Hopefully, they take amount of plague into account. I do not know what
the plague background levels are there currently (though some Montana
locations have had enough for it to be noticed in recent years), but
it appears to be a limiting factor for colony survival when above a
certain point.

<http://www.greatfallstribune.com/article/20131106/NEWS01/311060006/Ferrets-brink-UL-Bend>

Sukie (not a vet)  Ferrets make the world a game.

Recommended ferret health links:
http://pets.groups.yahoo.com/group/ferrethealth/
http://ferrethealth.org/archive/
http://www.miamiferret.org/
http://www.ferrethealth.msu.edu/
all ferret topics:
http://listserv.ferretmailinglist.org/archives/ferret-search.html

"All hail the procrastinators for they shall rule the world tomorrow."
(2010, Steve Crandall)

A nation is as free as the least within it.

[Posted in FML 7955]