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Thread: snakes spread by predatory birds?

  1. #1 snakes spread by predatory birds? 
    Time Lord
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    Apr 2008
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    Many snakes give live birth. The young are independent. This makes me wonder if pregnant snakes are sometimes transported by bird (say, to an island) where the mother is devoured, while her offspring disperse.

    It occurred to me because of the ubiquity of live-birthing garter snakes on islands from Washington State, into the Alaskan Panhandle. Often snakes represent the only permanent vertebrate inhabitants. I'm doubtful that even water-loving garter snakes could endure a distance of cold ocean no terrestrial mammal has crossed.



    Here's an observation that suggests the scenario:
    http://si-pddr.si.edu/dspace/bitstre...agle_snake.pdf

    The eagle was pursued by another after picking a large garter snake (meaning female) so it had to fly some distance away, over water.



    Could we say that live birth is advantageous to the spread of a species, given this sort of predation?


    A pong by any other name is still a pong. -williampinn
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  3. #2  
    Forum Radioactive Isotope skeptic's Avatar
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    This is a known method of spreading pest rodents to isolated island bird sanctuaries. No reason it should not apply to snakes as well.

    Of course, if does not matter if the snakes are egg laying, since the predated snake may be pregnant with fertile eggs. The predator may drop the snake, leaving it alive to lay its eggs.


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