Tasmanian tigers, also called thylacines, were declared extinct in 1986 but that has not stopped a stream of sightings and claims of evidence.
A Tasmanian thylacine researcher, who calls himself the Tigerman, has just published an 80-page book on the Internet where he presents his case that the species exists.
The Tigerman, who is based in rural Tasmania, uses a pseudonym because he says revealing his identity would make his work harder.
In his book - called Magnificent Survivor, Continued Existence of the Tasmanian Tiger - he presents photographs of what he claims are thylacine footprints and possible lairs, tracks, scats and prey kills.
He discusses his two claimed thylacine sightings and theorises on the population, behaviour and psychology of the species, based on his six years of searching.
He says three population groups exist in Tasmania - in the North-East forests, the North-West and the South West World Heritage Area.
"I believe if thylacine numbers in each of these three divisions were any higher, then the animals would not be able to remain hidden within the available habitats of each," he says in the book.
"If the numbers were any lower then it is unlikely the species would have been able to sustain itself to date."
The South-West is defined as the area Strahan to Roseberry, the South West World Heritage Area and eastern perimeter.
The terrain is thickly vegetated and he says this is not ideal for thylacines, which prefer a mix of open country and forest.
But it is undisturbed and is a stronghold for the species.
In the North-East, he says the population lives in the mountainous areas to the north and east of the Ben Lomond massif, in sight of Launceston, with occasional movement as far south as the Buckland military training area. He says the species tries to move south but is often forced back upon encountering human disturbance.
But he says the population is unstable or continuing to decline due to the effects of inbreeding, devil predation and stress from frequent disturbance.
The North-West (Woolnorth to Rocky Cape, Western Tiers, Highland lakes, Cradle Mountain, Rosberry and Strahan) is recognised by many, says the Tigerman, as the best habit for the species but he does not agree with this view.
He says the species is confined to the most isolated tracts of undisturbed central forest.
The Tigerman says if his estimation of the total population is inaccurate, then the actual number would be smaller, not larger and may not be enough to ensure the species' long-term survival.
Although the species is extremely difficult to spot, the Tigerman says he made two sightings in May 2000.
He says one day he was driving fast on a logging track and the speed apparently caught a juvenile thylacine unawares.
"The animal was walking slowly along the track facing me, and I could see that it was quite slender, but still about the height of a medium-sized dog," he said.
"The colour appeared chocolate brown with golden tinges on hair around the edges of the body.
"As I approached at high speed the animal looked up suddenly, then turned, and ran to the side of the track. I clearly saw an unmistakable thylacine shape and loping running style."
The next day he saw a larger thylacine at the some spot, walking across the track about 150m away.
"This second animal was very large, with shape and size similar to a panther; longer in the body than the juvenile seen the day before," he said.
The Tigerman immediately drew diagrams and set up automatic cameras, but could not get a photograph.
The Tigerman also includes in his book a series of photographs from a site he calls "Location X".
The location is a network of sandstone caves in the East Coast forests and his photographs show pictures of dead sheep, which he suspects are thylacine kills.
He says the attacks match the thylacine kill patterns described by trappers and shepherds from the early 1900s.
Paw prints were found in the caves and there were tracks which showed the caves had been visited by large animals which apparently dragged their tails.
He says the prints match the known thylacine print patterns and the prints and tail marks were too big to be made by devils.
A nest was made in one of the caves, consisting of sand pushed up to make a large hollow mound and bedding material (of chewed sticks) placed in the hollow.
He said that wombats made these sorts of nests in tight holes, but this was an open chamber and there were no dog prints at the location.
The Tigerman said this week that he lived in a remote place and publicly revealing his identity would be unhelpful to his work.
"I do not want to get into a discussion about it because there is a level of belief that people who do this (search for thylacines) are kooks," he said.
"I just do not want to be involved in all that, it's a hassle I do not want."
Also, he wanted to stay anonymous because other tiger hunters could try to follow him plus he was concerned that government officials could interfere.
"There is comment in the tiger search community to be very careful of the Government," he said.
He said that a great deal of evidence would have been collected by government officials on thylacine sightings but almost none of this was publicly available.
This was apparently done in the belief that if the species existed, it was best left alone.
But the Tigerman said that he believed the species existed, was in desperate trouble and its only hope was for the secrecy to end.
"Because the world will not protect an animal it thinks is extinct," he said.
He says he has not presented his footrprint casts, scats or other material for analysis by museum staff because it would not be conclusive and he did not trust them, because he detected a patronising attitude to thylacine researchers.
"The time for urgency is now, the thylacine species has never been so low and pressures upon it are growing," he said.
See the book at http:/ /www.users. bigpond.com/ tigerbook/
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