Are alpacas especially protective of lambs? An insight into alpaca guardian behaviour towards sheep using an arena preference test

Abstract

Alpacas are increasingly used as a guardian species in Australian sheep flocks in an effort to improve lamb survival rates. Yet little is documented about the role and mechanisms of alpaca guarding behaviours within this environment. The first phase of this study, evaluated the temperament of 44 alpacas by assessing their behaviour when individuals were separated from herd mates. Tests included agitation while in an isolation enclosure, flight speed and behaviour in observation arena tests. The second phase of the study evaluated alpaca responses to different auditory, olfactory and visual cues representative of young lambs, adult sheep (ewes) and other novel stimuli. Alpacas (n = 24) which had not previously been exposed to sheep were individually presented with stimuli in a test arena. Behavioural responses were recorded over 2 min and analysed to compare differences between stimuli type (lamb/ewe/other) and stimuli cue form (live animal/auditory only/olfactory only/visual only). In phase one of this study alpacas exhibited little agitation while retained in an isolation enclosure with 67% of animals demonstrating a low agitation score. Females appeared to have a more ‘reactive’ temperament than males, exhibiting significantly faster flight speeds (P < 0.01) and more frequent pacing behaviour (P < 0.01) in the observational pen. In the arena test both male (n = 12) and female (n = 12) alpacas consistently exhibited greater attraction towards the lamb stimuli type (for all cue forms) compared to the ewe and other atypical stimuli (P < 0.05 for all comparisons). Alpacas showed the greatest attraction towards the live lamb compared to visual (P < 0.01), auditory (P < 0.01) and olfactory lamb cues (P < 0.001). Both male and female alpacas demonstrated similar response times and there were no significant differences between alpaca sex in the total time spent reacting to the lamb and ewe stimuli. This study demonstrates that alpacas exhibit a greater attraction towards or interest in young vulnerable animals such as lambs and supports the available anecdotal evidence that the use of alpacas as livestock guardians may be useful in improving lamb survival rates.