Aquatic Snake Research

The Water Mocassin or Cottonmouth (Agkistrodon leucostoma) is the only North American pit-viper that is semiaquatic.

The Queen Snake, Regina septemvittata, is one of the most aquatic North American natricid snakes.

Oceans cover 71% of the earth’s surface with a minimum of 356,000 km of coastline, yet only 2.5% (about 86 species) of the 3364 extant snakes are known to inhabit the oceans on a regular basis. It is unclear whether most of these snakes are spending substantial amounts of time in salt water and are well adapted for life in saline waters, or whether they use behavioral osmoregulation, shuttling between marine and freshwater environments while remaining dependent upon sources of freshwater. Given the low percentage of snake species in the oceans, the physical environment appears to provide challenges for snakes. A survey of lifestyles (habitat use foraging modeþdaily activity pattern þreproductive mode) of 2552 alethenophidian snakes in 459 genera revealed about 362 (14%) species using aquatic environments to varying degrees; only 70 (2.7%) of these are sea snakes (Hydrophiinae and Laticaudinae). Another 65 or more species appear to use brackish water or the ocean. The ancient Acrochordidae contains three extant species, all of which have populations in brackish, marine, and freshwater environments. The Homalopsidae containing terrestrial, semi-aquatic, and aquatic snakes has about 14 species that have invaded brackish and marine waters. The speciose Dipsadidae of the western hemisphere has at least seven species with coastal–marine populations, the cosmopolitan Natricidae has about 24 species with populations using brackish waters but most of these also have populations that primarily inhabit freshwater. The semi-aquatic, African Grayiinae has at least one species that uses brackish water. However, any aquatic or semi-aquatic snake with a coastal population is likely to visit brackish water on occasion. Flooding may move snakes downstream into estuaries, while storm surges, high tides, and rising sea levels (prehistoric marine incursions) may move saline water inland.

RSS Serpent Research

  • Cobras - Cytotoxicity as a Defensive Innovation and Its Co-Evolution with Hooding, Aposematic Marking, and Spitting March 15, 2017
    Bryan Frye and a cobra.A University of Queensland-led international study has revealed how one of the world's most feared types of snakes -- cobras -- developed their potent venom.Associate Professor Bryan Fry of UQ's School of Biological Sciences said cobras were killers in Africa and Asia, and caused crippling social and economic burdens through the […]
  • Hypsiboas punctatus, the first fluorescent frog March 13, 2017
    Before and after. The polka-dot tree frog in natural light (top) and under UV (bottom.)Photo credit: Julian Faivovich & Carlos Taboada The first fluorescent frogs have been discovered in South America. The green fluorescence is due to a compound found in the lymph and skin glands of the polka-dot treefrog (Hypsiboas punctatus). At twilight, the phenomenon enhances the frogs’ […]
  • A new homalopsid snake from Myanmar March 11, 2017
    Gyiophis salweenensis Photo credit. Evan QuahThe 54th species of homalopid snake has been described by Quah et al. (2017). The new species, Gyiophis salweenensis was described from the lowlands of Mawlamyine District in Mon state, southeastern Myanmar. The authors suggest that Gyiophis salweenensis  is presumed to be closely related to G. maculosa Blanford and G. […]