Why are frigatebirds called "robber birds"?

The origin of the name frigatebirds starts with their living habits. Frigatebirds have a pair of long, pointed wings and are very good at flying. When its wings are spread out, the distance between the two wingtips can reach 2.3 meters. During the day, frigatebirds are almost always soaring in the sky. They can flip and hover at high altitudes, and they can also dive in a straight line at high speeds. Their superb flying skills are truly amazing. Frigatebirds rely on this unique skill to attack other seabirds holding fish in their mouths in the air. They often rush toward their targets ferociously, causing the attackers to panic, drop the fish in their mouths, and run away in panic. At this time, the frigate bird immediately swooped down, grabbed the falling fish in its mouth, and immediately swallowed it. Because of this seabird's predatory habits, early naturalists named it frigatebird. Here, a frigate is a cannon-mounted sailing ship used by pirates in the Middle Ages. In modern English, frigate means frigate. Later, people simply called them man-of-war, which means warship. That's how the name of the frigate bird was called. Frigatebirds also obtain food by harassing other seabirds returning with prey. By disturbing other birds in flight, they often get food dropped from the mouths of other seabirds. If it sees its neighbor red-footed boobies returning from fishing, it will launch a sudden air attack on them, forcing the red-footed boobies to give up the fish and shrimp in their mouths, and then swoop down quickly to grab the fallen fish and shrimp and take them for themselves. Because of the frigate bird's "food-grabbing" behavior, people derogatorily call it "robber bird".