Mandatory Credit: Photo by Dave Stevenson/REX Shutterstock (5279967b) Ring-tailed lemur (Lemur catta) with a green Frankenstein s Monster mask Lemurs try on Halloween masks at Whipsnade Zoo Bedfordshire Britain - 20 Oct 2015*Full story: http://www.rexfeatures.com/nanolink/rbr3 A group of playful ring-tailed lemurs are getting in the Halloween spirit early this year ahead of ZSL Whipsnade Zoo?s half-term activity week Boo at the Zoo. The lemurs so named after the ghosts of Roman mythology (Lemures) are leaping at the chance to mess around with the spooky masks that Zookeepers have been collecting for the event. Team Leader Mark Holden said: ?Our inquisitive and playful group of ring-tailed lemurs will no doubt be very curious to investigate the colourful Halloween masks so it will be a great enrichment activity for them. We will also hide some tasty treats like raisins in the masks to make it extra fun. Ring-tailed lemurs are classified as Endangered by the IUCN Red List of Endangered Species due to habitat destruction hunting for bush meat and the exotic pet trade. Ten baby ring-tailed lemurs have been born at ZSL Whipsnade Zoo within the last two years as part of the European Endangered Species Programme.