Japanese Society for Preservation of Birds
Barometer of a Waterside Environment
Belonging to the same order as plovers and gulls, 28cm in total length,
about the size of a brown-eared bulbul. For most to hear the name “swallow”
or “sparrow” a clear image of the bird should rise. Most who hear the name
“little tern” would probably just shrug their shoulders. The little tern
is a familiar bird to us.
Japan is an island nation, rivers flow down from the mountains to the sea
to encapsulate the beauty that is Japan. This natural beauty is an important
ecosystem. Our water rich ecosystem has supported us through farming and
fishing for centuries and the little tern has been living alongside us
for all this time.
The little tern is a migratory bird which migrates to Japan in order to
breed and raise their young. They create breeding areas called colonies
on river banks and ocean shorelines to shelter from the summer heat. Recognizable
by their small white bodies flying in large flocks and their cry “kiri-kiri”, which could be referred to as the commencement of summer. In order for
little terns to raise their young they require not only a suitable breeding
and resting area but also a successful fishing area. This requirement of
a healthy environment to flourish as a species, makes the little tern an
indicator species of a habitable waterside environment.
Every year the little tern population decreases possibly in result of a
collapsing ecosystem. One day, this once familiar species may not be so
Furthermore, it is possible that the problem also involves the fish in which little terns require to feed their young. It is difficult enough trying to catch fish underwater but the problem may be that fish shoals are declining from around breeding sites. A possible cause for environmental change is global warming. Some believe that little terns should migrate to areas with an abundant source of food. In reality suitable breeding areas and large shoals of fish coexisting are declining from all over Japan.
Lastly, landfills and similar areas were not designed for use by little
terns and though they are of use now the solution is only temporary. Also,
in natural breeding areas, little tern populations are disturbed by fishermen,
other leisurely visitors and dog walkers. If disrupted too often the little
terns will fail in breeding and ultimately not be able to repopulate in
accordance to the decline. If the decline falls below eye sight then conservation
for the species becomes more difficult. Which is why protection of the
species is most important now, before it’s too late.