英文關鍵字
wildlife
fly
flight
day
nature
outdoor
freedom
background
swallow
birds
sky
twilight
light
migration
swarming
herd
pattern
population
wings
ornithology
panning
forage
weather
air
behavior
bevy
birdwatched
change
chaos
climate
blue
ecology
morning
animal
tranquility
aerial
becloud
cloud
season
slow
motion
flying
black
flock
overcloud
swallows
abstract
cross
environment