Taken in the last week of March, about a month later than I saw them last year. The markings on the head and neck are unique to each snake, and by comparing photos, I've been able to ID 3 individuals that I've seen in previous years.
As well as the usual males I expect to see at this time of year, there was also a tiny juvenile (the orangey-coloured one) nearby, no more than about 4 inches long.
Dave