Northern Water Snake (Nerodia sipedon) 2009-4-26 WWW3 Bombay Hook NWR, DE

Very variable.
herpnet says:
Generally, they have light brown or reddish markings on a brown or grayish ground color. The markings consist of bands on the neck that become blotches on the back. There are smaller alternating spots on the sides and the ones closest to the ventral scales have a tendency to be red or reddish.
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