Orcas feed on fish, but will also target seals and sea birds, of which there are an abundance around the Farne Islands, off the Northumberland coast.
“The question I’ve been asking myself is not why they’re coming now, but why they weren’t here before,” Kitching said.
There are just two resident orcas in UK waters, two older males named John Coe and Aquarius, who were spotted off the coast of Cornwall on 1 April.
They are the remaining members of the West Coast Community pod of 10 orcas, which was frequently spotted around the UK and Ireland in the 1990s.
Other orcas visit from places such as Iceland, but are more commonly seen in the Shetlands and the west coast of Scotland.