He may be one of Ireland's most famous residents, and he might be about to celebrate his first birthday - but that doesn't mean Kituba the baby gorilla always gets his way. As these pictures from Dublin Zoo show, the infant was left frustrated after he tried to grab a banana from his mother Lena - who made sure she got to enjoy the snack herself. The stern mother was obviously in no mood for any monkey business and even struck a threatening pose for the cameras after devouring the treat. Out of reach: Kituba tries to get his hands on the banana, but mum Lena shows him who's boss The pair are residents of Dublin Zoo's Gorilla Rainforest, a £2.5million development consisting of 12,000 square meters of undulating forest that is the perfect habitat for the zoo's breeding troop of western lowland gorillas. Tomorrow the zoo will kick off a weekend of celebrations to mark Kituba's first birthday, when the rainforest will be transformed into a funfair filled with family activities. Kituba was born on March 30 last year weighing just 1.81kg. Keepers were initially unable to tell whether he was male or female because Lena was so protective of the infant. The birth was heralded as 'a great success for the European breeding programme for these critically endangered primates'. Mother knows best: Gorillas are known to be protective of their young - and clearly Lena is no exception Birthday boy is taken for a ride: Kituba gets a lift from his mother source:dailymail