Beaver castor
The castors and oil sacs from beavers can be valuable to the trapper
either to sell or to use for making lure. Castors and oil sacs are not
very difficult to remove from a beaver if you know where the castor is
located and how to remove them without rupturing or cutting them.
1. First, you need a beaver, as shown below. The castors and oil sacs
are located just above the vent. Note there is no external evidence of
the sex of this beaver.
2. Make a cut from the vent up the belly just under the fur about eight
inches. If you are skinning the beaver for fur, you may want to wait
until you're done skinning the beaver to remove the castors and oil
sacs. Cut shown below.
3. Peel back the fur on each side of the cut to expose the area where
the castors and oil sacs are located. The castor and oil glands are
hidden under a thin membrane of muscle - the reddish pink membrane is
clearly visible in picture #3.
4. Carefully cut through the membrane and begin peeling it away from the
castors. The castors are right below this membrane, so care must be
taken not to cut the castors. I find that if I pinch the membrane
between my index finger and thumb, I'm able to pull the membrane away
from the castor and safely cut through the membrane.
5. Once the membrane is cut away and pulled back, you can see the
castors on each side. Below the castors you can see those two pink
looking tubular shaped glands. These are the oil sacs. Also, on this
beaver you can easily see it's a male. At the upper part between the
castors, you can see the beaver's penis. A female will only have a thin
membrane at this location.
6. Next I gently grasp one castor with the fingers on one hand and with
the fingers of my other hand I pull the membrane off of the castor and
work it out. The castors need to have all the red membrane removed from
them. The castors can be very delicate and can tear easily if too much
pressure is applied. Different castors can take different amounts of
pulling before tearing. The best way to get a good at this is by doing.
7. After working both castors free of the membrane, two cuts need to be
made to free it from the beaver. The first cut is from the penis as is
shown below where the knife blade is located. Its the same on the
female, except there is only a thin membrane to cut.
8. The location of the last cut to free the castor is shown below where
the knife blade is. This cut is made where the castors are attached to
the vent. The oil glands can be easily seen above where this cut is to
be made.
9. On the tail of the beaver is the set of castors that were removed.
They are nice and full and will be partially dried and ground in
preparation for using them in making lure. Notice that there is none of
the pink membrane on the castors. It's important to make sure it is all
removed.
10. To remove the oil glands, simply cut the mebrane around them., then
cut where they join at the vent. I like to cut them so they remain with
membrane keeping them attached to one another. It is not necessary to
remove the red membrane from the oil sacs if they are to be milked of
their oil.
11. On the tail of the beaver is shown the set of castors and the oil
glands.
12. After I have the castors and oil sacs removed, I like to hang them
on the lip of a 5 gallon bucket that I keep in my truck. This begins the
drying process for the castors and oil sacs. I like to dry both the
castors and oil sacs until the outside gets a leathery feel to it. In
low humidity it takes about four or five days. I will then place the
partially dried castors in a freezer until I have accumulated enough to
make a good batch when ground. I find that the oil is easier to milk
from the oil glands after they have dried that four or five days.