Poised on a humanmade landing platform at the entrance of a cave in northern Germany, an invasive brown rat (Rattus norvegicus) lunges at a bat and yanks it out of the air, after which it quickly becomes dinner. The discovery—documented in infrared above and reported this month in Global Ecology and Conservation—marks the first time researchers have captured rats hunting bats by grabbing them from the sky.
Scientists staked out Segeberger Kalkberg cave—about 50 kilometers north of Hamburg—between 2021 and 2024. The site is home to thousands of bats, including Natterer’s bats (Myotis nattereri) and Daubenton’s bats (M. daubentonii). The team documented 30 predation attempts and 13 kills over this period—with rats at the platform (part of a bat-counting device) either grabbing bats midflight or shortly after they landed. The behavior is all the more impressive given that the rodents hunt at night, when they are effectively blind; the rats may rely on their whiskers to detect changes in air currents caused by the bats’ flapping wings.
Given the rodents’ hunting prowess, the scientists estimate that even a small number of rats could remove thousands of bats from the cave. That makes rats a previously underappreciated decimator of these ecologically important species and a possible transmitter of bat-borne pathogens such as coronaviruses and paramyxoviruses. Scientists have previously captured video of animals eating bats in other caves—a potential route for virus transmission.
The news article is paywalled but the scientific paper is not. Link is below: the paper contains quite a few really cool videos of the rat catching a bat in mid-air, as well as discussions on conservation/biodiversity (as the rats in question are an invasive species)
Paper: https://www.sciencedirect.com/science/article/pii/S2351989425004950
First it was bat’s catching birds in mid flight, now rats are catching bats? What else will we discover related to catching and bats?
on trista cunha island, mouse grew to double the size to hunt the native albatross chicks, which decimated the population.
The videos are wild though! Never seen rats hunt. They really just sit and wait in the dark, not seeing shit, and snatch bats from the air.
Oh. My.
That video.
😳
Every time I learn a new fact about rats I get more and more alarmed
Now they have a taste for bats. Now they only eat bats.
Nice bit of work! Good that they supplied the supplemental videos, bit funny that they’re videos of videos.
An invasive rat using a man-made platform in a natural cave to decimate bat population and create a vector for disease.
It would’ve been nice if any of the humans in the article had offered potential solutions to fixing this problem we created.
Edit: I didn’t see the scientific paper linked at the bottom. Added to my reading list, hopefully there are some solutions there.
Edit 2: They’ve got some ideas:
Furthermore, straightforward infrastructure modifications can restrict rat access to bat hibernacula. For example, removing the black fabric that acted as a climbing aid at the Segeberg Kalkberg entrance eliminated predation around the light-barrier system. Additional measures – such as sealing foundation joints, blocking connections from caves to sewers and modernizing drainage systems - can prevent dispersal via sewers (Adrichem van et al., 2013). Active control should then be guided by a quantitative baseline of rat abundance: capture-mark-recapture grids, camera trap encounter rates or chew-card bite indices can clarify whether predation is driven by a few transient individuals or by a resident colony (Cavia et al., 2012, Nottingham et al., 2021, Mackenzie et al., 2022). Mechanical traps and, where legally permissible, strictly regulated rodenticides remain core tools, while integrated programs in Amsterdam and Rotterdam show that coupling waste management, public outreach, habitat modification and ongoing sewer maintenance can be highly effective (Adrichem van et al., 2013, Cock et al., 2024) Together, these measures can limit invasive-rat predation at urban hibernacula, reinforce bat-conservation objectives and reduce potential public health risks within a One-Health framework.
of all the animals rodents and bats carry the most lethal diseases: rabiesviruses, ebolavirus, and rodents hantaviruses, poxviruses.
“Let’s introduce owls. That kind of thing never causes unintended consequences!”
Realistically I don’t think they (as in the authors) as researchers can do much… but as you pointed out, there are possible ways to deal with this. Rats are common pests and I would be surprised if there aren’t some experts out there, so I am hoping that even acknowledging this issue alone would lead to better outcomes. This paper got quite a bit of traction so it definitely helps
