It looks to be hybid of Gulf Salt Marsh N. clarkii clarkii and Broad-Banded Watersnake N. f. confluens. This is a very interesting occurance. According to Conant and Collins (C&C), N. c. clarkii is a resident of salt and brakish water, they are rare in freshwater habitats. Further, N. c. clarkii is known to hybridize with N. fasciata confluens, and the pattern is described as combinations of stripes and blotches.
Normally, clarkii have two dark stripes on either side of their body, offset by two tan or yellowish stripes. In this case part of the lower tan stripe is being invaded by the darker brown. Compare the side photo to Plates 20 and 21 of C&C. The color and striping is a dead ringer for the Gulf Salt, while the shape and width of the partial banding is remarkably similar to the Broad-Banded.
I think you have a natural hybrid of N. c. clarkii X N. f. confluens. You should be able to verify this if you can get a look at the ventral pattern, which is distinctively different. If they are indeed hybrids, then the belly patterns should be a mixture of the two distinct patterns. The patterns are shown on the same Plates in C&C.
Now here is the interesting part!
- Is the water in you pool salty?
- How far are you from the nearest salt or brackish water?
- Where is the house in respect to the landfall of the hurricane?
- Could these be the offspring of snakes relocated by the hurricane?
- That is, could they be the result of a Gulf Salt washed inland that crossbred a Broad-banded?
To answer this question, compare your location to the range maps and see if you are outside the normal range of N. c. clarkii. Then, catch one of those guys and get a pic of its belly to post here. Look around your area and see if you find anymore like your two. If they are all over, then you are in a normal hybrid zone. If not, you may be in a hurricane hybrid zone!
Regards,
John D.
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I am so not lesdysxic!
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