Now they're everywhere feasting on all the trash and debris in Lower Manhattan.
A park cleaner in Chinatown knows all too well.
"Well I just see a lot of rats. There are a whole lot of rats here," the woman said.
The problem is so bad that city inspectors even shut down Magnolia Bakery on Bleeker Street. It's back open now.
Exterminators like Ivan Morillo have been swamped by lots of worried customers and says it's worse now than before Sandy.
"Oh yes much worse, there's definitely an increase since Sandy," said Ivan Morillo, of M and M Pest Control.
A member of one group that uses terrier dogs to hunt rats in Lower Manhattan says the problem really isn't any worse because of Sandy.
The complaints to 311, though, show a problem; On the Lower East Side in the late fall and early winter it went from 102 complaints to 123 in the same period this year. That's a 21% increase.
In Greenpoint, Brooklyn it went from 23 to 45, up 96%.
And in Carroll Gardens we saw 13 rat complaints a year ago that are up to 28 this year. That's up 115%.
That's why the city council wants to hire more inspectors and exterminators right now.
"Well it definitely seems to be worse because of Sandy. The rats were pushed inland and out of ground. But you're right, any new Yorker who takes the subway knows they're a fact of life here but it is a real public health issue," City Councilmember Jessica Lappin said.
For more information on pest control please visit: www.mandmpestcontrol.com
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