Bats use private and social information as they hunt

While this is almost lost knowledge these days, humans and other animals have always paid attention to each other to find out what is going in on around them.

The nature (or absence of) bird or animal calls or activity can tell you that there is a large predator in the area.¹

Some animal calls are even specific to the type of threat as well.

It has even been proposed by some linguists that prairie dog calls satisfy enough of the requirements to be considered language.²

1: https://birdlanguage.com/products/what-the-robin-knows/

2: https://medium.com/health-and-biological-research-news/prair...

Somewhat off topic, semi-related, I have a bat that thinks I control the weather. If it gets too hot or cold, it will go just outside my window and squeak at me. There are patterns to it's communication, though I have no idea what exactly it is saying. I can talk to it and it talks back. Obviously we don't understand each other. I can tell it "get back to work" (taking out mosquito's) and it will leave. I think it understands tone of human voice.

When we were doing bat surveys most nights, after we caught the first few bats, we would watch later ones actively avoiding the mist nets we'd set up as the ones we caught called both from the nets and from the bags we had them in. It was also known at the time we were doing our work bats communicate feeding areas to each other and are extremely vocal in their hibernacula and roosting sites.

The bats should carry around a big banner with a warning: Are we allowed to collect information about you? :D