Monday, July 1, 2013
Schembri.J.(2010) Verdict is still out on Selmunett wall lizard: disagreement on whether subspecies is extinct or not.
The Times July 19th pg.12
The verdict is still out on whether the Selmunett wall lizard is extinct as the planning authority and a naturalist disagree on its status.
The Podarcis filfolensis kieselbachi, as it is known scientifically, is a subspecies of the Maltese wall lizard which lives exclusively on St Paul's islands.
Naturalist Arnold Sciberras, who has been studying the lizard for 13 years, visits St Paul's Islands monthly and says he has not spotted one since 2005.
However, the Malta Environment and Planning Authority will not concede officially that the lizard is extinct because, according to the red list criteria of the International Union for Conservation of Nature, a species is considered extinct "when there is no reasonable doubt that the last individual has died".
Mr Sciberras reacted to Mepa and adamantly said: "I have no reasonable doubt that the Selmunett lizard is extinct in the wild. St Paul's islands are small and it's not like searching an area the size of Malta to find a specimen of a creature."
Although not certain about it, the naturalist believes rats were to blame for the population's decline. Mepa said international herpetological experts, assisting it in field surveys in 2008, were of the opinion that the lizard's decline was attributed to factors other than rats, such as vector-borne diseases, a lack of insect prey due to widespread use of pesticides and "direct persecution and collection of specimens".
Mr Sciberras disagrees: "If vector-borne diseases were the cause of the lizard's disappearance, other subspecies across the Maltese islands would have been affected. As for pesticides being used on St Paul's islands, there hasn't been any agriculture on the island since 1940. I've never seen anyone collecting specimens to keep either," he said.
Mepa undertook a rat eradication project in 2005, making the islands rodent-free by the following year. It said the last sightings its officials made of the lizard were in 2007.
It was not aware of any scientific studies ever conducted on the Selmunett lizard, noting that anyone wanting to conduct a scientific study on St Paul's islands would require a permit.
"What permit? I used to go and observe the lizards, not physically handle them or disturb them. It is legal for anyone to go to St Paul's islands after sunrise, so long as they leave again before sunset," Mr Sciberras said.
A spokesman said Mr Sciberras's admission that he had been carrying out "unauthorised work" on the islands since 1997 came as a "surprise" to Mepa. It did, however, acknowledge that Mr Sciberras had taken part in a scientific study on captive breeding, coordinated by a University professor.
Mepa had "regularised" his position by issuing a permit allowing Mr Sciberras to keep the specimen as part of this project.
Seven specimens were collected by Mr Sciberras in an attempt to increase numbers and kick-start breeding but he abandoned the project in 2006 and returned the lizards to Mepa. Mr Sciberras could not speculate whether three male lizards released by Mepa in June 2007 included some of the ones he previously had in his possession. A female should also have been released at the time but it had died.
Mepa said studies were ongoing, adding that more time had to pass before officially declaring whether the Selmunett lizard is extinct or not.
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