African black-footed penguins (Spheniscus demersus) replaced Humboldt penguins (S.humboldti) as the outdoor penguin species at Zoo Antwerpen after the 2013-2014 restauration of the Rotunda Building. The Humboldt penguins lived in an old and rather outdated enclosure that has now been demolished for several years, and was located where now the big restaurant's terrace can be found. They were moved to Planckendael in late 2013 or early 2014 to help establish the breeding group in Planckendael's large penguin and flamingo aviary.
The current penguin enclosure is not very big (and appears perhaps a bit smaller in this picture than it truly is) but it is adequate for the number of animals kept I think.
The wires you can see are made of material such as fishing line or harp/piano wire and are probably meant to keep wild herring gulls and grey herons from getting into the enclosure and eating the penguins' fish or injuring them.
Also note that the original old blue hardstone and chocolate brick foundations of the former aviaries were conserved and now support the new fences and pools.
