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

Abstract

Tactile exchanges using the pectoral fin have been noted in a variety of dolphin species. In this study, bottlenose dolphins (Tursiops truncatus) at Zoo Duisburg in Germany were seen to exchange pectoral fin contact much like both wild and captive dolphins. The rate of overall contact (touches and rubs) was slightly larger among the Zoo Duisburg dolphins than for three other study sites, although relative rates for contact via rubs and touches by Zoo Duisburg dolphins appears similar to that of dolphins at the other study sites. Pectoral fin contact between Zoo Duisburg dolphins was more similar to that of dolphins at the Roatan Institute for Marine Sciences in that there was no difference in whether the dolphin was rubber or rubbee when initiating pectoral fin contact, although at all sites, including Zoo Duisburg, the rubber was more often the initiator of a pectoral fin contact. More similar to both wild groups, but not the other captive group of dolphins, Zoo Duisburg dolphins had a strong preference for the horizontal body posture when exchanging pectoral fin contacts. The most striking result is that all dolphins studied have a strong preference for body part contacted: when the rubbee is initiator, the top three body parts most contacted by all dolphins include the face, rostrum, and side. Similarly, when in the role of rubber initiator, the top most contacted and third most contacted body parts are identical at all four study sites. The exchange of contact via the pectoral fin seems to be a conserved action with respect to form and function across dolphin species regardless of the environment in which the dolphins reside.

Evidence for Maternal Style Among Adult Female Dolphins When Sharing Pectoral Fin Contacts with Their Calves

“…Because this paper extends our examination of PFC exchanges specifically to mother/calf dyads, our definitions for several terms (e.g., body parts, postures) were consistent with previously published work (e.g., Dudzinski et al, 2009Dudzinski et al, , 2010Dudzinski et al, , 2012Dudzinski et al, , 2013. Kin relations were assessed based on maternal relatedness; paternity was being assessed via DNA sampling but was not complete for all dolphins in this study group and, thus, paternity was not used to define kin relations.…”

“…Our previous research on pectoral fin contacts (PFC) exchanged between dolphins established that PFC is exchanged at similar overall rates and within same-aged and sexed dyads than mixed-aged and sex pairs regardless of environmental setting (Dudzinski et al, 2009(Dudzinski et al, , 2010(Dudzinski et al, , 2013. We also found PFC is a tool to establish and maintain social bonds between non-kin male bottlenose dolphins .…”

“…To address these research questions, we examined the following variables from a 16-year archive of video data collected using a focal follow sample protocol with all occurrence documentation of dolphin interactions and behavior, and event sampling of pectoral fin contacts (PFC) exchanged between two individuals from all video data. Previous research focused on PFC exchanges between dolphins in different settings (Dudzinski et al, 2009(Dudzinski et al, , 2010(Dudzinski et al, , 2013, PFC exchanges as compared with self-contact by individual dolphins (Dudzinski et al, 2012), and PFC as a tool for social bonding between non-kin ; mother/calf pairs and sibling pairs are the final dyads in this dataset to examine with respect to the potential functional significance of PFC exchanges. To understand how kin might use PFC, we examined adult females as initiators of PFC with their calves, looking at variability by calf age and sex, as well as adult and calf postures and body parts contacted.…”

Pectoral fin contact as a mechanism for social bonding among dolphins

“…Another way to examine social bonds between two specific individuals is by examining the exchange of affiliative behaviors as compared to other pairs within a group; exchanging a large number of affiliative behaviors would constitute a strong social bond (Massen et al, 2010). One well-studied example of affiliative behavior used by dolphins is sharing of pectoral fin contact (e.g., Dudzinski, Gregg, Ribic, & Kuczaj, 2009;Dudzinski, Gregg, Paulos, & Kuczaj, 2010;Dudzinski et al, 2012;Dudzinski, Danaher-Garcia, & Gregg, 2013;Johnson & Moewe, 1999;Mann & Smuts, 1998;Paulos, Dudzinski, & Kuczaj, 2007;Sakai, Takeda, & Kohshima, 2006a, b).…”

Body Contacts and Social Interactions in Captive Odontocetes Are Influenced by the Context: An Implication for Welfare Assessment

“…Because pectoral contacts have been suggested to reflect social bonds [ 21 , 22 ] and to be negatively correlated with the occurrence of aggressive behaviors [ 23 ], they should be investigated as a potential measure of positive welfare. Body contacts, such as pectoral contacts between individuals, have been frequently studied and described as affiliative behaviors, which can be used to assess welfare [ 24 , 25 , 26 , 27 ]. Body contacts previously described in odontocetes include simple contact (contact with no movement), rubbing (contact with movement) and petting (pectoral fin contact with movement, [ 28 ]).…”