Source: vroegevogels.vara.nl, photo by PuchatechK
A 'herpetoduct' is a tunnel for reptiles. In 2009, RAVON and the province of Gelderland (the Netherlands) designed just such an underpass. Located near Elspeet, it appears well-suited to the various reptile species making use of it.
The tunnel is meant to prevent traffic deaths. It turns out that other kinds of underpasses – those not made especially for reptiles – see only limited reptile use. For this tunnel, however, its designers focused on the most suitable microclimate in the tunnel, and on optimal pathways leading to and from it. The underpass itself is spacious, and its roof is left open where possible. There are corridors at the forest edge, and guiding elements from the heather to the tunnel.

Reptile use of the tunnel was monitored from 2012 to 2014, and the results were very positive. The viviparous lizard and the sand lizard were especially frequent users, though the adder, the slow worm, and even a smooth snake have also been spotted in the herpetoduct.
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