First account of apparent alloparental care of a long-finned pilot whale calf (Globicephala melas) by a female killer whale (Orcinus orca)

Abstract

Interactions between killer whales ( Orcinus orca (Linnaeus, 1758)) and long-finned pilot whales ( Globicephala melas (Traill, 1809)) have been documented on numerous occasions, usually involving predation events and pursuits. Here, the first documented account of a long-finned pilot whale calf seen in echelon position with one killer whale in a group of three killer whales is described, along with one further interaction of the same killer whale group with other long-finned pilot whales. Behavioral, locational, and photographic data were recorded and analyzed for killer whales between 2011 and 2022 and for long-finned pilot whales between 2019 and 2022 off West Iceland. The data were used to obtain background information on the killer whale group involved in the apparent alloparental behavior. The described event also presents the first documented account of epimeletic behavior of a killer whale toward a non-conspecific. The movements of the same killer whale group in conjunction with other killer whales during a subsequent interaction with a group of long-finned pilot whales do not fit any previously observed behavioral patterns described for interactions between these species and may represent an active effort to obtain another long-finned pilot whale calf. Long-finned pilot whale and killer whale interactions might be more complex than previously thought and influenced by multiple drivers.

Agonistic interactions initiated by adult bottlenose dolphins on Antillean manatee calves in the Caribbean Sea

“…For Case 1, these behaviors could be interpreted as dolphins engaged in affiliative behavior, and possibly, some degree of alloparental care. Alloparental care, defined as caring for the young of nonrelated conspecific young [49], has been recorded in hundreds of vertebrate species [50,51], including cetaceans such as sperm whales (Physeter macrocephalus) and several delphinid species [52][53][54]. In contrast, the separation of the calf from its mother in Case 4 did not resemble to alloparental care and suggest that the dolphins may have been trying to separate the calf from the mother.…”

Harassment and killing of porpoises (“phocoenacide”) by fish‐eating Southern Resident killer whales (Orcinus orca)

“…Epimeletic behavior occurs when an individual shows seemingly altruistic actions towards another that is ill, dying, or dead; in cetaceans, epimeletism is often characterized by one or more adults keeping a conspecific afloat or attempting to “resuscitate” it (Bearzi et al, 2018). Recently, a killer whale off West Iceland was seen with a long‐finned pilot whale ( Globicephala melas ) calf swimming in echelon position (Mrusczok et al, 2023), leading to further discussion of possible epimeletic behavior across cetacean species. Epimeletic behavior has been observed in adult females of all three SRKW pods, and that which has received the most attention was J35, when in 2018, she carried her dead neonate for 17 days and 1,600 km (Shedd et al, 2020).…”