The Development of an Operant Conditioning Training Program for New World Primates at the Bronx Zoo

This article describes the development of an operant conditioning training program for 17 species of New World primates at the Bronx Zoo. To apply less invasive techniques to husbandry protocols, the study introduced behaviors-hand feeding, syringe feeding, targeting, scale and crate training, and transponder reading-for formal training to 86 callitrichids and small-bodied cebids housed in […]

Investigation of the sleep electrocorticogram of the common marmoset (Callithrix jacchus) using radiotelemetry

OBJECTIVE: To evaluate the use of a totally implantable radiotelemetry system for recording the sleep electrocorticogram (ECoG) of a small new world primate, the common marmoset (Callithrix jacchus) without restraint during data collection. METHODS: Under anaesthesia a telemetry transmitter, which allowed the recording of a single ECoG channel, was implanted intraperitoneally. This system allowed ECoG […]

Introduction of gum Arabic and guar to the diet of captive black-tufted ear marmosets

Gum plays a significant role in the feeding ecology of wild callitrichids and thus is also supplemented to several primate species in captivity. However, little is known about the feeding habits of black tufted-ear marmosets (including gummivory), in both wild and captive populations. Therefore, the present study introduced gum to the diet of adult captive […]

Mobbing vocalizations as a coping response in the common marmoset

Using a non-invasive method of sampling saliva followed by assay for cortisol levels, we found that common marmosets (Callithrix jacchus) show a decrease in cortisol levels after seeing a snake-model stimulus that reliably elicits mobbing (tsik) calls. In fact, there was a significant positive correlation between the number of tsik vocalizations made and the magnitude […]

Diminished maternal responsiveness during pregnancy in multiparous female common marmosets

Common marmoset monkeys (Callithrix jacchus) live in small groups in which, usually, only a single female breeds and all group members provide infant care. When two females breed concurrently, however, they may commonly kill one another’s infants, especially during the peripartum period. To investigate the mechanisms underlying infanticide by breeding females, we characterized responses of […]

Feeding Gum Arabic to New World Monkeys: Species Differences and Palatability

Members of the New World primate genera Callithrix and Cebuella have specialisations for eating plant exudates. Exudates are also an important component of the diets of many other callitrichid species in the wild, especially at times of nutritional stress. Gum arabic is fed daily to all marmosets and to some tamarins in Jersey Zoo’s collection. […]

The humane control of captive marmoset and tamarin populations

In zoo and laboratory colonies of marmosets and tamarins (Callitrichidae) there has been an increasing need to adopt breeding control methods. In zoos, this need has been driven by a growth in populations. In laboratories, increased interest in control options has followed from the requirement to improve welfare by housing potential breeding animals together. Progestagen-containing […]

The psychology of control: Effects of control over supplementary light on welfare of marmosets

It is often argued that increasing the amount of control that animals have over various aspects of their environment has a positive effect on their welfare, despite limited empirical evidence. We gave 12 pairs of common marmosets (Master pairs) control over supplementary light in their cages (additional to the regular room illumination). The light also […]

Stress and stress reduction in common marmosets

Surprisingly few studies have measured cortisol levels in captive primates using samples collected during everyday life to gauge which activities and circumstances might induce or reduce stress. Much of what is behaviourally identifiable as stress may not to be reflected in physiological stress, or vice versa, leading to the often-erroneous conclusion that the primates are […]

Bimodal Temporal Organization of Specific Vigilance Behaviors in Captive Black Tufted-Ear Marmosets (Callithrix penicillata)

The aerial/terrestrial scan and glance behaviors of 20 captive adult black tufted-ear marmosets (Callithrix penicillata), kept undisturbed in their own familiar social environments, were assessed at 07:00, 09:00, 11:00, 13:00 and 15:00 h, as little is known on the temporal organization of their vigilance repertoire, particularly under normal social and stress-free conditions. For each time […]