FEMALE SOLICITATION CALLS – FINDING A MATE
For females of species that are solitary and/or distributed sparsely at low densities finding a mate at the brief period of sexual receptivity (oestrus) offers special difficulties. In this case females need to advertise fertility.
Leopard seals are distributed widely through the Antarctic pack ice. We have shown that females produce specific vocalisations when in oestrus.
Listen here to a females vocalisations.
Picture is of male (left) and female (right) leopard seal calling back and forth to one-another underwater.
We are now looking at the pygmy hippopotamus.
Male hormonal link to calling
In a three-year study of a captive female vocalizing commenced when here measured oestradiol levels were elevated and stopped with the drop in plasma oestradiol. Her behaviour changed and mounting between male and female seals were seen only at this time. This pattern was seen in each of the 3 years.
Vocal signalling may play an important role in advertising oestrus for this solitary seal.