How about a category for "there is something there but they are too far away/"
I see animals in the distance, but to me they could be anything.
Check out the FAQ thread on "I can't tell" images and the blog post from Margaret Kosmala linked therein for a detailed explanation. Both will make you feel a lot better about guessing on indistinct shapes. A shortened version: this is a crowdsourcing project because people are better than computers at trying to figure out things like this. The more difficult the image, the larger the pool of classifications; on tough images, the correct image will usually emerge from the collection of guesses, despite the fact that some of the guesses will inevitably be wrong. Even if the mystery shapes can't be completely resolved, a collection of guesses can point to a limited number of possibilities, which still can be useful to the researchers. Certainly more useful than a bunch of "I don't know" classifications would, at any rate.
For faraway wildlife, it can help to hit CTRL+ repeatedly to enlarge the image on your monitor. Doing that for this image shows that these animals are large but don't seem to be elephants or giraffes. The coloration on at least the two on the left is a light brown to brown, so at least those two aren't buffalo or zebra. If you make the reasonable assumption that the others are the same kind of animal, they aren't buffalo or zebra, either. So, we're down to roughly a half-dozen possibilities. My completely non-expert sense is that they're too large for anything in the deer/antelope group and too tall for lions, which, if I'm classifying this one, leaves pretty much wildebeest, eland, or hartebeest. (I don't really think they're hartebeest, either, actually, based on body shape.) Even if I'm wrong and they really are, say, one of the gazelles, chances are enough other people's evaluation process will lead them to at least something in the deer/antelope group that the researchers can include this image in data sets for those animals.