英文關鍵字
swan
chick
close
concept
urbanization
its
effects
birds
young
walks
along
lake
against
background
adult
swans
wild
ducks
cloudy
weather
city
park
duck
bird
urban
waterfowl
cygnet
walk
excursion
weekend
trip
wildlife
mute
serene
calm
effect
help
survival
migration
population
climate
town
journey
reserve
nature
natural
environment
outdoor
watching
beak
wings
family
water
behavior
ecology
conservation
habitat
landscape
peaceful