autumn
autumn phenomenon
bevy
bird
bird flocks
bird watching
birding
birds fly
birdwatcher
common scoter
covey
crowd
displaced persons
escape from war
fall
flies winter
flight
flock
group
halfmoon shape
herald autumn
herald winter
herd
high altitude
immigrants
mass
mass displacement
melanitta nigra
migration
migration bureau
migration flow
migration in europe
migration routes
millions of migrants
observation migrations
observers
ornithology
pack
passage
refuge
refugee camps
sadness
school
seasonal migration
signs autumn
swarm
winter
winter harbinger
winterin