St Kilda's kittiwakes in danger say NTS

The number of kittiwake gulls on St Kilda has plummeted to the lowest level ever, with experts fearing that the population is at risk of collapse.

The National Trust for Scotland (NTS), which monitors the archipelago's bird population, has also recorded significant declines in the populations of other seabird species including puffins, fulmars and razorbills.

NTS says a change in the ecosystem has removed a key food source.

Pictures: National Trust for Scotland