Evaluating and minimising social stress in the care of captive bottlenose dolphins (Tursiops aduncus)

Abstract

Stress can increase an organism's susceptibility to disease. Thus, managing stress and its causes are important elements of captive care. Social factors such as changes in group dynamics, competition over resources, and unstable dominance hierarchies are potential stressors for highly social animals such as bottlenose dolphins (Tursiops sp). We present three case studies of mortality and illness in captive bottlenose dolphins and suggest that stress, resulting from social instability and ensuing aggressive interactions, is likely to have played a role in these health consequences. Stress is implicated by blood profiles, loss of appetite, and gastric ulcers, and social problems and instability are evident in the quantitative analysis of individual activity levels and association patterns. This is a unique study on marine mammals in that it demonstrates a correlation between quantitative behavioral indices and physiological measures of stress and health. Recommendations are made for the management of captive dolphins including regular quantitative assessment of behavior and associations and maintenance of appropriate groupings of age and sex classes. Behavioral records can be an important early indicator of health problems and may also serve as a useful tool for recognizing potentially stressful social changes and circumstances. Zoo Biol 21: 5-26, 2002.

Pectoral Fin Contact Between Dolphin Dyads at Zoo Duisburg, with Comparison to Other Dolphin Study Populations

“…These studies have focused on stress (Waples & Gales, 2002); mother-calf interactions (Gubbins et al, 1999) and calf development (Fellner et al, 2012), including the development of whistle (Fripp & Tyack, 2008) and echolocation production (Favaro et al, 2013); and dolphin/human interactions, particularly during interactive programs (Frohoff & Packard, 1995). Studies investigating social, affiliative, and communicative behavior of captive dolphins are scarce (e.g., Tamaki et al, 2006;Dudzinski et al, 2010); and research that compares wild and captive dolphin social behavior are even more uncommon (Caldwell et al, 1965;Brown et al, 1966;Mann & Smuts, 1999;Dudzinski et al, 2010;Greene et al, 2011).…”

An Inventory of Peer-reviewed Articles on Killer Whales (Orcinus orca) with a Comparison to Bottlenose Dolphins (Tursiops truncatus)

“…Leger et al, 2009;physiology: Worthy, Worthy, Yochem, & Dold, 2013;reproduction, Asper, Young, & Walsh, 1988;Robeck et al, 2009). Even research on aspects of cognition and sociality of bottlenose dolphins has been conducted in both wild and captive settings and resulted in information that facilitated more species-appropriate forms of enrichment and social groupings for captive animals (Fabienne & Helen, 2012;Waples & Gales, 2002). Research with killer whales may benefit from similar studies.…”

Effects of an Increase in Group Size on the Social Behavior of a Group of Rough-Toothed Dolphins (Steno bredanensis)

“…sometimes form consistent long-term associations, generally between members of the same sex; for example, males will often form stable alliances with one or two other males in order to sequester and mate with receptive females (Connor et al, , 2000aSmolker et al, 1992;Waples & Gales, 2002;Wells, 2003). Adult females may also form stable associations within nursery groups, both with their calves and with other adult females in the group (Wells, 1991;Mann & Smuts, 1999;Mann et al, 2000).…”

“…Among captive dolphins, the formation of a social hierarchy is especially apparent (Waples & Gales, 2002) and is often established and maintained by agonistic dominance relationships (Samuels & Gifford, 1997). As such, physical contact is not always affiliative, and behaviors such as biting (Norris, 1967;Parsons et al, 2003) and body slamming (Samuels & Gifford, 1997) are more likely aggressive in both captive and wild settings.…”

“…However, it is important to consider the context in which these behaviors occur as oftentimes behaviors that are normally seen as aggressive can also be seen during play bouts (Dudzinski, 1996;Marten et al, 1996;McCowan et al, 2000). Since captive dolphins are restricted in the number of potential alliances they can establish, changes to their group structure could have a drastic effect on their social dynamic (Waples & Gales, 2002).…”