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Tokyo braces for potential rat infestation after Tsukiji fish market closure

By Casey Baseel, SoraNews24

Last Saturday, the wholesale section of Tokyo’s Tsukiji fish market shut down for good, bringing an end to a 83-year seafood legacy at the site that’s earned worldwide fame. Over the weekend, merchants made the move to the brand-new Toyosu fish market, located further away from the city center, and on Thursday, the demolition of Tsukiji’s Inner Market buildings began.

But while the people and fish are now gone from Tsukiji’s Inner Market, there’s another species that experts expect is still in the building: rats. The Inner Market occupied a space roughly five times as large as Tokyo Dome, the city’s premier sports and concert venue, and once the buildings come down, the four-legged residents will be looking for new homes.

Due to the size and complex makeup of the buildings, experts say they’re unable to estimate just how many rats there are in the Inner Market. However, in preparation for the move to Toyosu, administrators began placing adhesive rat trap sheets and rat poison around the facility at the start of the year, resulting in the capture or death of some 1,700 rodents so far. With demolition work beginning, crews have set up roughly 400 capture boxes and also put up wire fences around the site, in hopes of keeping the vermin from escaping to the surrounding neighborhood. Workers are also removing power lines and overhead wiring from the Inner Market, since they’re used as walkways by the lightweight black rats that live in the buildings, as well as placing nets over water drainage openings, since the larger brown rats (which can grow up to 30 centimeters) that also live in the market are excellent swimmers.

However, experts say that even with such precautions, it will be hard to block each and every rat that’s trying to slip through the blockade. Of particular concern is the risk that rats could take up homes in the restaurants and food shops of the open-to-the-public, and still in-business, Tsukiji Outer Market.

Even a small infestation could quickly mushroom, as both black and brown rats can give birth five or six times a year, with brown rats having litters of 10 offspring and black rats five. What’s more, those rats can be ready to mate themselves in as little as three months.

So despite the efforts of the demolition crews to keep any rats from escaping, restaurants and merchants in the Outer Market are bolstering their own defenses, installing traps, placing netting or wire covers over exhaust and air vents, and replacing their existing shutters with sturdier models with smaller gaps between panels. Adhesive trap sheets have also been distributed to the residents of homes near the market, and temporary biohazard drop boxes have been set up at various points in the neighborhood where dead rats can be turned in for collection by animal control workers.

Aside from the grossness factor, experts warn that the rats are, obviously, unsanitary creatures, and their bodies should not be handled without gloves and a mask. Hygiene isn’t the only safety concern, either, as the animals’ penchants for chewing on electrical wiring raises the danger of both blackouts and fires, further adding to the list of worries for Outer Market merchants and restaurateurs who already find themselves in an unstable position with the loss of prestige for the neighborhood now that the Inner Market is gone.

Source: NHK News Web via Hachima Kiko

Read more stories from SoraNews24.

-- Tsukiji alternative – Tokyo has a second fish market, and it turns out it’s awesome too

-- Huge fire breaks out at Tokyo’s world-famous Tsukiji Fish Market【Videos, photos】

-- Tokyo’s sushi spirit shrine, where the souls of seafood slumber

© SoraNews24

©2024 GPlusMedia Inc.

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Seems like a perfect time to relocate some of Tokyo's thousands of feral cats.

11 ( +12 / -1 )

also put up wire fences around the site,....

Wonder who the idiot is that came up with this idea!

11 ( +13 / -2 )

also put up wire fences around the site,....

Wonder who the idiot is that came up with this idea!

Someone with connections to a wire-fencing contractor.

13 ( +14 / -1 )

"adhesive rat trap sheets"

And they even dare to advertise such cruelty?!

-2 ( +6 / -8 )

I have a great respect for the Governor of Tokyo, but I have a strong feeling that rats will outsmart humans.

6 ( +7 / -1 )

There's already an unexpected problem at the new location. The drains are quickly clogging up with the fish waste

5 ( +7 / -2 )

@Cricky - Hopefully they make a beeline to the diet.

Not likely. Rats are quite intelligent.

The 1,700 rats they have caught so far seems a very low number for nearly a year of trapping them. Wire fences aren’t going to do anything except create a small obstacle for the rats. Now the markets have closed down its too late to start catching them they will move onto greener pastures very quickly after their good source has run out.

6 ( +8 / -2 )

The conservative estimate is 10,000 rats 1,700 is but a drop in the ocean. I'm guessing they all are card holding members of the LDP. Some even have a blue lapel badge.

0 ( +2 / -2 )

adhesive rat trap sheets 

The cheapest and most incredibly inhumane system. Govt.-funded cruelty brought on by their own ineptitude and disorganization.

-4 ( +3 / -7 )

Agree with Jeff Huffman. Katz have always been used throughout history to control rats. It would be a good way to have a new appreciation for our feline friends instead of only the artificial, faddish obsession with cats.

0 ( +2 / -2 )

I had a chipmunk problem. Huge colony digging holes all around the yard. I'd guess 30+ individuals. New neighbors moved in with 1 cat. 8 months later, I see maybe 3 chipmonks.

Good kitty.

Now I just need a bobcat to deal with the squirrels.

2 ( +5 / -3 )


-2 ( +1 / -3 )

A bobcat? Think you might be best to adopt a Hyena. They are always laughing.

-4 ( +0 / -4 )

Reference, New Scientist, 6 October 2018, page 15

If turns out that cats are lousy at catching rats. Researchers studying a rat colony before and after feral cats moved into the zone, found that rats simply hid more. So when cats were around, the rats were less seen by people, making people prone to thinking the cats had reduced the rat population. But not so. The only cats that managed to kill rats had attacked specimens that were sick from poison.  Cats are good at killing mice but rats are too big and dangerous to be attacked.

Poisonings and traps for Tsukiji...  and for all surrounding areas where the rats will relocate.

4 ( +5 / -1 )

As I was voted down for mentioning a Hyena I now withdraw that comment and vouch instead a Sloth.

0 ( +2 / -2 )

Now I understand the job posting I saw the other day:

Position: Pied Piper

Location: Tsukiji

Employment Type: Contract employee.

Salary: Fixed salary, with lucrative incentive bonuses.

Job Requirements: Ability to communicate effectively with four legged rodents.


3 ( +3 / -0 )

So, how many cats would it take to kill and consume 10,000 rats? The thing is though, cats have too many easier food sources to bother chasing elusive rats.

A concentrsted effort of baiting and trapping would remove the rats in a few months. A pack of fox terriers running around the site could probably do it quicker. It seems as though their efforts to remove the rats are very half-assed and those contracted to do it are just drawing it out to get the cash.

0 ( +0 / -0 )

Traps and poison are the only answer. The only natural predator rats have in urban areas are humans, and we aren't so good at killing them. Local neighbourhoods are going to have to stop leaving their rubbish, in plastic bags, on the street for collection. It's like a rat restaurant.

2 ( +2 / -0 )

If sticky paper rat traps and poisons are not acceptable - as a couple of comments indicated, how about an adopt-a-rat program instead? If they are live-trapped there should be enough to go around…  :)

0 ( +2 / -2 )

Cats? Have you seen the size of some of the brown ones? A lion would be good... lock the lions there with the normal rats and the political rats that orchestrated this money waste and its a win win.

2 ( +2 / -0 )

I thought there were plans to surround the whole site with a 2m high (?) wall during demolition time, which would prevent any rodents escaping from within...

...or did I dream reading that story on here a few weeks ago?

It seems that plan has changed to ‘wire fences’ - fences (and a plan) which presumably has holes in it.

2 ( +2 / -0 )

Beauracracts can and do not make at all sense, their plans are their view of their world based in that having no real reality to base it on. It's not Suprising. 4 weeks ago this was international news, Japan really has to get with it?

1 ( +1 / -0 )

Do the Hustle is correct. Why would cats (or other predators) expend energy and risk injury chasing rats, when they could gorge themselves on the fish scraps laying around and choking the drainage system.

1 ( +1 / -0 )

So, how many cats would it take to kill and consume 10,000 rats?

The cats here don't eat what they kill. They prefer the food provided by their humans over "game."

-1 ( +0 / -1 )

Maria, I completely agree.

0 ( +0 / -0 )

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