Life through rose-coloured glasses
Antwerp ZOO is continuously innovating to optimise animal welfare. That is why we recently installed special lights for our king penguins. The animals benefit from the broad light spectrum of the LEP (light emitting plasma) lights. The fairly recent light technology includes UV light. Earlier research has shown that purplish or bright pink areas on their beaks become visible in UV light. These beak spots are an indication of the condition of the male or female and could enable the birds to find their ideal mate because the beautifully fluorescent areas only appear once they are sexually mature. The human eye cannot see UV light but penguins, and indeed most species of bird, can. We hope that this effect will enable better matching and thus improve the breeding success of this endangered species. The experiment is unique in Europe.
We seek to house our animals as well as possible and to optimise their welfare, which is why we try to simulate their natural habitat as closely as possible. King penguins are native to subarctic regions, near the Falkland Islands. We therefore choose to simulate the natural light cycle in that region with LEP lights controlled by a special computer system. We simulate the length of the days throughout the year. As the islands are so close to the South Pole, the time between sunrise and sunset varies significantly in the course of the year. Daylight hours are very long there in summer and it barely gets light at all in winter. The enclosure at Antwerp ZOO was renovated in early 2018 and designers sought potential extra lighting innovations. A fairly recent light technique was found in an American zoo.
HOW EXACTLY DOES THE EXPERIMENT WORK?
Based on the American example, LEP lights, or light emitting plasma lights, were installed in the penguin enclosure. This is highly innovative and actually unique in Europe. The lights have a very broad light spectrum and, contrary to ordinary lights, also emit UV light. Earlier research had revealed that penguins have purplish or bright pink areas on their beaks, which become visible in UV light, once the animals reach sexually maturity. These beak spots enable the birds to find their ideal mate.
Earlier research had revealed that penguins have beautifully striped purplish areas on their beaks, which become visible in UV light, once the animals reach sexually maturity.
"If a female, or indeed a male, is in good condition it will have a beautiful fluorescent beak spot. A spot which we cannot see but penguins can thanks to the special lights which emit UV rays", Animal Care Coordinator Jan Dams explains. "Penguins, and by extension most birds, see very differently to people. The human eye cannot perceive UV light. Penguins can and consequently perceive colours differently. Thanks to the UV rays emitted by the new lights the penguins can see the colourful zones that people cannot perceive."
Thanks to the UV rays emitted by the new lights the penguins can see the colourful zones that people cannot perceive.
WHAT IMPACT DOES THE EXPERIMENT HAVE?
Antwerp ZOO hopes that the experiments will improve the penguins’ mate choice. "Penguins look at each other in very different ways”, Dams continues. "Are their feathers glossy? Are their eyes clear? One such aspect is: is UV light reflected on their beak? We now make that possible, thus enabling them to obtain extra information about a potential partner. We hope that this will lead to improved breeding success of this endangered species, which does not reproduce easily." The researchers at Antwerp ZOO will now compare the concrete long-term impact of the lights. Will more eggs be fertilised? Will the penguins pair off more effectively?
We enable them to obtain extra information about a potential partner. We hope that this will lead to more breeding success of this endangered species that does not reproduce easily.