LONDON, Oct. 12 (Xinhua) -- A rare silvery gibbon has born at England's Chester Zoo, which has seen a record baby boom so far this year.

Born to mom Tilu and dad Alven, the highly endangered primate arrived on Wednesday. The tiny pink-faced primate, which is much too small to be sexed, has yet to be given a name.

Zoo officials said the arrival of the endangered primate is the latest in an unprecedented surge of new animal arrivals at the zoo.

Zoo director Mike Jordan said: "This new baby gibbon has arrived hot on the heels of a whole host of other important births."

A total of 733 mammals have been born so far in 2018, far exceeding the previous highest total of 566 in the same time period.

Experts have put the unprecedented period of conservation breeding success down to a range of factors including natural habitats, skilled staff, ever improving levels of care and increasing scientific knowledge of threatened species, said a zoo spokesman.