Northern Water Snake
Nerodia sipedon

Family Colubridae

Adults 30" to 53" in length. Color gray, brown, or tan, with darker bands on anterior end of body, changing to dark angular blotches posteriorly. Underside yellowish or gray, with with grey, yellowish, or reddish markings. Moderately heavy body, with keeled scales. Divided anal plate.
Elevation Range:
Below 5500' in eastern Colorado.
Subspecies in Colorado:
Nerodia sipedon sipedon

Listed as Natrix sipedon in older publications.
  Northern Water Snake
Photo by L. Livo and S. Wilcox,
from Hammerson, 1986.
Used with permission.
CountyRef. CountyRef. CountyRef. CountyRef.
Adams *  Dolores  La Plata  Pitkin 
Alamosa  Douglas *  Lake  ProwersH
ArapahoeHMS11 Eagle  LarimerH Pueblo * 
Archuleta  El Paso *  Las Animas *  Rio Blanco 
Baca *  Elbert *  Lincoln *  Rio Grande 
BentH Fremont *  LoganRLh5 Routt 
BoulderH Garfield  Mesa  Saguache 
Chaffee  Gilpin  Mineral  San Juan 
Cheyenne *  Grand  Moffat  San Miguel 
Clear Creek  Gunnison  Montezuma  Sedgwick * 
Conejos  Hinsdale  Montrose  Summit 
Costilla  Huerfano *  MorganH Teller 
Crowley *  Jackson  OteroH Washington * 
Custer *  Jefferson *  Ouray  WeldH
Delta  Kiowa *  Park  YumaH
DenverH Kit Carson *  Phillips * 
Map of Colorado
Color Key
Adams Alamosa Arahapoe Archuleta Baca Bent Boulder Chaffee Cheyenne Clear Creek Conejos Costilla Crowley Custer Delta Denver Dolores Douglas Eagle El Paso Elbert Fremont Garfield Gilpin Grand Gunnison Hinsdale Huerfano Jackson Jefferson Kiowa Kit Carson La Plata Lake Larimer Las Animas Lincoln Logan Mesa Mineral Moffat Montezuma Montrose Morgan Otero Ouray Park Phillips Pitkin Prowers Pueblo Rio Blanco Rio Grande Routt Saguache San Juan San Miguel Sedgewick Summit Teller Washington Weld Yuma