 (1).png){kind=spacer}
2 weeks ago
13
Common rats have learned a shocking and deadly new tactic to kill other animals, which could one day lead to a deadly new pandemic among humans.
Scientists witnessed as local brown rats ambushed a colony of bats as they entered two caves in Germany, leaping into the air to catch and kill the nocturnal creatures in droves.
Moreover, these rats did this in the middle of the night and without being able to see their surroundings.
Researchers from the Leibniz Institute for Evolution and Biodiversity Science said it's the first time common rats have ever been seen in Europe acting with such predatory instincts.
Using night-vision infrared cameras, scientists watched as rats stalked the entrance of the pitch-black cave and successfully caught 13 of the 30 bats they hunted.
The study concluded that rats were now able to use their whiskers to 'feel' the bats in complete darkness, and then snatched them out of the air with their paws before surgically biting the necks to kill them.
Over the course of a full winter, the scientists estimated that just 15 rats stalking a bat cave in this manner could theoretically wipe out 2,000 to 8,000 bats, potentially causing local bat populations to collapse.
However, the threat may also extend to humans, as scientists warned that rats could begin spreading dangerous pathogens, including coronaviruses, which bats naturally carry without getting sick.
Scientists captured video evidence of rats learned how to hunt and kill flying bats in complete darkness
Although scientists warned these bat killings could, in theory, allow viruses to jump into rats and then spread more easily to people, there is no evidence this is happening yet. No immediate danger to humans has been found.
'Both bats and rats are recognized reservoirs for a wide variety of zoonotic pathogens, including coronaviruses and paramyxoviruses,' the team wrote in the journal Global Ecology and Conservation.
'These predation events provide rare evidence of direct contact between two significant wildlife reservoirs in an urban setting.'
In the US, estimates have feared there could be several million rats hiding within major cities, such as New York.
At the same time, nearly every major US city has bat populations living in diverse urban environments such as parks, bridges, buildings, and vacant lots.
Rats transmit viruses to humans primarily through direct contact with their contaminated urine, droppings, saliva, or through bites and scratches, causing people to inhale or touch infectious material in infested areas.
While fleas have acted as intermediaries for bacterial diseases like the plague, most rat-borne viruses, such as hantavirus and Lassa fever, spread directly without needing vectors such as fleas or ticks.
Bats naturally carry a wide range of viruses that can be dangerous to humans, including coronaviruses, henipaviruses that can kill up to 75 percent of infected people, the Ebola virus, and several types of rabies that are almost always fatal.
Dozens of bat corpses were discovered within cave crevices in Northern Germany, showing the rats' new hunting skills
Rats surgically stalked and then bit the necks of bats, instantly killing them, before dragging their bodies away
Researchers were stunned because no one had ever seen ordinary brown rats living in and around European cities systematically catch flying prey, and showing a level of agility that's never been associated with the pests before.
Using hidden night-vision infrared cameras and handheld thermal imagers, the team filmed rats at two huge German bat caves over several years and found clear proof of dozens of attacks plus hidden piles of half-eaten bat bodies.
Researchers at the first site, the Segeberger Kalkberg cave in Northern Germany, set up special cameras that work in total darkness and left them running continuously at the cave entrance for weeks during the fall of 2020.
After those cameras recorded crystal-clear videos of rats jumping up to grab bats in mid-air, the team discovered a hidden rat 'food stash' containing the remains of at least 52 more bats near the opening of the cave.
At the second cave, called Lüneburger Kalkberg, researchers found similar piles of half-eaten bat bodies hidden deep in rock crevices, proving the same thing was happening there, too.
In the worst-case scenario, the study warned that this new rat behavior could push some local bat populations closer to collapse, especially at big city hibernation sites that are vital for their survival.
The scientists addedthat the solution is simple: clean up food waste, use rat-proof garbage cans, seal holes that let rats reach cave entrances, and carry out careful rat control only targeting invasive brown rats, not native wildlife.
Quick, targeted action around these bat caves will protect the bats, cut any possible disease mutations between bats and rats, and keep both wildlife and people safer.
