sewer

The sewer alligator is an urban legend centered around alligators that live in sewers outside alligators' native range. Some cities that sewer alligators have supposedly been found are New York City and Paris. Accounts of fully grown sewer alligators are unproven, but small alligators are sometimes rescued from sewers. Stories date back to the late 1920s and early 1930s; in most instances they are part of contemporary legend.
The New York Times reports the city rescues 100 alligators per year, some directly from homes where they are kept as illegal pets (which can be legally ordered online in other states and are legal to mail when small), and some from outside (where they can attract considerable attention) though mostly above-ground. Though escapees and former pets may survive for a short time in New York sewers, longer-term survival is not possible due to the low temperatures and the bacteria in human feces. Sewer maintenance crews insist there is no underground population of alligators in sewers.

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