There is a chance that the rats will transfer from Tsukiji to the busy shopping streets in Ginza and elsewhere in large numbers, hiding behind shrubbery and leading off food scraps.

There are already rats swarming all over Ginza, they have been there since before the war. You'll see them hiding between the buildings, scurrying under vending machines, and running across the sidewalks at night. And if you think Ginza has a rat problem, Shibuya's is much worse.

The subway tunnels are full of rats, you can sometimes see them from the platforms.

It sounds like Mr Yabe is trying to drum up a little more business for his company.

Mr Yabe, his company and the rest of his association are obviously not very competent or the problem would not exist. Rat control is not rocket science, total extermination is probably not practical but keeping the numbers down to manageable levels is.