Who is stronger? A lonely leopard or cackling hyenas? And which one is best at dealing with people?
Researchers from the University of Copenhagen studied this closely in a large East African nature reserve surrounded by rural settlements. The research shows that the presence of people has a direct impact on the competitive relationship between the two major predator species: leopards (Panthera pardus) — the iconic spotted cat and the spotted hyena (Crocuscrocus) – a kleptoparasite and pack hunter known for his comical appearance and characteristic ‘laugh’.
“We humans continue to push our way into what little wilderness remains in the world. While we do that, we influence nature. This study shows that human disturbance upsets the balance between competing species and that this benefits hyenas,” said Rasmus W. Havmøller, the first author of the study and a postdoc at the Natural History Museum of Denmark at the University of Copenhagen.
Havmøller has been using camera traps for months to observe the dynamics between hyenas and leopards living in Tanzania’s Udzungwa Mountains – a national park of about 2,000 km2 that is completely surrounded by agricultural and populated areas. The study is the first to combine camera observations of large predators, both in time and space, into a single analysis.
Although the hyena appears to be increasing in numbers as a species, the leopard population has been declining significantly for decades, both in Africa and globally. Since hyenas are the leopards’ only competitor in this particular nature reserve, the ability of the two species to coexist is important for their survival. And here the local population is an important factor:
“Because the local population certainly does not like leopards, the leopards withdraw as far from humans as possible. Hyenas, on the other hand, benefit from the fact that people do not feel threatened by them and do not chase them. live close to human populations and can even exploit humans as a shield against the leopards,” says Havmøller.
“But the areas closest to humans are also the areas with the most prey. And as hyenas claim dominance over these areas, this increases their ability to outcompete leopards and potentially threaten the leopard’s ability to adapt,” adds Havmøller.
Size matters
The researchers’ observations confirm that size matters. While male leopards, which are larger, maintain their dominance over hyenas, the situation is different for female leopards, which are smaller.
“Even though it is the male leopards who are in charge, the hyenas are not particularly deterred by it. They just hang out in the background – probably to follow the leopards and steal their prey. But the physical inferiority of the hyenas appears to be compensated in the areas closest to humans, as male leopards withdraw,” says Rasmus W. Havmøller, who continues:
“Female leopards, on the other hand, completely change their behavior when there are hyenas in the area. They become diurnal, while hyenas are mainly nocturnal. This is probably because female leopards are smaller than hyenas, and they are likely to lose in any fight. above prey.”
Overall, the research shows that the hyenas benefit from living near humans.
“This suggests that the hyena’s ability to adapt to areas of human activity may strengthen their overall success as a species and their competitive advantage over other large predators, as we humans increasingly disrupt nature,” says Havmøller.
When leopards are put under pressure, cascading effects can occur
According to the researcher, the shift in hunting patterns of female leopards could have negative consequences:
“If you open up to more tourism and build more roads in the national park, the female leopards will immediately come under pressure. They cannot distinguish between safari tourists – who are most active during the day – and poachers. Over time, they will probably learn that safari guests are not dangerous. But if there is a large and rapid influx to the area, you will likely see a decline in their population,” says Rasmus W. Havmøller.
If leopards are seriously pushed out of the food chain, one can expect the emergence of so-called cascade effects in the ecosystem:
“Plucking a large predator like leopards out of the food chain, which could be the ultimate consequence of human disturbance, could have very violent consequences. Populations of other species, such as certain monkeys, whose populations are kept in check by leopards, will suddenly grow too large and change the balance of the entire ecosystem,” says the researcher.
As such, Havmøller hopes the research will serve to encourage restraint when it comes to managing nature reserves.
“Our results clearly indicate that human disturbances can change the competitive balance between key predators, so I hope that considerations will be made when expanding activities in wilderness areas, to roll them out slowly and allow animals to adapt .” it would be good if the consequences of human disturbances were monitored in more places using camera traps,” concludes Rasmus W. Havmøller.
HYENAS VS. LEOPARDS
- Leopards are not popular among locals in many places because they prey on livestock and attack people. Hyenas, on the other hand, “clean up” by eating sick or dead livestock and pose no problem to humans.
- Female leopards (approx. 20-43 kg) are about half the size of male leopards (approx. 51-72 kg). Hyenas are in the middle range in terms of weight (approx. 48-56 kg).
- Leopards are solitary hunters, while hyenas hunt in large clumps (clans), which can be an advantage for hyenas in confrontations with leopards.
- Hyenas are kleptoparasites that regularly steal the prey of other carnivores, including leopards.
- Leopards, on the other hand, are master tree climbers, which allows them to protect their prey from hyenas.
