Hundreds of birds which were found dead on a road died due to trauma from impact with the ground, preliminary findings have indicated.
About 225 starlings were found dead on a lane on Anglesey on 11 December.
The Department for the Environment, Food and Rural Affairs is continuing its investigation, but it is unclear why the birds plunged to the ground.
Dafydd Edwards, whose partner found the birds, said it was as if “they had dropped down dead from the sky”.
Defra added it had investigated several incidents of mass mortality in groups of starlings previously. It said testing for bird flu was negative.
North Wales Police said it believed it had an explanation into the deaths on Wednesday.
What are starlings?
- Smaller than blackbirds, with a short tail, pointed head, triangular wings, starlings look black at a distance but when seen closer they are very glossy with a sheen of purples and greens
- Noisy birds, starlings spend a lot of the year in flocks
- They usually lay 4-6 eggs in mid-April
- Starlings are very tenacious and adaptable birds
- Over the centuries they have expanded their numbers and range in the wake of farmers, wherever suitable conditions became available. They used to be uncommon birds in the UK
- Starling numbers have declined markedly across much of northern Europe and the UK. The decline in the UK started during the early 1980s and has continued ever since
- Long-term monitoring shows starling numbers have fallen by 66% in Britain since the mid-1970s