Fill in the blanks with the first letter!

Population numbers don't always go up, they sometimes go. (1) This is the story of the biological Baiji dolphin that came home to the Yangtze River.over 20,000,000 years ago, the Baekje River dolphins left the sea and swam across the Yangtze River and have been living there since.They have smaller eyes than other dolphins because the Yangtze River has many small of earth.

(2) Small scale (eyes) can help protect his eyes. (3) __________, because they have such a small environment, they cannot use their own eyes to find food. Instead, this dolphin uses echolocation to hit something back to the dolphin with sound waves showing it's in the food. This makes this dolphin unusual.

In 200 BC, there were stories told of thousands of dolphins in the Yangtze River, but today, not many people have seen dolphins.Their population has gone from a few thousand to about 150. Scientists say the number of dolphins has declined as the population living in the Yangtze River has gone up. They also say new dams are now scouring the river in search of food.

Scientists have tried different things to save this "water giant panda", but to no avail.

(4) If you had the chance to save dolphins, what would you do?