into a predator-proof fortress. 打造成了一座抵御捕食者的堡垒

36. Now her partner brings her a beakful of mud.
    现在雄鸟衔来了泥
37. And she begins to seal herself in.
    雌鸟开始将自己封在树洞中
38. She has turned the tree hole
    雌冠斑犀鸟将树洞
39. into a predator-proof fortress.
    打造成了一座抵御捕食者的堡垒
40. But it's also...
    但同时
41. ..a prison.
    也是一座监狱
42. Her partner, however, is a regular visitor.
    伴侣雄鸟定期前往树洞

来自《行星地球 第三季 第五集 Planet Earth S03E05 森林》第 39 行