Bachelor groups of ring-tailed lemurs are common in zoos, but not in the wild. That is why we have closely observed our ring-tailed lemurs for months. Result: They have their social preferences and form real bonds with their best buddy´s!
Male fiddler crabs can only eat with their little claw. They don't compensate for this by eating longer, and they just eat a little faster with their one claw. But they are more selective when it comes to feeding places!
Few animal species recognize themselves in a mirror. Some great apes succeed in this, as decades old experiments show. But because these experiments were carried out in a way that no longer corresponds to today's scientific criteria, they were repeated. Only our chimpanzees, but not the gorillas, showed signs that they recognize themselves.
71 eagle rays have been born in Burgers' Ocean by now. We have developed a method to conduct paternity tests from the genetic material in their venomous sting. Knowing the parentage is important for the studbook of this endangered species.
All kinds of micro-organisms live in the coral basin of the Burgers' Ocean. Water samples were examined by specialized scientists. They found 55 species of the unicellular, shell-bearing foraminifera. Their skeleton can be used to study climate change, which is why many scientific institutes now want our water samples!
In order to keep our sharks and rays healthy, records are kept of who eats how much. A great deal of knowledge has been assembled over time about the best diet for sharks and rays. The eagle rays now get food 12 times a week, the black-tipped reef sharks only 3 times.
A couple of aquariums and museums around the world are currently working together on compiling a large database of stony corals. Species determination in this group is rather difficult. So we collect DNA material and take macro photos of the living corals and their skeletons. We will soon know more about the species in our aquarium. The database will also be useful for protecting endangered corals in the wild.
Aardvarks are nocturnal in the wild. So we wanted to know what our aardvarks are up to at night. Infrared cameras give a good picture of their circadian rhythm (the 24 hour rhythm). There are significant individual differences, but our aardvarks seem to be most active between 4 and 9 in the morning.
Tiny numbers were glued onto the wings of the blue morpho butterflies and a blob of nail polish was painted on as well. This enabled students to follow them through our Mangrove. We now know that the males fly around a lot more than the females. The blue morpho butterflies prefer some places in the Mangrove and avoid others.
Do young sun bears know a transition point in their development at which they become suspicious of new stimuli? We received this research question from rehabilitation centres for these bears. We tested it by presenting tour bear cubs with a new smell, sound, or object three times a week. Result: they always remained open and curious!
There are more animals, mushrooms and plants in our ecodisplays than we ever put into it! Our mini rainforest, for example, is a scientific paradise for experts in the field of for example woodlice, flatworms, freshwater snails and ants. Every year a couple research groups come to study the biodiversity in our Bush.
The members of the Dutch zoo association NVD work together on a solid, scientifically correct and practical method to measure the welfare of zoo animals. This makes the data more valuable and usable. More than 80 questions about behavior, enclosures, food and health are asked for each individual. This year it's the turn of the big cats!
Researchers noticed that some of our female chimpanzees have developed their own tradition: they walk with their arm crossed in front of their chest. After two new females arrived, one of the two took over this quirk within a short time. This female integrated faster and developed more friendships. Coincidence?