We had blackbirds nesting in our garden but my wife saw a magpie go into the bush and I think it has destroyed the eggs as I found shells on the ground and the nest is empty.They are now building a nest in the next garden. Should I remove the old nest or will they reuse it next year
Neither. Nests are biodegradable so will disappear in time themselves without need for removal. Blackbirds nest more than once each year, but a failed nest is unlikely to be used again. Nests should never be removed during a breeding season, whatever the species.