South African Lycaenid
stable isotope studies
To investigate the feeding habits of South African lycaenids, I spent nine months in South Africa collecting data to conduct the first multi-species study of Lepidopteran stable isotope analyses. I surveyed 33 sites and collected over 600 specimens of plants, ants, Hemiptera and butterflies.
I then performed 15N and 13C stable isotope analyses determine the diets of the nearly 150 species of South African lycaenids and conducted controlled feeding trials to determine fractionation levels likely to occur during metabolism and metamorphosis.
My analyses showed that 13C values reflected C3, CAM, C4 and lichen food plants. And 15N values provided a useful index of the spread from herbivorous and insectivorous diets. While neither 13C nor 15N by themselves had enough signal to separate butterflies by herbivorous, insectivorous or lichen feeding diets, when combined they could.
photo by Ada Kaliszewska