn't humans who occupied the land and drove various wallabies, reptiles and bird species to extinction, it was our livestock. Rabbits, foxes, cats, dogs, other invading herbivores and cane toad have taken their toll, but the real source is livestock.
A study in 2003 showed that “ range overlap with sheep is the strongest and most consistent predictor of decline, supports previous hypotheses that cite habitat degradation by sheep as a major ultimate threat ..” “One extrinsic variable—geographical range overlap with sheep—was the only consistent predictor of declines”.
Rabbits invaded while sheep numbers were near an all-time peak in the 1890s, then foxes invaded, coinciding with the period of greatest mammal losses .
Australia's sheep population is now about 70 million, but back in 1990 it was 170 million. Even before 1900, sheep were eliminating species as they spread out across the continent. By 1895, the Australian yearbook records 90 million sheep and 11 million cattle.
Many mammal species are in sharp decline across the north, even in extensive natural areas managed primarily for conservation.
The northern quoll is just one small mammal that in recent decades has been disappearing from many parts of northern Australia, even from Kakadu, a World Heritage listed conservation reserve. Once the quoll was one of the most common small animals in the park.
It appears the arrival of the cane toad in Kakadu was the tipping point for a population already in decline. The quoll's brief life cycle made them particularly vulnerable.
Many are listed as vulnerable or endangered under threatened species laws in the Territory, Queensland, Western Australia, and under federal law. Examples include Northern Quoll, Carpentarian Rock Rat, Golden Bandicoot, Northern Hopping-mouse, and Butler’s Dunnart.
Scientists consider the major threats to these mammals are wildfires, cane toads, damage to habitats by cattle and feral herbivores, being eaten by feral cats, and disease.
The cane toad was released first in the cane fields on the mid Queensland coast, then spread west and further north into Queensland. Most experts agree that the cane toad reached the Northern Territory and Western Australia more recently.
Cattle also change the species distribution by eating what they like best, leaving unpalatable plants behind, which soon dominate the landscape. Large areas are badly eroded and it's impossible to overlook the weed problem. Much of the viable habitat targeted for Northern Quoll within the project area had been degraded due to cattle grazing and the introduction of invasive flora and fauna pest species such as Buffel Grass (Cenchrus ciliaris) and the Common House Mouse.
The cattle industry has driven much of the economic development of Northern Australia.
Some pastoralists have also introduced and spread super grasses, mostly from Africa, that grow far larger than the already impressive native grasses of northern Australia.
These “pasture grasses”, such as Gamba Grass and Mission Grass, may be highly invasive, and – because of their greater bulk and often later seasonal drying – fuel fires that may be at least five to ten times more intense, and hence destructive, than fires fuelled by native grasses.
(Rossiter, N.A., et al. (2003) Diversity and Distributions 9, 169-176. )
Research from African and North American savannas has shown that small mammal abundance and species richness is reduced in the presence of large herbivores. In addition, studies of responses to livestock grazing in Australian arid zones have also demonstrated an impact on small mammals.
Many properties in northern Australia are being developed to increase their carrying capacity – ie, to increase the number of cattle that can be grazed.
Cattle grazing began in the rangelands of Queensland in the 1850s, extended westwards and reached the Kimberley by the early 1900s. It is now the major land-use in northern Australia (68% of the total area), with over 90% of some grassland types grazed by cattle. Over time, trampling and grazing by cattle (and donkeys, horses, buffalo and pigs) reduce the diversity of the grass and shrub layers so that annual and unpalatable grasses proliferate to the detriment of perennial and palatable grasses.
The list of nationally threatened species continues to grow in Australia, with 426 animal species (including presumed extinctions) and 1,339 plant species listed as threatened under the EPBC Act.
A nation, a continent, devoid of diversity, overwhelmed by livestock, introduced flora for fodder, monocultures of crops and livestock, denuded of our natural heritage and indigenous species will be a great cost of “economic growth”.
The fate of the trusting dodo is the pattern world-wide for the loss of species. We have learnt to adapt the environment to our own needs, but it will be impoverished without the planet's fascinating diversity.
Sir David: “The dangers facing the earth’s ecosystems are well known and the subject of great concern at all levels. Climate change is high on the list. But there is an underlying and associated cause — population growth.”