Northern water snake The belly also varies in color. It can be white, yellow, or gray. Usually it also has reddish or black crescents. The northern water snake is nonvenomous and harmless to humans, but superficially resembles the venomous cottonmouth and is often killed unnecessarily as a result of this mistaken identity. The two can be easily distinguished by morphological traits: the water snake has a longer, more slender body and a flattened head the same width as the neck, round pupils, and no heat-sensing pits. The cottonmouth has a fatter body, a wedge-shaped head with prominent venom glands that are wider than
Venomous snake humans, including their distribution and behavior. For example, while the inland taipan is regarded as the world's most venomous snake based on LD tests on mice, it is a shy species and rarely strikes, and has not caused any known human fatalities. On the other hand, India's Big Four (Indian cobra, common krait, Russell's viper, and saw-scaled viper), while less venomous than the inland taipan, are found in closer proximity to human settlements and are more confrontational, thus leading to more deaths from snakebite. In addition, some species, such as the black mamba and coastal taipan, occasionally show some aggression,