Snake aquatic

Aposematically colored, the yellow-bellied sea snake, Pehmis platurus (Hydrophiidae), of the eastern Pacific has venom and is distasteful. It has no known aquatic predators, although remains were found in murray eels and sharks. Predatory fish such as snappers refuse the snake. They reject its meat even when hidden in palatable squid. Predatory fish of the Atlantic ocean, however, ate the sea snake in experiments, and died after 1 of 12 meals (Rubinoff and Kropach, 1970). 

Visual and chemical cues interact in foraging by natricine snakes. Even visual cues alone can elicit prey attack, especially in aquatic foraging (Drummond, 1985). Aposematic color patterns of prey enhance the learning of prey that induces illness. Garter snakes, Thamnophis radix hay deni, were exposed to fish and earthworms presented on black-and-yellow forceps, and then inj ected with lithium chloride (LiCl). Control prey was offered on green forceps. Later, the snakes avoided food from either forceps, but the aversion to prey paired with black-andyellow was stronger (Terrick etal, 1995). 

Terrestrial slugs foUow mucus trails back to their daytime resting areas, to find food, or to mate. They foUow their own, or each other s trails. Slugs can determine the direction of a mucus trail. Predators, such as snakes or aquatic sdomyzid fly larvae, follow the mucus trail to find their prey. Laying the mucus trail is energetically expensive (Cook 1979, 1992 Davies and Blackwell 2007). 

Metamorphosis has also been extensively studied in amphibians, a class of vertebrates which includes frogs, toads, and salamanders. Amphibian means dual (amphi ) life form (-bian) and refers to the typical life history of these animals, in which an aquatic larva metamorphoses into a terrestrial adult. The reptiles, such as turtles, lizards, and snakes, is another class of vertebrates whose species superficially resemble adult amphibians, but do not undergo metamorphosis. 

Cottonmouth Cottonmouth are partly aquatic, living in or near water and feeding mainly on fish and amphibians. These poisonous snakes are usually not aggressive unless agitated or threatened. When angered cotton-mouths will coil their bodies and expose a fully opened mouth as if ready to bite. The... 

Fjeld, R.A., Coates, J.T., Elzerman, A.W., NavratU, J.D., 2002. Mobilities of uranium species in sedimentary interbed from the Snake River Plain. In Merkel, B.J., Planer-Friedrich, B., Wolkersdorfer, C. (Eds.), Uranium in the Aquatic Environment, Proceedings of the International Conference on Uranium Mining and Hydrology III and the International Mine Water Association Symposium, Ereiberg, Germany, 15-21 September 2002. Springer, Berlin, Germany, pp. 293-302. 

I examined three closely related species, two of which (Thamnophis sirtalis and butleri) live in primarily grassy microhabitats (Carpenter, 1952) and one (. proxlmus) which occupies brushy areas in aquatic situations (Clark, 1974). In addition, I examined Regina septemvlttata, another thamno-phiine snake of somewhat confusing taxonomic status (Rossman, 1985) which occurs in habitats quite similar to those in which proximus is found (Branson and Baker, 1974). Differences in the evenness of the terrain of these species preferred habitats should have an effect on both deposition of a trail and the mechanism of orientation to the trail. 

While vision is commonly rated as the dominant sensory mode in reptiles (i.e., Madison, 1977), we believe this is an impression based primarily on work with terrestrial lizards, snakes and tortoises which may not apply as well to the aquatic members of the class. Much more research needs to be done with aquatic and marine snakes and turtles whose habitats provide poor visual, but excellent chemical cueing characteristics. 

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