Validation and use of 22Na turnover to measure food intake in free-ranging lizards

Kerri J. Gallagher*, David A. Morrison, Richard Shine, Gordon C. Grigg

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

7 Citations (Scopus)


As the food intake of free-ranging animals has proved to be difficult to measure by traditional means, the feasibility of using radioactive Na to measure food consumption in a small scincid lizard (Lampropholis guichenoti) was assessed. This technique has previously been used only for several species of mammal. A significant relationship between food intake and Na turnover was found in the laboratory, with Na turnover underestimating intake by 7.6%. The food intake of free-ranging members of a field population was estimated by 22Na turnover to be 9.55, 0.65, 9.39 and 13.75 mg dry weight (day)-1 during autumn, winter, spring and summer respectively. Estimates of assimilated and expended energy from these food intake values agree closely with data reported for other lizards using alternative techniques. This study also describes the technical innovations which were necessary to study lizards weighing less than 1 g; and it suggests that 22Na can provide an easy, reliable and inexpensive means of studying the energetics of many free-living animals.

Original languageEnglish
Pages (from-to)76-82
Number of pages7
Issue number1
Publication statusPublished - 1 Oct 1983
Externally publishedYes


Dive into the research topics of 'Validation and use of <sup>22</sup>Na turnover to measure food intake in free-ranging lizards'. Together they form a unique fingerprint.

Cite this