There are fewer than 900 breeding pairs of avocets in the UK
Staff at a Wearside wildlife reserve are celebrating the arrival of four rare wading birds.
Avocets traditionally nest in southern England, but since 2006 a pair has returned each year and hatched chicks at the Washington Wetland Centre.
The same birds recently arrived and have now been joined by another male and a female.
It is hoped both pairs will nest making the reserve the most northerly breeding colony of avocets in the UK.
The waders have striking black and white plumage and are known for their unique mating rituals in which the male puts one wing around the female and they run forward together with their bills crossed.
Biodiversity warden Giselle Eagle, a warden at the Washington Wildlife Centre, described their arrival as "brilliant news".
She said: "A single avocet male arrived shortly after the existing pair, but was chased off by them.
"He has now returned with a female and they are checking out potential nest sites on the island.
"Providing they have a successful nest, avocets become loyal to the same site for their entire lives, so hopefully this new pair will be returning to Washington for many years to come."