Huge flock of Torresian crows

Hi everyone,

I wanted to get the opinions of those who know more about birds than me.

About a week and a half ago, a big flock of Torresian crows moved into our street (we live in Brisbane). They fly away somewhere to roost at night but come back to our area at dawn and stay in a small area around our house all day until the sun goes down. It is a large, noisy flock and they are everywhere. I have never witnessed so many crows in an area before and I'm confused about why they have suddenly come to our area and why they are in such a big flock all the time. I thought that crows lived in small groups or pairs during the day and I didn't know that they hung around in the same small area together day after day making noise constantly. They actually sit in the same tree three houses down from us during the day and fly back and forth from this tree (they don't sleep here though). They are extremley noisy to the point where I have trouble sleeping with ear plugs in and so I wanted to check whether you think this is a short term thing or whether it is likely that this strange, noisy group of crows will stay (we will sell our house and move if it is the latter). Does anyone know why they always come to our area during the day and why they stay in such a large flock all day?

Thank you,

Georgia