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Flora Cordis Johnson wrote:
>We see small snakes flattened on the road here in the summer, but it is
>interesting to me to note that I have never seen a large one killed on the
>road. Perhaps the crows like to eat the bigger ones, thus removing the
>carcasses before I see them, but I prefer to think that the older snakes are
>too smart to bask on the warm asphalt as the small ones do.
>
Hi Flora & All, Aug 20, 2006
This could be just a reflection of attrition (and I expect a
tendency of younger snakes to disperse in search of their own homestead).
To get some idea of possible age and size distributions, that might
result from constant mortality and constant growth rates, I made some
(perhaps wildly incorrect) assumptions--
1) A snake half life of 1 year,
2) A birth length of 15 cm.,
3) A length at each birthday of 1.21 times previous,
4) Production by each pair of 4 young per year, starting in year 2.
In this model, which after young are born leads to a stable
population of 2000 snakes, only one snake out of this total total
reaches a length of 101 cm at age 11 and 97% are less than 32 cm long.
Yt, Dw, Kentville
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