Let's Talk Primates: An unusual type of pest

Berenty is overflowing with lemurs. They’re everywhere. They’re completely habituated (used to humans). I can hear the ring-tailed lemurs and the brown lemurs on my roof, foraging on the tree above. I see brown lemurs multiple times a day drinking water from our well or from large puddles. I’ve only seen a sifaka drinking from the well once so far. The ring-tailed lemurs are very daring: they are in the kitchen, running around outside our houses, even in the dining room on the table. They’ll steal whatever food is left out and they’ve been known to sneak off with whole loaves of bread. They raid our garbage as well and anything that’s left behind in the kitchen. They sit on top of the roof. They sit on the side of the houses. They feast on the cactus that grows near us. They steal the cat’s food. Ring-tailed lemurs are basically like rats here. Being everywhere, they of course poo everywhere, which is not so cute.

Brown lemurs drinking our water

Ring-tailed lemurs are also up in the tourist section of Berenty. In this part of the reserve, they enjoy stealing leftovers from the tourists’ meals and occasionally being fed by employees, even though this is forbidden. It sounds cute and the tourists happily snap humorous photos of lemurs eating banana peels or jumping on tables, but the reality is different. Feeding or provisioning animals leads to multiple problems. For starters, aggression within the troop will increase, causing physical confrontations and injuries and potentially increased infant mortality. The increase in aggression causes an increase in stress, making animals more vulnerable to disease. Animals become dependent on this outside source of food, causing a serious problem if at any point humans decide to stop provisioning the animals. Once used to a steady source of food, the troops may no longer have a large home range and the ability to expand and search for alternative food sources without entering into another troop’s territory, again leading to increased physical confrontations.

Ring-tailed lemur sauntering into our kitchen

Provisioning cute, little lemurs seems like a good idea at a first glance, but there are drawbacks that should be considered. Provisioning a group of primates is not a decision that should be entered into lightly. Yet there are troops of primates around the world where provisioning takes place and has so for years. These unique, experimental environments allow researchers to ask novel questions that wouldn’t be possible otherwise. For example, we know that provisioned populations generally have higher birthrates.

Critical thinking: What other questions might be asked if studying a provisioned population of primates or other animals?