Tenerife Lizard |
Reptiles of various species are usually good at colonising
islands, and the Canaries are home to a diverse range of endemic lizards. There
are no native snakes, and at present no native land tortoises, although fossil;
ones are known. It is probable that in the past various species of sea turtles
also nested, but today they are only seen at sea. The most common of these is
the Loggerhead Turtle, Caretta caretta, which also breeds in the Mediterranean.
There are even a few reports of Leatherback Turtles beaching on some of the
eastern islands, but no proof of nesting or nesting attempts.
Stripeless Tree Frog |
Having been surrounded by salt water their entire history
there of course no native amphibians on the islands. People have changed this
though, with introduced populations of water frogs Rana perezi in some areas
and more widespread Stripeless Tree Frogs Hyla meridionalis (the latter are
common around banana plantations). Given how uncommon natural open water bodies
are on the islands these amphibians are unlikely to spread away from human
modified areas.
Gran Canaria skink |
Chalcides skinks are a widespread group with three species
known from the various islands. As they are burrowing animals the casual
visitor is unlikely to see one.
Boetger's Wall Gecko |
Geckos are extremely good at colonising islands and the
various islands in the Canaries are home to four species of Tarentola wall
geckos. There is usually only one species per island, but today they also face
competition from the widespread House Gecko Hemidactylus turcicus. This last
tends to stay near human habitations at present though.
El Hiero Giant Lizard |
The most distinctive of the endemic lizards are the nine
species of Gallotia, mostly small to medium sized lizards which in behaviour
resemble the common Podarcis wall lizards that can be seen around the
Mediterranean. This genus is endemic to the islands, and is most closely
related to the Psammodromus lizards found in northern Africa and south west
Europe. The Gallotia species can be divided into two main groups, a basal group
of mostly small (except for G. stehlini on Gran Canaria) species which are
mostly insectivorous, and a group on the western islands which include both
small insectivorous species and very large, omnivorous or herbivorous species.
The largest of the giant forms, G.goliath from Tenerife, reached as much as 1m
long and is now sadly extinct. Many of the other giant lizards were believed to
be extinct as well, but in recent years a few relict populations have been
discovered and are the subject of intensive conservation efforts. The survivors
are all much smaller than their ancestors, probably a result of heavy predation
on larger individuals by the feral cats the islands small with, and also the
restricted food supply in their last refuges. These are mostly off shore
islands or steep cliffs in remote areas, and constitute another threat – an
avalanche or severe storm could easily wipe out the remaining wild populations.
In recent years another threat has arisen on Gran Canaria,
the only island where large Gallotia lizards are reasonably widespread. These
are G.stehlini, and at least at present are listed as Least Concern by the
IUCN. Unfortunately released pet Californian Kingsnakes Lampropeltis
californiae are now breeding in the wild, and as these are reptile predators in
the wild they pose a grave risk to the native lizards.Details of species shown:
Stripeless Tree Frog Hyla meridionalis (from Wikipedia)
Boetgers Wall Gecko Tarentola boetgeri (Gran Canaria) (from Wikipedia)
Gran Canaria Skink Chalcides sexlineatus (from Wikipedia)El Hiero Giant Lizard Gallotia simonyi (from Wikipedia)
Tenerife Lizard Gallotia galloti (own photo)
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