The work covered by this proposal includes a study of individual monarch butterflies reared in captivity, then used in a mark- release-recapture experiment to determine rates of female mating, spermatophore (a large nutrient mass transferred from male to female) masses from wild males, and body condition and weight change under natural conditions. Nitrogen levels in spermatophores from released and captive males will be measured to determine how protein content changes with male age and mating history. The rate at which spermatophores are digested by females will also be determined. The effects of the nutrients contained in spermatophores will be studied by comparing fertility in females that have received spermatophores of different masses.
