The familiar sound of the Kittiwakes is less evident now that it was when we first visited the seabird colonies at Hermaness, Noss and Sumburgh back in 1987.
Kittiwakes have been studied for some while in Shetland and it has been found that 58 colonies exist. Back in 1969-70 Operation Seafarer Census discovered over 47,000 nests and in the early 1980's numbers increased to over 54,500 (1981). Since then numbers have been dramatically reduced due to food shortages, especially Sandeels which then normally collect near the surface of the sea. In the 1992-02 survey numbers dropped to 25,800.
It is thought some Kittiwakes abandon the colonies in Shetland and moved south to Orkney where numbers increased in the late 1980's. Laying is often delayed to coincide with food availability but even in good years eggs are taken by Ravens and Hoodie crows, with the young taken by Gt Skua and Gt BB Gulls, keeping numbers low.
At Sumburgh a well studied area, during 2001-2003 productivity was nil, with only a slight improvement the following year.This colony has remained stable since 2005 with around 355 nests, this being mainly due to the adults being long lived.
Kittiwakes have moved to another food source with the preferred food, Sandeels getting harder to come by. These are pipe-fish which seem to be more abundant. But having watched an adult bird taking around 10 mins to swallow one, you can see why so many young birds choke to death.
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