Nineteen percent of the world's reptiles are estimated to be
threatened with extinction, states a paper published today by the Zoological
Society of London (ZSL) in conjunction with experts from the IUCN Species
Survival Commission (SSC).
The study, printed in the journal of Biological
Conservation, is the first of its kind summarising the global conservation
status of reptiles. More than 200 world renowned experts assessed the
extinction risk of 1 500 randomly selected reptiles from across the globe.
Out of the estimated 19% of reptiles threatened with
extinction, 12% classified as Critically Endangered, 41% Endangered and 47%
Three Critically Endangered species were also highlighted as
possibly extinct. One of these, a jungle runner lizard Ameiva vittata, has only
ever been recorded in one part of Bolivia. Levels of threat remain particularly
high in tropical regions, mainly as a result of habitat conversion for
agriculture and logging. With the lizard's habitat virtually destroyed, two
recent searches for the species have been unsuccessful.
Dr. Monika Böhm, lead author on the paper: "Reptiles
are often associated with extreme habitats and tough environmental conditions,
so it is easy to assume that they will be fine in our changing world.
"However, many species are very highly specialised in
terms of habitat use and the climatic conditions they require for day to day
functioning. This makes them particularly sensitive to environmental
changes," Dr. Böhm added.
Extinction risk is not evenly spread throughout this highly
diverse group: freshwater turtles are at particularly high risk, mirroring
greater levels of threat in freshwater biodiversity around the world. Overall,
this study estimated 30% of freshwater reptiles to be close to extinction,
which rises to 50% when considering freshwater turtles alone, as they are also
affected by national and international trade.
Although threat remains lower in terrestrial reptiles, the
often restricted ranges, specific biological and environmental requirements,
and low mobility make them particularly susceptible to human pressures. In
Haiti, six of the nine species of Anolis lizard included in this study have an
elevated risk of extinction, due to extensive deforestation affecting the
Reptiles play vital
Collectively referred to as 'reptiles', snakes, lizards,
amphisbaenians (also known as worm lizards), crocodiles, and tuataras have had
a long and complex evolutionary history, having first appeared on the planet
around 300 million years ago. They play a number of vital roles in the proper
functioning of the world's ecosystems, as predator as well as prey.
Head of ZSL's Indicators and Assessment Unit, Dr Ben Collen
says: "Gaps in knowledge and shortcomings in effective conservation
actions need to be addressed to ensure that reptiles continue to thrive around
the world. These findings provide a shortcut to allow important conservation
decisions to be made as soon as possible and firmly place reptiles on the
"This is a very important step towards assessing the
conservation status of reptiles globally," says Philip Bowles, Coordinator
of the Snake and Lizard Red List Authority of the IUCN Species Survival
Commission. "The findings sound alarm bells about the state of these
species and the growing threats that they face globally. Tackling the
identified threats, which include habitat loss and harvesting, are key
conservation priorities in order to reverse the declines in these reptiles."
The current study provides an indicator to assess
conservation success, tracking trends in extinction risk over time and
humanity's performance with regard to global biodiversity targets.
ZSL and IUCN will continue to work with collaborating
organisations to ensure reptiles are considered in conservation planning
alongside more charismatic mammal species.