I took the picture below at Ka'ena Point, Oahu in January of 2006. In this picture, there are two Hawaiian Monk Seals. (They can be hard to spot, so I've marked the two animals in a second version of the picture below the fold.) Here's the quiz question that goes with this image: without recourse to Google, estimate the percentage of the total population of the species that can be seen in this one picture.
(Click on the pictures to view larger versions.)