January 2009 — Copperhead Ratsnake

Our snake of the month is the Copperhead Ratsnake (Elaphe radiata Boie 1827), otherwise known as the Radiated Ratsnake. A fine specimen of this large non-venomous snake, over a meter long, was found this week in one of the artists’ studios.

Copperhead Ratsnake

According to Klaus Dieter-Schulz, who has published a monograph on the Elaphe genus, many snakes of this type are associated with water and swim very well, which has been confirmed with findings of the Copperhead Ratsnake far out to sea. It is thought that this helps them colonise offshore islands, and the snake is well distributed across Asia. Other typical ratsnake habitats include fallow land and scrub edges, interspersed with rubble and larger rocks, like abandoned quarries and refuse disposal sites. Many species of the genus also favour man-made environments, where they prey on newborn and subadult rodents. The Copperhead is sometimes encountered in piles of coconut shells, leading to its local name in Thailand of ‘Coconut Snake’.

When agitated the Copperhead Ratsnake assumes an interesting defence mechanism. It inflates the front half of its body, not width-wise like the cobra, but in height, meanwhile rearing up in an s-shape, in order to appear much bigger than it really is. “They literally dive towards the apparent aggressor with their mouth agape,” Dieter-Schulz writes, “The inflation of the neck causes the often differently coloured interstitial skin to become visible between the scales and the snake immediately assumes a different appearance.” However, if this attack is ineffective, the snake will also play dead, laying limp and motionless on the ground for some time.

Reference:
A monograph of the colubrid snakes of the genus Elaphe Fitzinger, by Klaus-Dieter Schulz, André Entzeroth. Published by Koeltz Sceintific Books, 1996.