Puncture versus capture: which stresses animals the most?

“The stressed bird in the hand”: Influence of sampling design on the physiological stress response in a free-living songbird

“…We predicted a stronger HPA-axis activation with higher CORT levels in birds that experienced additional handling stress and underwent three sampling procedures. This effect, however, did not become apparent in our study which is supported by findings in other avian and non-avian species (Bonnet et al, 2020; Davis, 2005; Stangel, 1986). Bonnet and colleagues, for example, recently reported, that blood sampling per se did not affect CORT levels in dice snakes ( Natrix tessellata ) (Bonnet et al, 2020).…”

“…short handling procedures and blood sampling within 1% of the body-mass (Fair et al, 2010; Owen, 2011). In this context, several studies suggest that taking multiple blood samples from a healthy animal, has minor effects on its condition, behaviour and survival (Ardern et al, 1994; Bonnet et al, 2020; Davis, 2005; Lubjuhn et al, 1998; Stangel, 1986; Voss et al, 2010). Birds, however, perceive the capture and restraint during blood sampling as a life-threatening situation.…”

“…Given the severity of this acute stress response, the possible effects of the sampling procedure itself (e.g. blood loss) may only marginally affect measurable stress parameters (Bonnet et al, 2020; Davis, 2005; Stangel, 1986; Zylberberg, 2015). Whereas it is well recognised that stressors (i.e.…”

“…For example, Canoine et al (2002), reported higher stress-associated hormone levels (corticosterone; CORT) in birds exposed to a predator in addition to the blood sampling procedure and thereby demonstrated a surprisingly high context-specific plasticity in the stress response. On the contrary, studies which applied different stress indicators, such as the change in total white blood cells (WBC), show that additional handling and blood sampling only has negligible effects (Bonnet et al, 2020; Davis, 2005). A possible explanation for this discrepancy may be that the different physiological stress systems and their measurable endpoints vary in their sensitivity to stressors and the timescale each parameter integrates stress (Gormally and Romero, 2020).…”

The welfare and ethics of research involving wild animals: A primer

“…A handful of studies have compared broad outcomes, such as survival between groups undergoing different procedures (Douglass, Kuenzi, Wilson, & Van Horne, 2000; Wimsatt, O'Shea, Ellison, Pearce, & Price, 2005). However, few studies have compared the stress of specific procedures during handling, for example, the stress of microchipping versus toe‐clipping in lizards (Langkilde & Shine, 2006), or the additive stress of blood sampling after capture in snakes (Bonnet, Billy, & Lakušić, 2020). For most species and handling procedures, the extent that procedures themselves cause additive stress and the duration over which they compromise welfare is unclear.…”