If PARASITIC JAEGERS are hunting in pairs they are more likely to be successful in their assaults on lesser birds than when one attacks. I have seen Terns outfly and outwit a single robber but when two villains pursue, chance of escape is slight. They take up the chase in relays exactly like a pair of Eagles after Ducks and a wise Tern or Gull yields the booty at once.
Zooms, side slips, spirals or nose dives are followed by the enemy with such rapidity as to confuse the observer's eyes. When the bit of food is small enuf to be swallowed quickly, the chase ceases abruptly — the keen-visioned pirate sees further pursuit would go unrewarded.
Northern North America. Winters south to South America and on Pacific to California.