Two kestrels in flight, flying large arcs & repeatedly hovering high above tree over the past 3-4 days. This evening one has continued to fly wide arcs and the other has broken off, windhovering then dropping to raid goldfinch nest in garden-bordering hawthorn, in an area rich with small rodents near open field and train tracks. Nest raided 3 times in total within approx 10 minutes - unsure whether by one bird or both. Stockton, 18:50