tigers will not go away

Hey folks--I must be doing something really stupid. I've tried adding header photos and the photos show up, but the 2 stock tiger images will not disappear. The new custom images I added appear on top of the tigers, which still fade back and forth to each other. I'm not providing my URL because I'm just getting started and my homepage looks ridiculous with the my images and the tigers. I love tigers but would prefer to find a different home for them. Any help? Thanks! Erin