If one nest proves susceptible to some environmental factor—be it disease, predation, or even a cold snap or wet spell—then it is likely that all the other colonies will share that vulnerability.

如果一个巢穴容易受到某些环境因素的影响——不管是疾病、掠食，亦或是寒流、潮湿期——那么极可能其他的聚居群也有着同样的弱点。