Sorry I can't respond personally to those who asked about ferret-proofing
the backyard; unfortunately, I live in the state where Bob Church is going
to come and moon our esteemed Department of Fish & Game.  (Bob, hope it
works, I'm tired of being an anonymous criminal.)
 
Actually, I think ferret-proofing the backyard was easier than the house.
We have block wall fencing except where the gate is on the side of the
house.  The side of the house also has a dryer vent and a dog door into the
garage that were potential problems, so my husband built a solid, slippery
gate about four feet high that pivots up and down on hinges so that it can
be easily dropped down for ferret play time and up for when the dogs need
access to the backyard through the dog door.  He also built an enclosure
around the pool pump and equipment.
 
We then did some research to make sure that none of the plants or shrubbery
in the yard is poisonous.  We have a pool cover that locks down every two
inches into the pool deck and this cover is supposed to be strong enough to
hold an elephant.  So far we've verified it holds five bouncing ferrets, a
70-pound wanna-be ferret dog and two humans.
 
We removed anything near the block walls that could possibly be used to
climb, and I will add that out of my five little angels, I only have one
serious climber.  Every day when I walk around cleaning up after the dogs,
I walk the perimeter of the yard to make sure that no one is digging near
the fence as I realize if they put their minds to it, ferrets could dig
a hole to China.  Once we felt the yard was ferret-proofed, we closely
followed my original two boys around and let them point out any dangers
we missed.
 
I truly expected that once the novelty of the backyard wore off, they would
start trying to dig at the base of the block wall to see what's on the
other side.  Surprisingly, they prefer to dig around stepping stones,
constructing tunnels from one stone to another, especially since Rusty came
to us as I suspect he has a degree in engineering.  There is no more random
hole digging; all digging now results in intricate tunnels!  I also thought
they would try to dig where the pool cover locks down into the cement to
see if they could get under, but they seem to be distracted by the giant
ferret trampoline.
 
We installed flood lights so that the entire yard is well lit because they
don't accept the excuse that they can't play out there when it's dark.
 
I do sit out there and count heads.  I am aware that large birds have been
known to swoop down and attack.  Surprisingly, they are almost always in
sight as they run from tunnel to tunnel, to roll on the grass, to jump on
the pool cover.  I guess the different weather changes the yard from damp
to really wet to dry, etc., and they seem to find it fascinating that it's
always a little different.
 
I make sure they are all up to date on their distemper immunizations since
they spend so much time outside.  Last summer I used Advantage on them to
guard against fleas, and I'm going to talk to their vet to see what is safe
to use for heartworms in case we have mesquitos this summer.
 
Like I said in my original post, the positive behavior changes in all five
have been amazing, and I truly enjoy watching them run free.  I guess one
of the few advantages for ferrets in CA is that we tend to have block wall
fences around our back yards so they can be easily ferret-proofed.  I
realize in many parts of the country, or world for that matter, this would
be impossible.
 
I know I've probably left something out, so if you have any other
questions, please feel free to ask.
 
Posted anonymously to protect the innocent in CA
[Posted in FML issue 2970]