Adrenal activity in maned wolves is higher on farmlands and park boundaries than within protected areas

Long-term quantification of faecal glucocorticoid metabolite concentrations reveals that Mexican grey wolves may habituate to captivity

“…Nevertheless, in the present study, wolves in the non-reproductive season showed two-fold higher levels of fGC compared to the reproductive season. These results are consistent with the work of Spercoski et al (2012) on maned wolves living on farmlands, where home range varied between the two reproductive periods. In our opinion, these conflicting results may be explained at least partially by the composition of the wolf packs at the different zoos and parks in the present study including singletons, iso-pairs and just one breeding couple, which may have biased the effect of the reproductive season on fGC levels.…”

“…These findings are in keeping with a previous study by Touma et al (2003), who observed that male mice (Mus musculus Linnaeus, 1758) excreted higher amounts of faecal corticosteroid metabolites than their female counterparts did. However, most studies have not found gender differences in stress levels, including Pifarre (2004), Creel et al (2002), Sands and Creel (2004), Pifarré et al (2012), and Molnar et al (2015) in wolves, and Vynne et al (2014) and Spercoski et al (2012) in free-ranging maned wolves. Palme et al (2005), on the other hand, reported that sex plays an important role in the metabolism and excretion of faecal glucocorticoids, and this might be the reason why we observed gender differences regardless of the breeding season.…”

“…Bryan et al (2015) recently showed that the disrupted social structure caused by hunting causes physiological stress with elevated levels of cortisol in free-ranging wolves, although some studies have discussed the possibility that stress and aggression levels are higher in captivity than in the wild (e.g. Spercoski et al 2012). In addition, the extracted hormones from faeces sampled by Creel et al (2002) and Sands and Creel (2004) were different from the one used in this study.…”

“…Wolves are highly social, and captive wolves typically maintain a stricter hierarchy within the pack than wild wolves do (Frank & Frank 1982), which is enforced with more frequent intraspecific aggression and dominance displays (Zimen 1976). Spercoski et al (2012) discussed the possibility that stress and aggression levels are higher in captivity than in the wild.…”

“…In addition to confinement, there are temporal pattern-, breeding season-, social rank-, sex-and age-mediated cortisol differences. Romero (2002) explains the seasonal modulations of glucocorticoid concentrations in many species; in maned wolf Chrysocyon brachyursus (Illeger, 1811), Spercoski et al (2012) observed two-fold higher levels during spring compared to the other seasons; however, in timber wolves no seasonal variation has been found in glucocorticoid concentrations (McLeod et al 1996). In wild populations of wolves, Eggermann et al (2013) and Sands and Creel (2004) reported an increase of faecal glucocorticoid (fGC) during the annual mating season.…”