A team of researchers has unraveled the complex relationship that exists between both animal species around carrion.

A hyena devouring another species.

The lions (Panthera leo) and the spotted hyenas (Crocuta crocuta) compete for the same fangs, mainly ungulate mammals of medium to large size. The one can snatch the prey hunted by the other, and vice versa, in an interaction called kleptoparasitism.

However, the scavenging habits of these two species go much further, so that both carnivores take advantage of practically any corpse that they find in their surveys of the territory. In fact, they sometimes consume more carrion than live prey. But how do lions and hyenas interact with carrion?

A team of researchers, led by the University of Granada (UGR), has just published a study in the journal Oikos which tries to answer this question. The field work was carried out in two natural reserves of South Africa, one with lions and hyenas (Hluhluwe-Imfolozi Park) and another with hyenas, but no lions (Mkhuze Game Reserve), both in the Zululand region.

The fight between corpses

“The pattern of carrion consumption was similar between both species, although we found important differences”, he explains. Marcos Moleón Paiz, a researcher at the Department of Zoology at the UGR and one of the authors of this work. “For example, lions showed a higher preference by carcasses of large animals, while the hyenas also took advantage of the smaller corpses, which were practically ignored by the lions ”, he continues.

The data indicate that, when both species are present in the same carrion, the lion is the dominant species, especially when an adult male appears, taking into account that the probability of encountering the same carrion is greater as the size of the carcass increases.

“The hyenas modify their behavior in the presence of their competitor“Moleón continues. “On the one hand, they have to give part of the food to the lions. On the other hand, they become more diurnal than in the area where there are no lions, where they are genuinely nocturnal and twilight ”.

Interestingly, the relationship between lions and hyenas also includes positive interactions. For example, “hyenas find carrion faster if lions are already present, probably because the former listen, smell or even actively follow the latter,” says the researcher.

This work reveals that, in order to guarantee the long-term coexistence of lion and hyena populations in the same area, particularly in the case of small nature reserves, it is important procure a varied supply of prey, which includes megaherbivores like elephants and rhinos.

“Unfortunately, the populations of these megaherbivores are being dramatically reduced due to the trafficking of elephant ivory and rhinoceros horns, which is increasing in these times of little environmental surveillance due to the Covid-19 epidemic”, laments the researcher of the UGR.

A long experiment

The development of this work has required years of intensive field work. The samplings consisted of place dead animals of different sizesFrom chickens sourced from a local farm to wild animals such as impalas, nyalas, wildebeest, buffalo, rhinos (black and white) and elephants.

In front of these corpses, one or two camera traps were placed that caught all the scavengers that were approaching. Once the carrion was consumed, the cameras were removed and the photographs analyzed. In total, 6,927 photos of scavengers were obtained, including 789 of lions and 2,133 of hyenas.

“In the case of some buffaloes, rhinos and elephants, when we got to the corpse we found that the lions had been ahead of us or hyenas. So we had to scare them a few meters for the minutes we needed to be able to position the camera. In these situations, for safety reasons, we were always accompanied by a ranger armed with a rifle, although it was never necessary to shoot, not even in the air ”, says the scientist.

To do this, Moleón lived in one of the reserves (Hluhluwe-Imfolozi) for two years, in a small camp surrounded by an electrified fence. “Having the opportunity to experience Africa from within is an absolutely magical and unforgettable experience, both personally and professionally. Since I first arrived in Zululand in 2010, a good part of my research career revolves around the megafauna of the African continent ”, comments the UGR researcher.

“Future projects in this continent go through studying how the presence of these large carnivores influences the ‘landscape of fear ‘ of the rest of the animals of the savannah, and how the African megafauna in general can be an economic engine for African society ”, he concludes.