Elephants have a hard time getting privacy after mating. The events following mating are anything but silent and instead are referred to as “mating pandemonium”¹. After an elephant couple has mated, nearby elephants become curious. They surround the mating site and emit bursts of vocalizations². Large-frequency roars, rumbles, and trumpets decorate the air and invite other elephants to join in. These loud and contagious vocalizations are followed by olfactory searching as nearby elephants sniff the mating site with their trunks. On a podcast about mating pandemonium for PRI, the event was described by the director of ELP, researcher Peter Wrege as an “elephant party”². In a typical “mating pandemonium event”, elephants — young and old, familial or unrelated, male or female — all crowd together, ears flapping and heads raising. While similar behavior of post-copulatory vocalizations has been observed in some primates and bats³, “mating pandemonium” is singular to elephants.
After an elephant mating, there is increased olfactory and auditory behavior for several minutes in the mated couple and nearby elephants³. Elephants emit chemical signals when they are ready to mate, and these chemicals called pheromones are deposited in fluids at the mating site. Chemical signals can be picked up by nearby elephants who peruse the site with their trunks, thus explaining the increased olfactory behavior. Information received from dropped fluids can be used to deduce male motivation to mate or whether the female has increased fertility.In general theory, males want to mate with as many females as possible. However, females are very interested in fluids at the mating site. They will scavenge the site for pheromones or substances in semen in order to deduce the male’s status before mating(as the likelihood of meeting males regularly from other forest groups is rare and so an informed decision can be beneficial).
Much of the explanations for mating pandemonium are proposals; the truth is that mating pandemonium behavior is a bit of a mystery and it is up to researchers to provide possible explanations. Majority of ELP’s recordings are at night, such as the thermal imaging video included above. Elephants typically enter forest clearings at nighttime and this allows researchers to visually observe their behavior. ELP researchers already heard increased vocalizations from auditory units, but this trumpeting and roaring was further paired with night footage. An entire group of elephants can be seen roaring and rumbling after a mating event. Researcher Mya Thompson from ELP wanted to make sense of this particularly noisy disorder. What is the purpose of increased auditory behavior that is so characteristic of mating pandemonium?
Thompson observed 16 mating events in African forest elephants and analyzed auditory recordings as well as night film footage³. It was difficult to pinpoint who started the rumbling, but it was clear that a majority of the group was involved. This behavior had to serve some benefit, so Thompson looked at possible advantages for individual group members. In the 16 events observed, the mated female often emitted post-copulatory vocalizations that Thompson hypothesized either attracted other mates or (if she liked her mate) enhanced mate-guarding. Likewise, mated males also made post-copulatory vocalizations in much the same regard. These post-copulatory vocalizations are included in the mating pandemonium choir, but this phenomenon consists of much more than a duet.
Not only does the mated couple create post-copulatory vocalizations, but family members will join the cause as well to possibly attract more mates for their sexually-active relative³. There is an indirect fitness value for family members, where continuing one’s lineage is a motivating factor. Perhaps more interesting is the value for non-related elephants who join the chorus (where no obvious fitness benefit is gained). Elephants are the only species where non-members have been observed in this post-copulatory group behavior, and yet it was often non-familial members who made up the majority of elephants investigating the mating site. Due to elephants’ long life spans and memory, this behavior may follow the idea of reciprocal altruism: that an elephant will call and help attract mates for a sexually receptive non-relative given that the behavior is reciprocated at a later time. Though a compassionate sentiment, Mya Thompson explains that this hypothesis is not very likely; forest elephants travel in groups scavenging for food and it is rare to regularly meet individuals from other groups. Another justification Thompson offers is a form of ‘social eavesdropping’ where non-relatives may alert their sexually receptive family members that a sexually active elephant is close-by or to assess the status of the mated couple(either to determine if a valuable mate or a form of gossiping).
Though there are many questions left unanswered, “mating pandemonium” is a striking and unforgettable event. It is impossible to ignore by both elephants and researchers who have observed this phenomenon in the wild. While the event appears as a kind of elephant party or celebration, there may be more underlying motives as to why these behaviors exist. Exciting and novel (only observed in forest and savanna elephants, and recently discovered with night vision cameras to mainly occur at night²), “mating pandemonium” is still a mystery with our top-notch detectives at ELP working on the case.
¹Poole, J H; Payne, K; Langbauer Jr., W R; and Moss, C J 1988. The social contexts of some
very low frequency calls of African elephants. Behavioral Ecology and Sociobiology 22:385–392.
²Peter Wrege, Interview on Science Friday, National Public Radio
Lim, A. (Producer). (2014, August 14). Researchers are unlocking ‘mating pandemonium’ and other secrets of forest elephants [audio podcast]. Retrieved from https://www.pri.org/stories/2014-08-14/researchers-are-unlocking-mating-pandemonium-and-other-secrets-forest-elephants
³Thompson, M.E. et. al. (December 15, 2014). African forest elephant (loxodonta Africana cyclotis) vocal behavior and its use in conservation (Master’s thesis).