被捕食对象的大小，随着捕食对象（多齿蛇鲻或花斑蛇鲻）叉长的增加而增大。

In general, the size of the prey (fishes) increases with the fork length of the predator(Saurda tumbil or S. undosquamis).

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贼鸥是身手敏捷，长有叉状长尾的黑鸟。

Jaegers are swift black birds with long forked tails.

《柯林斯英汉双解大词典》

鸢鹞鹰属于鹰科的各种食肉的鸟之一，有长的，经常为叉状的尾和长而狭的翼。

Any of various predatory birds of the hawk family accipitridae having a long often forked tail and long pointed wings.

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