Affiliative and Aggressive Behavior in a Group of Female Somali Wild Ass (Equus africanus somalicus)

Abstract

We observed a group of three young female Somali wild asses to develop an ethogram of social behavior in the first phase of a longer term study of social, sexual, and maternal/infant behavior. The most unexpected finding was the frequency and extent of aggressive interactions, which included Charge, Drive, Neck Wrestle, Head Butt, and Body Slam, behaviors previously reported only for males of other equid species. The overall frequency of aggressive behavior was higher than that of affiliative behavior (84±16.5 vs. 32±5.5, P=0.03), yet no injuries occurred. The dyadic directionality of aggressive behavior suggested a dominance hierarchy, a feature not previously reported for either wild ass or domestic donkeys. The aggression observed may be an accurate representation of the behavior of this species, or their relatively young ages, or their recent transfer from their natal group through quarantine and into a new enclosure may have heightened agonistic tendencies. Further studies will determine whether with time their aggressive behavior becomes more intense or dissipates with maturity.

The effect of fluphenazine decanoate on glucocorticoid production, reproductive cyclicity, and the behavioral stress response in the Persian onager (Equus hemionus onager)

“…LANs have reduced the behavioral stress response in other species, including increased inactivity and approachability (Diverio et al, 1996) and reduced pacing and escape-related behaviors in red deer (Read et al, 2000), increased recumbent time in Mohor gazelle (Gonz alez et al, 2008), and decreased flight distance in Pyrenean chamois (Rupicapra pyrenaica; Marco et al, 2013). Although onagers exhibited higher rates of aggression than reported in domestic horse-mares with foals (12.61 counts/hr Weeks et al, 2000), rates were lower than zoo-housed Somali wild asses (84 AE 16.5 counts/hr; Asa et al, 2012). Abnormal behaviors were noted only 0.7% of the time in our study, comparable to 0.0% of the time that Przewalski's horse mares were reported pacing under a variety of normal zoological conditions (Boyd, 1988).…”

Behavioural and Glucocorticoid Responses of a Captive Group of Spider Monkeys to Short-Term Variation in Food Presentation

“…Although no studies have directly compared feeding competition between wild and captive individuals of a species, there is evidence that the frequency of aggressive interactions is higher among captive than among wild individuals (e.g. Somali wild asses, Equus africanus somalicus [Asa et al, 2012]; eastern grey kangaroos, Macropus giganteus [Höhn et al, 2000]). In this context, decisions concerning the presentation of food will affect feeding competition and may be critical for the well-being of social species maintained in captivity [Young, 1997;Kawata, 2008].…”