An unusual case of care‐giving behavior in wild long‐beaked common dolphins (Delphinus capensis) in the East Sea

Underwater observations of dolphin reactions to a distressed conspecific

“…Consequently, we elected to focus on the presence or absence of the BDD^whistle contour. Caldwell and Caldwell (1966), Dudzinski (1996), Pilleri (1984), and Park et al (2012) BOther whistle contours^were defined as any other narrowband, frequency modulated vocalization not categorized as a BDD whistle contour.^All Bother whistle contours^were grouped into one category, as the whistler's identity in these cases could not be reliably determined.…”

“…For example, healthy dolphins may attempt to assist and perhaps stimulate a distressed conspecific through various pushing and lifting behaviors that support the animal at the surface (de Moura, da Silva Rodrigues, & Siciliano, 2009). Such epimeletic behaviors have been observed in both captive and wild populations in a variety of cetacean species, including rough-toothed dolphins, Steno bredanensis (de Moura et al, 2009); long-beaked common dolphins, Delphinus capensis (Park et al, 2012); La Plata dolphins, Pontoporia blainvillei (Cremer, Sliva Hardt, & Tonello, 2006); and Atlantic bottlenose dolphins, Tursiops truncatus (Caldwell & Caldwell, 1966;Fertl & Schiro, 1994). Caldwell and Caldwell (1966) discussed three different categories of behaviors exhibited by nondistressed individuals during periods of epimeletic behavior: Bstanding by,^Bexcitement,^and Bsupporting.^BStanding by^occurs when animals maintain close proximity to the injured/distressed individual but provide no aid (Caldwell & Caldwell, 1966).…”

“…Park et al (2012) observed several wild long-beaked common dolphins, Delphinus capensis, in the East Sea, engaging in caregiving supportive behaviors directed toward a dying conspecific at the surface. These behaviors included pushes toward the surface, pushes to the head and upper body of the dying animal, and Braft^formations (i.e., several animals using their body to lift the upper and lower body of the distressed individual simultaneously) in order to keep the dying individual at the surface.…”

“…Both nurturant and succorant epimeletic events typically involve only one or two adult dolphin(s) providing support to one other individual, but sometimes appear to involve multiple helping animals (Cockcroft & Sauer, 1990;de Moura et al, 2009;Park et al, 2012;Ritter, 2007;Siebenaler & Caldwell, 1956;Warren-Smith & Dunn, 2006). Park et al (2012) observed several wild long-beaked common dolphins, Delphinus capensis, in the East Sea, engaging in caregiving supportive behaviors directed toward a dying conspecific at the surface.…”

“…Their observations were the first documented account of multiple adult animals simultaneously providing succorant epimeletic support toward the same individual. However, the account by Park et al (2012) did not include an examination of the acoustic signals being emitted by any of the animals during the encounter.…”