It's still there, but it takes a long time (for me) before it comes up. Or anything this morning on IS, for that matter -- painfully slow. You do have to be logged in, of course, to see it. (EDIT: Looks like the slowness may be a local problem.)
kelvinjay is correct, though, that anyone with a camera (even a camera phone) can and does shoot animals and nature. And now that IS is no longer distinguishing between cr*p and decent images, it makes it pretty much impossible for new, good images to be found.
In so many ways, it's a lost cause.