Keepers at an Essex zoo are preparing for the thunder of tiny feet.

Colchester Zoo has confirmed that two more baby elephants are on the way.

It follows the arrival of Kito to mother Tanya last month - the first elephant calf to be born at the zoo through artificial insemination.

Unlike the zoo's recent high-profile baby, the latest expectant elephant has become pregnant naturally.

Breeding programme

Rosa was mated successfully with Colchester's bull Tembo and the new arrival is due sometime around Easter 2004.

The latest conception is another triumph for the zoo's breeding programme.

Tanya's sister Zola's calf is due in December.

The zoo's baby boom is down to better ways of measuring hormone levels in elephants.

Regular monitoring has enabled keepers to know exactly when it's a good time to mix the females with Tembo.