The city sewers have become a crocodile dungeon? They also stole the camera... Can this be considered a good thing?

In the comics, some teenage turtles live in the sewers of Manhattan, New York City. In the real world, a new study finds that the scene in the Teenage Mutant Ninja Turtles seems to have come true (even more so).

In a city in Florida, researchers found that many alligators and 35 other different animals lived in the sewers. They lived, foraged and took care of their young. Alan Ivory, the leader of the study, mentioned: "It's like a scene from "Teenage Mutant Ninja Turtles". The number of animals in the sewers is astonishing."

Urban legend comes true...

In February 2023, researchers installed 39 cameras in different locations of the sewers in Gainesville, Florida, to observe the presence of animals. According to our common sense, animals that often appear in sewers are generally rats, opossums and raccoons, but this observation shocked the researchers.

In just three months, the cameras captured 3,798 animal activities, and the variety was very rich, with a total of 35 different species. This means that the underground waterway can be called an "animal dungeon".

Crocodile is watching you｜TikTok

In the researchers' observations, raccoons appeared more than 1,000 times, bats appeared nearly 700 times, amphibians such as frogs appeared more than 100 times , and surprisingly, many reptiles were observed, including alligators 50 times, and 12 bird species . The entrances to sewers and storm drains have become the haunts of deer and bobcats.

Before this, the appearance of alligators in sewers was just an urban legend. It is said that there are many huge and ferocious alligators living in the sewers of New York City, USA. They shuttle through the sewers, eat rats, and occasionally even hurt sewer workers. Because they never see the sun, these alligators are completely white.

However, this legend has been debunked many times, because not many crocodiles have been found so far, and they usually accidentally crawl in through the drainage ditches. The manager in charge of sewers in New York City said that sewers are not suitable for crocodiles to survive. He has not seen any crocodiles in nearly 30 years of work, and it is cold in winter, so it is difficult for adult crocodiles to survive here.

The sewer alligator is an urban legend in New York City, and there are many works of art related to it. | Wiki

But in Florida, where "anything can happen", this legend has come true. Based on the data collected on alligator appearances, researchers found that these alligators appeared in some of the most "bustling" areas of the "underground city". The sewers are like their highways. If they want to go from one pond to another, they will directly "take a shortcut" underground to get there.

After all, Florida is already the next level｜Jam Press

Bats use sewers as their wintering place, using the drainage system to catch insects near manhole covers. Frogs and snakes may be accidentally washed into the sewers by a storm and live here.

Opossums and raccoons are permanent residents here. In the camera footage, researchers saw an opossum feeding its cubs, while a raccoon expertly climbed up the ladder at the manhole entrance, pulled off the camera that was magnetically attached to the manhole cover and took it away...

Researchers have found that these sewers and drains, large and small, are home to a variety of organisms | Reference 1

Why do so many animals live in sewers? Researchers mentioned that when wildlife loses a lot of living space due to urbanization and other reasons, it is not a bad thing to let them live in the rainwater drainage canals under the city.

In order to help animals, there have been special passages dug on highways for turtles and overpasses designed for red crabs. In fact, some studies have shown that it is feasible to build passages underground for wild animals.

A 2005 survey found that 374 turtle traffic incidents occurred in a year on a 1 km highway section in Florida. The survey also pointed out that in 20 years, the traffic volume on the roads in rural areas where turtles live has increased by 1-2 times, and turtles basically have difficulty surviving on the road. Data showed that when 343 turtles crossed the road, 95% were killed as soon as they stepped onto the shoulder, and the remaining 5% could not cross the first two lanes.

Because of this, some studies have found that the imbalance in the male-female ratio of American water turtles is likely because many female turtles are killed while crossing the road. This has also made many turtle species endangered, because turtles have a long maturity period, which may take more than 15 to 20 years. Traffic accidents have a serious impact on the turtle population. In 2013, a 200-year-old turtle was hit and killed on the highway.

Once a turtle steps onto the road, it is likely to encounter danger. | Reference 6

Meanwhile, it can be dangerous for humans to encounter turtles crossing the road. In 2013, a car slowed down to avoid a turtle on the road, which resulted in a three-car pileup. In some cases, drivers have gotten out of their cars to help the turtles and ended up getting hit themselves.

In 2014, the driver was killed when his vehicle flipped over after he struck a turtle.

To help turtles cross the road, it may be necessary to modify the infrastructure on the road, such as building fences and turtle-specific underpasses on the road. One survey found that after installing fences on a road, the number of turtle deaths dropped from 11.9/km/day to 0.09/km/day. Another study also found that the number of turtle and vertebrate carcasses in fenced sections decreased by 93% and 88%, respectively.

And it's not just turtles that need to cross the road. To help some animals, people around the world have built some creative animal crossing bridges. On Christmas Island in Australia, thousands of crabs cross a busy road to lay eggs in December, and a bridge built for the crabs has even become a popular tourist attraction.

A bridge built for crabs. | Reference 5

Perhaps in the future, we can really build some "underground cities" for wild animals to alleviate the negative impact of fragmented habitats on them.

Planning and production

Source: Bring Science Home (ID: steamforkids)

Author: skin

Editor: Wang Mengru

Proofread by Xu Lailinlin