Construction of the new port on Ishikari Bay began in 1973. Within a decade, the development project covered about 30 percent of the area formerly occupied by the supercolony. The Japanese wood ant defends itself easily. Touch the outside of one of their mounds, and ants will rush up your arm and deliver a smarting bite. But it is extremely sensitive to change.
Vibrations caused by jackhammers and trucks can easily wipe out entire nests.
Roads, waterways and buildings can restrict the ants' ability to move between the nests of the colony. Still, the Hokkaido government and authorities in Tokyo say protecting the colony is not of particular concern. So the construction continues. Higashi rarely gets out to see his ants anymore. He has taken up studying several other types of ants and has left the research on the supercolony to his graduate students.