Does positive reinforcement training affect the behaviour and welfare of zoo animals? The case of the ring-tailed lemur ( Lemur catta )

Abstract

Positive reinforcement training (PRT) is an established tool to facilitate animal husbandry, care and research in modern zoos, with potential positive implications for captive animal welfare. The study explored the role of an isolation PRT training programme on the well-being of ring-tailed lemurs (Lemur catta). Eleven subjects were observed during an isolation training protocol to induce the animals to enter an area (training area) calmly and retrieve rewards separated from group members. Duration of individual and social behaviours were collected over two different periods: the baseline period, before the beginning of the isolation training protocol and the training period, in which the collection of the data started at the end of the isolation training sessions. Additionally, behavioural data within the isolation training sessions (latency to enter the training area and retrieve the reward, display of stress-related behaviours) were recorded. Outside the training sessions, lemurs were out of sight significantly more in the baseline (Mean ± SD: 15.46 ± 5.20) than in the training (Mean ± SD: 4.36 ± 2.89) period. Social behaviour was performed significantly more in the training (Mean ± SD: 31.80 ± 12.34) than in the baseline (Mean ± SD: 12.52 ± 5.14) period; particularly, lemurs were in social contact significantly more in the training (Mean ± SD: 14.09 ± 6.00) than in the baseline period (Mean ± SD: 4.58 ± 2.73). Agonistic behaviours were performed significantly more in the baseline (Mean ± SD: 0.23 ± 0.15) than in the training (Mean ± SD: 0.07 ± 0.07) period. Within the training sessions, all the individuals entered the training area, were isolated from conspecifics, and retrieved the reward in 6 out of 9 sessions. Our findings show that, during the PRT period, lemurs displayed their natural behaviour in their everyday social life with significant increase of their affiliative behaviours and decrease of aggressive behaviours with benefits for their welfare status. Thus, lemurs were able to cope with the use of PRT to isolate each individual from its social group − a situation which, without training, might be very stressful. In conclusion, PRT may play a crucial role for the captive management of ring-tailed lemurs in captive facilities, including zoos

Gum feeder as environmental enrichment for zoo marmosets and tamarins

“…The presence of the gum feeder also led to a significant decrease in self-directed behaviors, which have been described as potential behavioral indicators of stress and anxiety in nonhuman primates, at least in some situations (Leeds & Lukas, 2018;Maestripieri et al, 1992). As our results underlined a decrease in the performance of these behaviors, the presence of the gum feeder seems to positively impact the behavior of the study monkeys (Leeds & Lukas, 2018;Spiezio et al, 2017). However, the study monkeys spent a relatively low amount of time performing self-directed behaviors in both the baseline and the gum-feeder periods (4% and 3% of the total observation time, respectively) suggesting that this statistically significant change may not necessarily be biologically important.…”

“…To assess the effect of the feeder on the behavior of the red‐handed tamarins, we created the category stress‐related behaviors (SRB), including coprophagy and self‐directed behaviors. Although these behaviors are found in wild animals and maybe adaptive, they both have been related to stressful and conflict situations within controlled environments (Lutz, 2014; Lutz, 2018; Prates & Bicca‐Marques, 2005; Spiezio et al, 2017; Troisi, 2002; Troisi & Schino, 1987). The gum‐eating behavior was included in the category “feeding/foraging” as in the first‐period gum arabic was provided in bowls with other food; however, to compare the time spent feeding on gum between marmosets and tamarins, the duration of gum feeding from the new feeder was also collected (Table 2).…”

“…Moreover, self‐directed behaviors, such as self‐grooming and scratching, are usually benign activities that occur commonly in nonhuman primates (Maestripieri, Schino, Aureli, & Troisi, 1992). However, in certain situations such as social tension and conflicting or frustrating contexts, self‐directed behaviors can be associated with uncertainty and anxiety and have been considered as displacement activities (Lutz, 2014; Spiezio, Vaglio, Scala, & Regaiolli, 2017; Troisi, 2002; Troisi & Schino, 1987). Thus, a decrease in self‐directed behaviors might be considered as a positive welfare indicator, although these activities are normally included and well‐represented in the species‐specific behavioral repertoire of primate species (Leeds & Lukas, 2018; Spiezio et al, 2017).…”

“…However, in certain situations such as social tension and conflicting or frustrating contexts, self‐directed behaviors can be associated with uncertainty and anxiety and have been considered as displacement activities (Lutz, 2014; Spiezio, Vaglio, Scala, & Regaiolli, 2017; Troisi, 2002; Troisi & Schino, 1987). Thus, a decrease in self‐directed behaviors might be considered as a positive welfare indicator, although these activities are normally included and well‐represented in the species‐specific behavioral repertoire of primate species (Leeds & Lukas, 2018; Spiezio et al, 2017). Similarly, coprophagy occurs in both captive and wild nonhuman primates and may have an adaptive value in these species; however, in controlled environment, this behavior has been related to factors such as nutritional deficiency and medical problems but also boredom and social stress (Krief, Jamart, & Hladik, 2004; Prates & Bicca‐Marques, 2005).…”

Investigating individual and social behaviour of the Northern bald ibis (Geronticus eremita): behavioural variety and welfare

“…We also recorded the time ibises spent out of sight, as if performed in excess this could be informative on the animal state. Indeed, being out of sight is particularly relevant in a zoo environment, as wild animals can sometimes try to hide in the presence of visitors, whenever they are perceived as negative stimuli ( Carlstead, Brown & Strawn, 1993 ; Sellinger & Ha, 2005 ; Davey, 2006 ; Morgan & Tromborg, 2007 ; Hosey, Melfi & Pankhurst, 2013 ; Spiezio et al, 2017 ). For this reason, recording the time spent out of sight has become important and exhaustive to assess the effect of zoo visitors on the behaviour and welfare of the animals ( Farrand, 2007 ).…”