They used to rank alongside a slice of cake in a party bag and pass the parcel as mainstays of a children’s birthday party. But clowns are increasingly being frozen out of the celebrations as children are more interested in seeing performing Disney characters and pirates than juggling and animals balloons.In the face of stiff competition from characters in films such as Frozen and Beauty and the Beast, the clown is struggling more than ever for bookings and the oldest organisation to support the act of clowning has warned that clowns are in danger of dying out.Clowns International, set up in 1946, says that there are now only about 100 registered clowns in the country, and that the situation is getting worse.Mattie Faint, from the body, said: “There aren’t so many clowns around these days. I think most clowns are children’s party clowns, rather than, say, being part of a circus, but now children want Disney characters or pirates so the times have changed. At one point the only person you ever saw at a child’s party was a clown – now it can really be whatever they like.”Now, in an attempt to save their reputation, a new exhibition run by Clowns Gallery Museum in London, which details the history of the clown, will be touring the country to celebrate the 250th anniversary of the circus. The eggs, which are made from clay, make up the Clown Egg Register, which represents an informal copyright to clowns who design an egg based on their facial make-up.In fact, the register proves such interesting viewing it has been captured in a book by Luke Stephenson and Helen Champion.The practice of painting eggs began in the Forties by the late Stan Bult, founder of the International Circus Clowns Club, now Clowns International. As a clown enthusiast, he would capture the appearances of various clowns by painting them on to hollowed-out eggs as a way to copyright their facial features, ensuring that no two clowns looked the same. To prevent the theft of a clown’s face, members of Clowns International must painstakingly paint their clown faces onto eggs Eventually the collection grew into what is now the Clown Egg Register.Mr Stephenson, photographer of the latest edition of The Clown Egg Register book, said: “While I haven’t seen any particular trends in the eggs, the personas of the clowns are certainly captured in the paintings.“They are quite remarkable little things and something quite unusual but interesting to photograph.”Mr Faint added: “We’re now holding a number of events this year and we really hope this will help boost the popularity of clowns. Maybe parents will see the display of eggs and it will make them consider that for their children.” The museum, which is curated by Mr Faint, is planning to put more than 150 clown eggheads on display as part of the tour. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.