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    Author(s): Dale M. Becker; Carolyn Hull Sieg
    Date: 1987
    Source: Canadian Field-Naturalist. 101(3): 369-372.
    Publication Series: Scientific Journal (JRNL)
    Station: Rocky Mountain Research Station
    PDF: View PDF  (196.49 KB)


    Eggshell weight and thickness indices of Richardson’s Merlin (Falco columbarius richardsonii) eggs collected in southeastern Montana were significantly (p < 0.01) lower than pre-1946 samples. Montana eggshells showed reductions of 13% in shell weight and 20% in shell thickness indices when compared to eggshells collected before 1946. The decreased eggshell weights and thickness indices and the occurrence of 7 organochlorine compounds in Merlin eggs recently collected in southeastern Montana indicates that this raptor population merits periodic monitoring.

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    Becker, Dale M.; Sieg, Carolyn Hull. 1987. Eggshell quality and organochlorine residues in eggs of merlins, Falco columbarius, in southeastern Montana. Canadian Field-Naturalist. 101(3): 369-372.


    0rganochlorines, Merlin, Falco columbarius, pesticides, Montana

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