Bees are like condors or something, very susceptible to environmental influences. It's tremendously unfortunate (for the understatement of the century) that they are critical to a large part our food supply.
That's backwards. It's unfortunate that (apparently) our modern farming methods disrupt the natural order of things, in this case pollination.
One could say it's not a case of "fortune". It's like throwing a rock into a crowd and being surprised if someone gets hurt badly.
That is a point good enough to deserve an attempt to encapsulate it in a memorable saying. "Don't let your ecological web depend too much on indicator species" doesn't work. How about: "Don't depend on canary eggs when you live in a coal mine."