As their common name implies, house crows (Corvus splendens) stick pretty closely to people. So much so that there are no known populations living independently of us. You might say that, in so far as these birds have a ‘natural environment’, we’re it.
I'm not sure what this last part of the last sentence means. I'd guess the meaning was "we can't do much about it," but this is just my intuition. I've also googled up some definitions meaning "we're a team," but it doesn't seem to make sense in this context. The words are short and as common as they get, which didn't make my research attempts any easier. Any suggestions would be appreciated.