Deer sure as hell know we exist.
Certain deer do, certain deer dont. Also, feel free to use a lower animal if that abstraction works better for you. My point is that if humans are some out of the way primitive life form it might make sense why aliens may know of us but not contact us (as in, there may be no purpose to explicitly contact us, as humans dont generally try to explicitly contact every deer herd).
It is not that humans are technologically primitive (which we are), it might be we are too intellectually/capacity primitive to be seen as "contact" worthy.
Maybe they have?
We don't "contact" every pack of deer that we notice.