But for the swiftlets living along the coasts and islands of Southeast Asia, because there are even fewer materials blown into the air from below, their job is even harder, and they must secrete even more saliva.
但散佈在東南亞群島海岸上的金絲燕，由於大海邊隨風而上的自然素材更缺乏，它們也就比其他同科的鳥兒辛苦，必須分泌更多的口水。