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QE7 t1_izxh1fd wrote

Yes, there a large differences in roost and habitat selection between species, and available habitat for maternity roosts is thought to limit the distribution of most species. Many will use trees or rocks as roosting locations in the summer. In winter some species (e.g., myotis species, tricolored bats) hibernate in caves or mines, while others migrate to Mexico or even further south (e.g., hoary bats, silver haired bats). As for human structures, big brown bats are the most commonly associated species, in fact they rarely will use natural roosts. They are commonly found in cites and urban areas, and they tend to crowd out other species by direct (i.e., echolocation jamming) or indirect competition. Little brown bats and a few other myotis species (e.g., myotis volans and myotis evotis at higher elevations) also commonly use buildings in western North America, and some speculate they may have expanded their range into prairies and very cold regions by following European settlers. Finally, tricolored bats commonly roost in culverts, while Grey bats and Mexican free tailed bats commonly use roost under bridges. Bats are amazingly diverse and complex animals.

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Gerryislandgirl t1_izxklfn wrote

“ they tend to crowd out other species by direct (i.e., echolocation jamming)”

Are you saying they jam another bat’s radar?

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QE7 t1_izxn3mq wrote

Essentially yes, although technically it’s not radar (radio waves) but sound waves. Here’s some good reading on the topic: https://www.science.org/content/article/holy-blocked-bat-signal-bats-jam-each-others-calls#:~:text=The%20jamming%20call%20works%20by,a%20process%20known%20as%20echolocation.

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lord_ne t1_izy0znl wrote

>technically it’s not radar (radio waves) but sound waves

Sonar would be a better comparison, right?

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lfrdwork t1_izyv316 wrote

I believe so, and that ships using sonar do have an effect on marine animals in the area. How much of an effect can vary, but the volume of the sonar pulse can cause direct harm.

https://www.google.com/amp/s/amp.theguardian.com/us-news/2016/jul/16/us-navy-banned-from-using-sonar-that-harms-dolphins-and-walruses

That was the first link I grabbed that discussed the fact. I'm sure there are more detailed studies that can give understanding and methods for research.

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CassandraVindicated t1_izz6pbh wrote

Modern sonar can kill marine animals with a wide area of effect. Militaries don't like to talk about it, but there's plenty of proof.

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Howtomispellnames t1_izz953z wrote

I learned this one just last week or so. Awful fact. The sonar from a navy sub can essentially liquefy you if you're close enough. Whales will swim hundreds of miles out of their way to avoid navy sonar. Sperm whale sonar is also loud enough to kill.

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CassandraVindicated t1_izzkaqt wrote

Well, at least nature did it first. I'm ex-Navy and it is an awful fact. It's not needed and isn't worth the price.

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HardlightCereal t1_izzplfp wrote

Who would have guessed that the branch of the government dedicated to killing people would kill animals too???

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CassandraVindicated t1_izzr1fw wrote

Ok, that's a fair point, but what these new sonars can do, it's like setting off a small nuke underwater. That's a little bit extreme; we wouldn't just nuke some land based target willy nilly. We shouldn't be doing it in the ocean.

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DaSaw t1_izzt6in wrote

Fortunately, I have heard that the Navy have been investigating a passive alternative. You know how someone who is intimately familiar with the sounds of a forest can detect the approach of dangerous animals (including humans) by noticing changes in the sound of animals and insects and stuff? Apparently, they're working on a system that can use marine sounds for the same purpose.

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UsedUpSunshine t1_j03rwqo wrote

I’d throw money at people for that to get done. Other night I was sitting outside enjoying nature when suddenly it got too quiet. The dogs stopped barking, the bugs went quiet. I jumped in my car real quick. Even I felt that there was something lurking. Didn’t see what it was, but I didn’t leave the car again for a while.

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HardlightCereal t1_izzrj9w wrote

https://www.forbes.com/sites/niallmccarthy/2019/06/13/report-the-u-s-military-emits-more-co2-than-many-industrialized-nations-infographic/

The consequences of climate collapse due to CO2 pollution could potentially be as damaging to the environment as a nuclear war. So yes, the military does effectively nuke land based targets willy-nilly

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CassandraVindicated t1_j0dtd85 wrote

The military (at least in the US) is not anywhere near being close to a top polluter. They led the way in remote solar and organically produced fuel. They've effectively become one of the oldest green friendly organizations.

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Unicorny_as_funk t1_j01s9tt wrote

So they’re screaming over each other to cause confusion and disorientation?

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Catfrogdog2 t1_izyl34p wrote

Also many moths have anti-bat ultrasound detection. You can demonstrate this by jingling a bunch of keys (a ready source of ultrasound) near a flying moth, and it will take evasive manoeuvres like dropping to the ground.

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[deleted] t1_izxlz3p wrote

[removed]

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jesusallin666 t1_izxhnok wrote

I live in my city's downtown and love seeing bats fly hunting in the night. Makes the mosquitoes less of an issue for me

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say592 t1_izxqgwn wrote

My understanding is bats don't actively hunt mosquitoes, as it takes more energy than they recoup. They will eat them out of opportunity, of course, but they go after slightly larger bugs.

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shapu t1_izy647n wrote

This is true for all but the smallest of bats and it's part of the reason why eradicating mosquitoes in urban areas would generally speaking cause no environmental harm.

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UEMcGill t1_izygpmm wrote

Austin Texas has a really neat history with man amd bats. Basically they encouraged bats early on by building habits (before it was cool) and now they have some amazing populations.

Its wild to watch them fly out from the Congress street bridge at dusk.

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Level9TraumaCenter t1_izxnxku wrote

Best as I know, the Indiana bat (Myotis sodalis) is rarely- if ever- found in man-made structures. Contrast with Mexican free-tails that look like they're just pouring out from the joints between bridges when they set flight in the evening.

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Stewart_Games t1_izyhiwl wrote

Northern yellow bats like to curl themselves up in Spanish moss on oak trees.

And my personal favorite are all the bats that make little tents for themselves by chewing on palm leaves to make the leaves sag into an A-frame. Like the Honduran white bat.

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AppropriateChannel39 t1_izyss4q wrote

I am just gutted that so many bat populations are being lost to white nose syndrome.

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whoary_bat t1_izzq8ki wrote

Many migratory species don’t even migrate very far south. They winter under bark and in leaf piles. Just another reason to leave your leaves.

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jordanmindyou t1_j02w2zm wrote

Everyone is always hyped about the idea of leaving leaves until I live on the property. Then all of a sudden it’s “hey u/jordanmindyou, I know you work over 60 hours a week but the lawn would look nicer if you spent your precious little free time raking it, don’t you think? I know all winter and spring and summer I said I don’t want the leaves raked this year, but now that I see that means you don’t have to rake them, I’m regretting that decision”

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gudematcha t1_j00dhqq wrote

Do bat populations always return to the same cave/place to hibernate or is that unknown?

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bullowl t1_izzsn8n wrote

Where did big brown bats roost before there were so many man-made structures?

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Stewart_Games t1_j00ccpm wrote

Besides caves they also like to use hollow logs and the old nests of pileated woodpeckers. It's actually a problem these days in some areas that a lot of species that rely on dead wood can't find big old dead trees to live inside of because humans remove dead trees from their property. You can help out by putting up bat houses.

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