“…However, blood collection can be stressful for the study animal (Pavlova et al, 2018; Small et al, 2017), and handling stress risks artificially elevating measurements of stress hormones. Alternative non-invasive methods based on quantifying glucocorticoid metabolites in droppings, hair, feathers, or saliva have attracted much attention and have been validated for an increasing number of species (Sheriff et al, 2011; Palme, 2019; Dantzer et al, 2010; Hämäläinen, Heistermann, Fenosoa & Kraus, 2014), including Southern pied babblers ( Turdoides bicolor ; Jepsen et al, 2019). Measurement of adrenocortical activity via faecal glucocorticoid metabolites (fGCMs) can eliminate the need for handling of study animals altogether, thereby avoiding artificially increasing the circulating glucocorticoid levels of the study animals (Hodges et al 2010), provided that the collection of droppings is not stressful to the animal.…”