In human terms, domestic cat trilling often means saying, with a smile on your face, “Hi, nice to see you again”. Trilling is usually the sound of a friendly greeting. It would be described as a “close call vocalisation” in terms of assessing cat behaviour scientifically because it means that the vocalisation is made in close proximity to the receiver of the sound. Conversely, some domestic cat sounds like caterwauling are long-range calls. The body language which accompanies feline trilling would be the tail up position which also signals friendliness. I suppose that if you wanted to translate the tail up combined with nose touching and the trill into human behaviour it would be a handshake combined with warm words of greeting.
The cat trill is made with the mouth closed and it may merge with a meow because meowing too is part of greeting vocalisations. I’m sure that many cat owners have been met by their cat at the door with a meow and sometimes with a trill. The trill is less often heard in my opinion but the meow is always heard because it is said that the feline meow has evolved as a means to communicate with people which is why you rarely hear it in feral cat colonies.
The experts say that the domestic cat vocal repertoire includes about a dozen calls. That’s correct but there is a wide spectrum of variations of the classic meow sound and it can merge into a bark-like sound, which is a sound that my cat makes when communicating with me. Indeed, my cat both trills and meows when greeting me. He just did it about 10 minutes ago when I came in from buying the newspaper.
On a personal note, I have a neighbour’s cat who comes to see me regularly in the middle of the night. My cat has made friends with her and she only trills. I have never heard her meow or make any other sound whatsoever. Moreover, she trills all the time. She trills as she approaches my home, as she comes through the cat flap and as she walks around my home. Perhaps she has learnt that the trill is an attractive sound to humans and it may do more than simply signal friendliness. She may have learnt that the sound makes her more attractive. It’s as if she is topping up the sound, continually reinforcing the fact that she is friendly and wants me to be friendly in return.
Some experts say that mother cats trill to their offspring to get their attention. The difference between the cat meow and trill is that the meow is a learned request directed at the human caretaker normally for something such as food and attention whereas the trill is simply vocalising friendliness and is therefore a gentle request for a friendly response. It’s saying that ‘I am not hostile’.
In one respect the trill is more like a purr in terms of its production because both are made with the mouth closed. There is quite a big discussion about how the feline purr is made and you can read about this by clicking on this link if you wish. Purring is more than simply expressing contentment.
This shows a cat trilling. The sound is being made not as a greeting but as a reinforcement of friendliness.
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