Lucky citizens of Portugal's capital, Lisbon have been fortunate enough to catch a rare sighting of dolphins off its shores as they came out of COVID-19 lockdown.

Although dolphins have been previously seen in Lisbon's Tagus river, they are no longer seen very often, according to a report by the Sea School and the Marine Science Association in Lisbon.

The dolphins have been seen in groups or 'pods' leaping out of the water, looking like they were thoroughly enjoying themselves. 

It is not known why dolphins have returned to the Tagus, but Lisbon's mayor's office believes it is to do with the drop in water pollution in recent months. 

"With the improvement in water quality, the river has been gaining new life and a friendly family of dolphins has been seen several times during the last month," the mayor's office wrote on Facebook.

Water pollution has dropped across Europe since the lockdown began, with many areas reporting an increase in wildlife. 

Marine biologist, Francisco Martinho, who specialises in dolphins, believes the increase in fish in the area to eat is the reason dolphins have returned. 

Video editing: Pedro Duarte