What do you do when the animal you’re studying always hears you coming long before you have any clue they’re even around? That’s been the question at the core of pygmy hippo research for decades now. The pygmy hippo is uniquely difficult to research, owing to its nocturnal activity patterns and amphibious lifestyle within the marshy and thorny rainforests of West Africa. In 2023 IBREAM booked a major breakthrough in this project by adding a non-human scientist to the equation, as cute as he was clever: a dedicated pygmy hippo detection dog! In 2025 we hope to upscale that short pilot study and harness their special skills in a field study.
New faces at IBREAM
Heya! My name is Jop Kempkes, I’m a master’s student of biology at Leiden University and currently part of the IBREAM team to perform my research thesis. The pygmy hippo is an animal that has had my adoration since before I could read or write – there’s a big pile of plushies at my mother’s home that can attest to that. Reading about Mark van Heukelum’s study of the pygmy hippo under the IBREAM banner is what inspired me to go into conservation ecology. It is extremely exciting and a great honor to now be part of this group of wildlife biologists. Let me introduce you to the rest of the team!
The star of our crew is Bentley, a three-year-old Malinois. He is blessed with both an amazing nose and an insatiable love for his toy ball, making him a great pygmy hippo detective. We are currently working hard to refine his skills using pygmy hippo feces collected by IBREAM in Taï National Park in 2022. The hard-working trainer making all of this possible is Rene Eijkelenburg of Stichting Wildlife Solutions.
Even more precise
We are innovating on the training methods used in 2023 in two ways. Firstly, to fine-tune Bentley to the olfactory profile of the pygmy hippo, we are already introducing him to the ‘distracting’ scents of other West African mammals during the training phase. It turns out that that is a very valuable step, as Bentley initially also responded to chimpanzee scat! Luckily, he quickly learned to ignore chimps and he seems to have no trouble with the other feces we collected from Safaripark Beekse Bergen.
Secondly, we are also testing how the ‘age’ of pygmy hippo feces influences their detectability to Bentley. The Hortus botanicus Leiden has allowed us to use their greenhouse to simulate the tropical conditions needed for this experiment, and ZooParc Overloon has supplied us with the necessary pygmy hippo dung!
To make sure the delicate scent of the feces decaying in the Hortus doesn’t get contaminated, they are placed inside a finely grated crate. Safe from disturbance, but still in touch with the tropical climate!
Bentley will be our ‘pygmy hippo detector’ in the rainforest. The samples we find will later be passed on to Hummel, a female field trial labrador. Mariska Snelleman, head of the conservation detection dog program at IBREAM and CEO of Conservation Dog Services, is training Hummel to not just recognise pygmy hippos, but actually tell the difference between the poo of males and females. Why are we interested in that? Well, in zoos more females than males are born for unknown reasons. In addition, we also have reason to believe females occupy smaller territories than males. All of this definitely warrants further investigation!
Because we won’t have access to a freezer for our samples in the rainforest, we will soon be beginning a study into alternative preservation techniques for fecal scent at ambient conditions using samples donated to IBREAM by ZooParc Overloon and Zoo Duisburg.
Could it be the plants?
Did you know pygmy hippos don’t “simply” need a beautiful rainforest in order to feel at home? Some parts of the forest are relatively dense in pygmy hippos, in other areas the chances of finding one are very low. Currently we don’t really understand this pattern. Previous projects have looked at poaching and the proximity to rivers as possible culprits, but those don’t seem to fully explain the pattern. That has led to a simple question that we hope to answer during IBREAM’s fieldwork in 2025: could it be the plants?
There are at least 1400 species of plant in Taï NP alone. Those don’t occur randomly, but are part of distinct patches of forest that all have unique properties. Factors that the pygmy hippo probably cares about quite a lot – visibility, humidity, light penetration – all depend on the vegetation. And of course, pygmy hippos also eat plants! From what we know from studies like those of IBREAM’s very own Alba Hendier, the pygmy hippo has a unique diet. It’s broad, but they show preferences for some specific plants that other animals couldn’t care less about.
We are very eager to start unravelling the ways in which the pygmy hippo interacts with its environment, in doing so gaining knowledge relevant to both conservation planning and future research. The IBREAM team will be in Taï NP to collect data for this project in early 2025. Many more bold plans are currently in the making at IBREAM for the months and years after that, so stay tuned as we will soon be in touch to tell you more!
Schooling a dog to recognize poop takes buckets full of ‘homework