Measurement of metabolism of worker ants by using the elimination of caesium-134

In order to find a method for measuring field metabolism of worker ants the elimination of¹³⁴Cs by two ant species has been investigated. Equations relating temperature to radiocaesium elimination and metabolism have been found. From these equations the relationship between elimination and metabolism is calculated. Consequently, the elimination of the isotope can be used for measuring metabolism.A pilot field experiment withLasius alienus (Först.) reveals that the traditional methods of estimating field metabolism give values which are considerably lower than the value based on caesium elimination rate. This difference is supposed to be mainly due to greater motor activity of the animals in the field. Consequently, the value of the caesium elimination methods is closer to the "true" value of field metabolism.