Two male ducks are driving park keepers and their female counterparts quackers by refusing the advances of the opposite sex for each other.

The Swedish shelducks have ignored calls from female ducks over the last three years and appear to deliberately stick together.

Lennarth Blomquist, bird manager at the park, told the TT news agency, “We can state that they act exactly like a couple (composed) of a man and woman, the bigger one always defending the smaller duck.

“Shelducks mate for life.”