Guys, as many of you know, I've always believed that snakes aren't social... they are just found hanging around together because it happens to be a good spot for whatever reason (ideal temp, availability of food etc). I may have to change my views.
The following was written by a British Herpetologist of some standing, he has worked with British reptiles all his life... and he's pretty old now!)

I am getting toward the end of writing my adder book. The task has brought back quite few memories as I have sorted throught my records and data. Here is something interesting. In 1988 I started doing photographic IDs for both adders and smooth snakes; this in addition to ventral scale clipping. Each season I would photo ID between 4-6 litters of adders. In 1989 I Photo IDd two litters from *******. From this litter I have since recorded two females plus one male. Now, the interesting bit. These two females (sisters) are always together. They both bred for their first time at 7yrs. Since then, their breeding cycles have differed. But, even during the non-breeding years of one they are still seen together. If they both have a non-breeding year I have found them together in the summer grounds.
I cannot really explain this 'bond' but maybe it happens more often than we know. Communal behaviour of gravid females is not unusual.
Oh yes, mom is still alive, well in 2004.
I last saw the sisters in 2004, the photo was taken with my film camera in 2001.





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TP

I have spoken to him since he posted this, to get confirmation, and he has seen these two sisters together every single year during that 15 year period! Serious food for thought, I'm sure you'll agree.