Escort for dead dolphin calf

Escort for dead dolphin calf.

Thomas Troesch reported in Netzeitung 9.10.2001,
that a biologist had observed rough toothed dolphins,
( Steno bredanensis ), carrying and protecting a calf,
for several days, after it had died.

rough toothed dolphin - (Steno bredanensis)

This behaviour has not be documented in such detail before. The biologist Fabian Knight of M.E.E.R. e.V. Observed this rarely documented dolphin behaviour, over a six day period, in the waters around the island of La Gomera, in the Canaries.

A female, in a group of rough toothed dolphins ( Steno bredanensis ), carried her dead newborn calf with her , for several days. She held the calf at the surface, with her lips, melon and teeth, during which time, clear signs of decay could be noticed.

Rarely documented behaviour

The mother was supported in her efforts towards the calf, which had either been still born, or had died shortly after birth, by the rest of the dolphins in the group - such assistance behaviour of whales and dolphins has only been described on rare occasions.

The group of approximately 15 dolphins, to which the female belonged, was seen on six occasions, in five days.

The situation was always the same: The female dolphin constantly remained in the proximity of the newborn calf, and was escorted by two further dolphins.

Different members of the group were seen again and again, in direct proximity to the female.

The whole group swam very slowly during this time, and the group remained in an area of only a few square kilometers.

Support of the group

".. the female received support from the whole group. On the fifth day of our observations, a dolphin from the ' escort ' group, held and even protected the dead young animal, at the surface, from the attacks of sea gulls, interested in the cadaver .", reports the biologist.

Why this behaviour persists for such a long time, is, however, still unclear.
Knight can only speculate here: "the fact the death of a young animal affects the behaviour of a whole dolphin group for days, points to the fact that there are strong social bonds within a group of rough toothed dolphins ….."
Scientists are well aware of this epimeletic behaviour, as it is called, but it has rarely been documented . The reason for it, is not yet clear .
This epilemetic behaviour has also been displayed when dolphins have saved human beings from drowning.

ECBC would like to thank one of our supporters in Germany for sending this article to us.